Three-Dimensional Art
A three-dimensional object is solid rather than flat, because it can be measured in three different directions, usually the height, length, and width.
Three-dimensional artifact or naturally occurring object includes man-made objects such as models, dioramas, games, puzzles, simulations, sculptures and other three-dimensional art works and their reproductions, exhibits, machines, clothing, toys, and stitchery. The category also includes such naturally occurring objects as microscope specimens (or representations of them) and other specimens mounted for viewing. This category includes archival items where the distinguishing features of the format or medium are emphasized.
Two-Dimensional Art
Two-dimensional art consists of paintings, drawings, prints, and photographs, which differ from each other primarily in the technique of their execution. Probably, our initial response to all four is a response to subject matter--that is, we first notice what the painting, drawing, print, or photograph is about. Such recognition leads us into the work's meaning and begins to shape our response to it. Beyond the recognition of subject, however, lie the technical elements chosen by artists to make their vision appear the way they wish it to appear, and these include MEDIA and COMPOSITION.
Media
The media of the two-dimensional arts are paintings, drawings, prints, and photography. Paintings and drawings can be executed with oils, watercolors, tempera, acrylics, ink, and pencils, to name a few of the more obvious. Each physical medium has its own characteristics. As an example, let us look at oils.
Composition
The second area we can isolate and respond to involves artists' use of the elements and principles of composition. These are the building blocks of two-dimensional works of art. Among others, these elements and principles include LINE, FORM, COLOR, REPETITION, and BALANCE.
Elements of Art
Seven Elements of Art:
Line:
This is a mark that is made on a surface. Lines are the first element of art and are continuous marks that are made on any surface with a moving point. A line can to used to express various things or feelings; it can be used to show various moods or anything abstract. Lines can be used in various ways to create different compositions. A horizontal or a vertical line can be used to express various things in different ways, such as, only vertical lines can be used to express an orderly feeling where are only horizontal lines can give a feeling of peace and stillness. Diagonal lines are used to create feelings of movement. It is up to the artist how he/she conveys it, in the best way possible through the use of lines. (A ship sailing a stormy sea will need diagonal lines to represent movement.)
Shape:
A shape always has two dimensions, length as well as width. This is represented as an enclosed area that is defined by color, value, space, texture and form. When lines form together, they form shapes. Shapes can be geometrical, rectangles, ovals and squares.
Form:
A form always has three dimensions; length, width and height. Examples of such would be cubes, pyramids, spheres or even cylinders. Therefore, form has depth as well as height. Sculptures and decorative arts serve as good examples for form.
Value:
The value refers to the changes in the base color. This is also determined by how much light is reflected or absorbed by any surface. Values mean the various intensities of the tones or colors. This could be the highlights, midtones or even shadows in any painting or sculpture.
Texture:
The texture is the quality of a surface or the way any work of art is represented. There are three kinds of basic textures, actual, simulated and the invented texture. Lines and shading can be used to create different textures as well. For example, if one is portraying certain fabrics, one needs to give the feeling of the right texture so that it closely resembles what the artist is trying to convey.
Color:
Color always has three characteristics, which are hue, value and the intensity. Hue means the shades (Red, yellow or pink), value refers to the lightness or the darkness and intensity refers to the brightness or dullness of the work of art.
Space:
Space is the creation of visual perspective; this gives the illusion of depth. Space can also mean the way an artist uses the area within the picture plane. Real space is actually three-dimensional. The way any artist uses the combination of positive and negative space can have a great effect on his/her entire composition. The right use of space can go a long way in creating a bigger impact with even minimum use of lines. Three-dimensional space can be created with the help of shading and perspective to give a feeling of depth.
Elements and principles of design also need to go hand in hand. Principles of design are used to organize the structural elements of design. The elements of art should be used in the right proportion to create any great work of art.
Art and Religion
By Dewitt H. Parker, Excerpted from The Principles of Aesthetics
The distinctive purpose of art, so we have argued throughout this study, is culture, the enrichment of the spirit. But lovers of art have always claimed for it more active and broader influences. To my thinking, most of such claims, especially in our age, like similar claims for religion, are greatly exaggerated. Passion, convention, economic fact in the largest sense, practical intelligence, these are the dominant forces swaying men, not beauty, not religion. Indeed, one who would compare the influence of art upon life at the present time with its influence upon primitive societies might infer the early extinction of that influence altogether. For among primitive men the influence of art is all-pervading. With them art is inseparable from utility and communal activities, upon which it has an immediate modifying or strengthening effect. The movement of civilization, with the exception of the Greek, medieval, and renaissance city states, has involved a breaking away from this original unity until, among ourselves, art is developed and enjoyed in isolation from the rest of life. Art is valued for its own sake, for its contribution to culture, not for any further influence upon life, and this freedom has come to be part of its very meaning. Instead of being interested only in pictures and statues representing ourselves, our rulers, our gods, or our neighborhood, we enjoy imitations of people who have had no effect upon our lives whatever and scenes which we have never visited, and we repair to museums to see them; instead of employing music to beautify our daily life, we leave that life for the concert hall, where we shut ourselves away for a few hours of “absolute” musical experience. Prose literature and the drama, when inspired by contemporary social problems, offer exceptions to this isolation, for through their ability to express ideas they can exert a more pervasive influence. Although social problems are solved in obedience to forces and demands beyond the control of artists, literary expression is effective in persuading and drawing into a movement men whose status would tend to make them hostile or indifferent, as in Russia, where numerous men and women of the aristocratic and wealthy classes became revolutionaries by reason of literature. And yet the literary arts also have acquired a large measure of isolation and independence. A play representing Viennese life is appreciated in New York, a novel of contemporary manners in England is enjoyed in America. Literature does not depend for its interest upon its ability to interpret and influence the life that the reader himself lives; he values it more because it extends than because it reflects that life. People decry art for art's sake, but in vain.
The development of the relation of religion to life has been parallel to the development of art. Originally, religion penetrated every activity; now, by contrast, it has been removed from one after another of the major human pursuits. Agriculture, formerly undertaken under the guidance of religion; science, once the prerogative of the priesthood; art, at one time inseparable from worship; politics, once governed by the church and pretending a divine sanction; war, until yesterday waged with the fancied cooperation of the gods—even these are now under complete secular control. To be sure, there is some music, sculpture, painting, and poetry still in the service of religion, but its relative proportion is small; kings and congresses still appeal for divine aid in times of crisis, but that is perfunctory; men still pray for rain during drought, but without faith. No one would pretend that our commerce and manufacturing have any direct relation to religion. People still invoke divine authority for moral prescriptions, but the sanctions actually operating are social instincts and fear of public opinion and the law. Religion retains a direct and potent influence only in the institution of marriage, the experience of death, philosophy, and the social life and charities conducted by the churches. Yet even in these spheres the influence is declining, and, so far as it persists, is becoming indirect. Civil and contractual marriage are slowly supplanting religious marriage; there are thousands living in our large cities who do not feel the need of the church to establish and cement their social life; most philosophers disclaim any religious motive or authority for their investigations or beliefs. Only over death does religion still hold undisputed sway.
However, despite the separation of religion and art from life, they may continue to exert influence upon it. But, barring some new integration of the sundered elements of our culture, which we may deeply desire but cannot predict, this influence must be indirect and subtle, and must occur independent of any institutional control. In the case of both it consists in imparting to life a new meaning and perfection, thus making possible a more complete affirmation of life and a freer and more genial attitude and conduct.
For unless the spirit of art or of religion is infused into life, we never find it quite satisfactory. To be sure, men sometimes think they find perfection in certain things—in practical or moral endeavor, in love or in pleasure; but unless art or religion is mixed into them, they always prove to be, in the end, disappointing. No practical purpose is ever quite successful; there is always some part of the plan left unaccomplished; and the success itself is only momentary, for time eventually engulfs it and forgets it. Practical life does not produce any permanent and complete work; its task is done only to be done over again; every house has to be repaired or torn down, every road rebuilt; every invention is displaced by a new one. This is true even on the higher planes of practical life, in political and social reconstruction. Certain evils may be removed, certain abuses remedied, but new ones always arise to take their places; and even when the entire system is remodeled and men think that the day of freedom and justice has dawned at last, they find, after a generation, a new tyranny and a new injustice. The movement of life makes it impossible for any plan to long endure. Hence the disillusion, the feeling of futility that so often poisons the triumphs of practical men. And without the spirit of art or of religion even love does not satisfy. For imagination creates the perfection of its object and, aside from institutional bonds fast loosening, a faith in the continued growth with one another and with a child, which is essentially religious, creates the permanence and meaning of its bond. Love's raptures, in so far as they are instinctive, are, of course, independent of any view of life; but apart from imagination and faith in one another, love does not keep its quality or renew itself in memory, nor can it survive death which always impends to destroy. Men often seek escape from the feeling of imperfection in frivolity, but ennui is the inevitable consequence, and reflection with its doubts cannot be stilled.
By contrast, in the religious experience and in beauty men feel that they find perfection; hence the attitude of self-surrender and joyousness characterizing both. The abandon of the spectator who decrees that for the moment his life shall be that of the work of art, is matched in the mystical experience by the emotion expressed in Dante's line, “In his will is our peace.” And in both the self-surrender is based on a felt harmony between the individual and the object—the beautiful thing appeals to the senses, its form is adapted to the structure of the mind, its content is such as to win interest and sympathy; the divine is believed to realize and quiet all of our desires. But while in beauty we feel ourselves at home with the single object, in religion we feel at rest in the universe.
When religion and art are separated from the other parts of life, as they are fast becoming now, the peculiar quality of the experiences which they offer can be rendered universal only by freely infusing it everywhere, through faith, in the case of the one, through imaginative re-creation, in the case of the other. The religious experience is a seeming revelation of a perfect meaning in life as a whole; this meaning must now be imparted to the details of life. By a free act of faith the scattered and imperfect fragments must be built into a purposive unity. The poisonous feeling of futility, will then be lost; each task, no matter how petty or ineffectual, will become momentous as contributing something toward the realization of a good beyond our little existence; and we, however lowly, will find ourselves sublime as instruments of destiny. There is nothing vain to him who believes. And if the believer cannot build a meaning into history and social life as he knows them empirically, he may extend them by faith in a future life, through which his purposes will be given the promise of eternity and the tie between parents and children, friends and lovers and co-workers, an invincible seriousness and worth. Being at peace with the universe, he may be reconciled to the accidents of his life as expressions of its Will.
The method of reconciliation through religion can well be understood by its effect on the attitude towards evil. To one who has faith in the world as perfect, evil becomes an illusion that would disappear to an adequate vision of the Divine. The supposedly evil thing becomes really a good thing—a necessary means to the fulfillment of the divine plan, either in the earthly progress of humanity or in the future life; or if the more mystical types of religion provide the starting point, where individuality itself is felt to be an illusion, a factor in the self-realization of the Absolute. The evil thing remains, of course, what it was, but the interpretation, and therefore the attitude towards it, is transformed. Pain, sorrow, and misfortune become agents for the quickening of the spirit, death a door opening to unending vistas.
The attitude of faith is not embodied in dogmatic and speculative religious doctrines alone; for it finds expression in other beliefs—in progress, in the possibility of a sunny social order, in the perpetuity of human culture, in the peculiar mission of one's race or country. Such beliefs are expressions primarily of faith, not of knowledge; like religion, they are interpretations of life based on aspiration, not on evidence; and through them men secure the same sort of re-enforcement of motive, courage, and consolation that they derive from the doctrines called religious. But the sphere of faith is wider even than this; the almost instinctive belief that each man has in his own longevity and success, the trust in the permanence of friendship and love, the confidence in the unique value of one's work or genius—these are also convictions founded more on desire than on knowledge, and may function in the same way as religion in a man's life.
The re-affirmation of life which art may inspire is independent of any belief or faith about the world. It occurs rather through the application to the objects and incidents of life of a spirit and attitude borrowed from artistic creation and appreciation. It is a generalization of the aesthetic point of view to cover life as well as art; an attempt to bring beauty from art into the whole of life. Although to-day works of art themselves are severed from direct contact with the rest of life, something of the intention and method of the artist may linger and be carried over into it. Art, the image of life, may now serve as a model, after which the latter, in its turn, will be patterned.
The spirit of art has two forms, one constructive, the other contemplative, and both may be infused into life. When the former is put there, each act and task is performed as if it were a work of art. This involves “throwing the whole self” into it, not only thought and patience, but enthusiasm and loving finish, even as the artist puts them into his work, so that it becomes a happy self-expression. Nothing shall interfere with or mar it, or spoil its value when recalled. The imperfection and transiency of the result are then forgotten in the inspiration of endeavor; and the work or act, no matter how insignificant, becomes perfect as an experience and as a memory. The generations may judge it as they will, but as an expression of the energies of my own soul, it is divine. Of course, from the industry of our time, where most work is mechanical and meaningless to him who performs it, the spirit of art has largely fled. Yet there still remain tasks which we all have to execute, if not in business, then at home, which, by arousing our interest and invention, may become materials for the spirit of art. We have at least our homes, our pleasures, our relations with one another, our private adventures, where we can still be free and genial and masterly. And for our work, art will continue to be an ideal, sorrowfully appealing.
The scope of the spirit of art may be extended beyond the single task or act to embrace the whole of one's life. Impulse offers a plastic material to which form may be given. The principles of harmony, balance, evolution, proper subordination, and perfection of detail, indispensable to beauty in art, are conditions of happiness in life. The form of a work of art and the form of a happy life are the same, as Plato insisted. In order to yield satisfaction, the different parts of life must exemplify identity of motive, continuity and orderliness in the fulfillment of purpose, lucidity of relation, yet diversity for stimulation and totality. There must be a selective scheme to absorb what is congenial and reject the unfit. This sense for form in life may lead to the same results as morality, but the point of departure and the sanction are different. Morality is largely based on conformity, on submission to the general will, and is rendered effective by fear of public disapproval and supernatural taboos; while the aesthetic direction of life has its roots in the love of form and meaning, and its sanction in personal happiness. Moreover, to the reflective person, looking before and after, life has the same sort of reality as a story, and is bound to be judged in some measure like a story. The past and the future live only in the imagination, and when we survey them there they may please us with their interest, liveliness, and meaning, much as a work of art would, or displease us with their vanity and chaos. In this way personality may acquire an imaginative value fundamentally aesthetic. This is different from moral value, which has reference to the relation of a life to social ideals; it is more comprehensive than the religious judgment, which is interested only in saving the soul; because it includes every element of life,—sense, imagination, and achievement, welcoming all, so long as they contribute something to a significant, moving whole.
The feeling for perfection of form and imaginative meaning in life is no invention of philosophers and aesthetes, but part of the normal reaction to conduct. Everybody feels that certain acts, or even certain wishes, are to be rejected by himself, not because they are intrinsically bad or wrong, but because they are inconsistent with his particular nature, and, on the other hand, that there are certain interests that should be cultivated, not because they are universally right or good, but because they are needed to give his life complete meaning. And again, all except the meanest and most repressed souls desire somewhat to shine, if not in the world at large, at least among their friends, and act with a view to appearance and to some total survey of their lives that would consider not merely its goodness or usefulness, but its imaginative emotional appeal. This appeal is the strongest on the death of a great man; this lives longest in the memory. The love of the romantic and adventurous is partly instinctive, but largely imaginative, for it has in view not merely the rapturous pleasures of the hazardous moment, but the remembered delights of recall and expression to others. The love of glory is also imaginative, a feeling for the dramatic extending even beyond the grave. The ambitious man seeks to make a story out of his life for posterity to read and remember, just as the artist makes one out of fictitious material. More might develop out of this love of form and drama in life. We have it to a certain degree of cultivation in picturesque and refined manners, dress, and ceremonial, but even there it is hampered through conventionality and want of invention; further evolved and extended into the deeper strata of life, it would lead to a more interesting and productive existence. Surely, if God is an artist as well as a judge, he will welcome into heaven not only those who have lived well, but also those who have lived beautifully.
There is no necessity, finally, why the constructive spirit of art should be confined to the personal life and should not, in some measure at least, penetrate the community and even the state. By appealing to imaginative feeling, the activities of various individuals and groups, when coordinated and given a purposeful unity, produce an aesthetic effect. The organization of a business or a university may easily come to have such a value for one who has helped to create it, especially if the place where the communal spirit operates is beautiful,—the office, the campus, the shop. Seldom, to be sure, do we find this value in our busy and haphazard America, but in many quarters the intention to create it is awake. As for the state, it is, of course, too little dominated by disinterested intelligence to be beautiful; yet Plato's ideal of statecraft as a fine art still rules the innermost dream of men.
The contemplative spirit of art is perhaps more important than the constructive in its application to life. Not that any sharp line can be drawn between them, for contemplation must always attend or follow creation, to judge and enjoy; yet towards that part of life which we cannot control, our attitude must be rather that of the spectator than the creator. We cannot interfere with the greater part of life; we can, however, observe it and, in the imagination, transform it, where we can then envisage it as we should a work of art. As we watch it, life itself may become beautiful, and instead of giving ourselves to it half-heartedly and with reserve, we shall accept it with something of the abandon of passionate love,—“In thee my soul hath her content so absolute.” To this end it is necessary to detach life from our more selfish interests and ambitions, from the habits of thought, annoying and preoccupying, that relate to self alone. To the worldly and self-centered, life is interesting only so far as it refers to pride or ambition or passion; otherwise it is indifferent, as none of their concern. But to the religious and to the aesthetically minded, there is no part of life that may not be of interest; to the former, because they impute something of transcendent perfection to it all; to the latter, because they have set themselves the inexhaustible task of its free, imaginative appreciation.
To this end, it is also necessary, after learning to view life objectively and impersonally, to attend to it leisurely and responsively, as we should to a work of art, allowing full scope to the disinterested feelings of curiosity, pity, sympathy, and wonder to create emotional participation.
Then the world may become for us the most magnificent spectacle of all. To imaginative feeling, every landscape is a potential painting, every life-story a romance, history a drama, every man or woman a statue or portrait. Beauty is everywhere, where we who are perhaps not artists but only art lovers can find it; we cannot embody it in enduring form or throw over it the glamour of sensuous loveliness, but we can perceive it with that free appreciation that is the essence of art. And for this, of course, the artists have prepared us; it is they who, by first exhibiting life as beautiful in art, have shown us that it may be beautiful as mirrored in the observing mind. One region after another has been conquered by them. The poets and the painters created the beauty of the mountains, of windmills and canals, of frozen wastes and monotonous prairies, of peasants and factories and railway stations and slums. Themselves the first to feel the value of these things, through some personal attachment or communion with them, they have made it universal through expression. Their works have become types through which we apperceive and appreciate the world: we see French landscapes as Lorrain and Corot saw them, peasants after the fashion of Millet, the stage after Degas. In vain men have prophesied limits to the victorious advance of art. Just at the time when, in the middle of the last century, some men feared that science and industry had banished beauty from the world, the impressionists and realists disclosed it in factory and steamboat and mine. In this way modern art, which might seem through its isolation to have taken beauty away from the world to itself, has given it back again.
The spirit of art, no less than of religion, can help us to triumph over the evils of life. There are three ways of treating evil successfully: the practical way, to overcome it and destroy it; the religious way, by faith to deny its existence; the aesthetic way, to rebuild it in the imagination. The first is the way of all strong men; but its scope is limited; for some of the evils of life are insuperable; against these our only recourse is faith or the spirit of art. The method of art consists in taking towards life itself the same attitude that the artist takes towards his materials when he makes a comedy or a tragedy out of them; life itself becomes the object of laughter or of tragic pity and fear and admiration. As we observed in our chapter on “The Problem of Evil in Aesthetics,” laughter is an essentially aesthetic attitude, for it implies the ability disinterestedly to face a situation, although one which opposes our standards and expectations, and to take pleasure in it. All sorts of personal feelings may be mixed with laughter, bitterness and scorn and anger; but the fact that we laugh shows that they are not dominant; in laughter we assert our freedom from the yoke of circumstance and make it yield us pleasure even when it thwarts us. Laughter celebrates a twofold victory, first over ourselves, in that we do not allow our disappointments to spoil our serenity, and second over the world, in that, even when it threatens to render us unhappy, we prevent it. Fate may rob us of everything, but not of freedom of spirit and laughter; oftentimes we must either laugh or cry, but tears bring only relief, laughter brings merriment as well.
Even with the devil laughter may effect reconciliation. Practical men will try to destroy him, but so far they have not succeeded; men of faith will prophesy his eventual ruin, but meanwhile we have to live in his company; and how can we live there at peace with ourselves unless with laughter at his antics and our own vain efforts to restrain them? Surely the age-long struggle against him justifies us in making this compromise for our happiness. We who in our lifetime cannot defeat him can at least make him yield us this bit of laughter for our pains. People who think that laughter at evil is a blasphemy against the good set too high a valuation upon their conventions. No one can laugh without possessing a standard, but to laugh is to recognize that life is of more worth than any ideal and happiness better than any morality.
And if by laughter we cannot triumph over evil, we may perhaps achieve this end by appreciating it as an element in tragedy or pathos. For once we take a contemplative attitude towards life, foregoing praise and blame, there is no spectacle equal to it for tragic pity and fear and admiration. There is a heroism in life equal to any in art, in which we may live imaginatively, and in so living forgive the evil that is its necessary condition. Or, when life is pathetic rather than tragic, suffering and fading and weak rather than strong and steady and resisting, we may win insight from the pitiable reality into the possible and ideal; the shadow of evil will suggest to us the light of the good, and for this vision we shall bless life even when it disappoints our hopes. The very precariousness of values, which is an inevitable accompaniment of them, will serve to intensify their worth for us; we shall be made the more passionately to love life, with the joys that it offers us, because we so desperately realize its transiency. Our knowledge of the inevitability of death and failure will quiet our laments, leaving us at least serene and resigned where our struggles and protests would be unavailing. It is by thus generalizing the point of view of art so that we adopt it towards our own life that we secure the catharsis of tragedy. Instead of letting sorrow overwhelm us, we may win self-possession through the struggle against it; instead of feeling that there is nothing left when the loved one dies, we may keep in memory a cherished image, more poignant and beautiful because the reality is gone, and loving this we shall love life also that has provided it.
Finally, in subtle ways, the influence of art, while remaining indirect, may affect practical action in a more concrete fashion. For silently, unobtrusively, when constantly attended to, a work of art will transform the background of values out of which action springs. The beliefs and sentiments expressed will be accepted not for the moment only, aesthetically and playfully, but for always and practically; they will become a part of our nature. The effect is not merely to enlarge the scope of our sympathies by making us responsive, as all art does, to every human aspiration, but rather to strengthen into resolves those aspirations that meet in us an answering need. This influence is especially potent during the early years of life, before the framework of valuations has become fixed. What young man nursed on Shelley's poetry has not become a lover of freedom and an active force against all oppression? But even in maturer years art may work in this way. One cannot live constantly with the “Hermes” of Praxiteles without something of its serenity entering into one's soul to purge passion of violence, or with Goethe's poetry without its wisdom making one wise to live. The effect is not to cause any particular act, but so to mold the mind that every act performed is different because of this influence.
I would compare this influence to that of friends. Friends may, of course, influence conduct directly and immediately through advice and persuasion, but that is not the most important effect of their lives. More important is the gradual diffusion of their attitudes and the enlightenment following their example. Through living their experiences with them, we come to adopt their valuations as our own; by observing how they solve their problems, we get suggestions as to how to solve ours. Art provides us with a companionship of the imagination, a new friendship. The sympathetic touch with the life there expressed enlarges our understanding of the problems and conditions of all life, and so leads to a freer and wiser direction of our own. On the one hand new and adventurous methods of living are suggested, and on the other hand the eternal limits of action are enforced.
Once more I would compare the influence of art with that of religion. The effect of religion upon conduct is partly due to the institutions with which it is connected and the supernatural sanctions which it attaches to the performance of duty; but partly also, and more enduringly, to the stories of the gods. Now these stories, even when believed, have an existence in the imagination precisely comparable to that of works of art, and their influence upon sentiment is of exactly the same order. They are most effective when beautiful, as the legends of Christ and Buddha are beautiful; and they function by the sympathetic transference of attitude from the story to the believer. Even when no longer accepted as true their influence may persist, for the values they embody lose none of their compulsion. And, although as an interpretation of life based upon faith religion is doubtless eternal, its specific forms are probably all fictitious; hence each particular religion is destined to pass from the sphere of faith to that of art. The Greek religion has long since gone there, and there also a large part of our own will some day go—what is lost for faith is retained for beauty.
Art
Art is the product or process of deliberately arranging symbolic elements in a way that influences and affects one or more of the senses, emotions, and intellect. It encompasses a diverse range of human activities, creations, and modes of expression, including music, literature, film, photography, sculpture, and paintings. The meaning of art is explored in a branch of philosophy known as aesthetics, and even disciplines such as history and psychoanalysis analyze its relationship with humans and generations.
Traditionally, the term art was used to refer to any skill or mastery. This conception changed during the Romantic period, when art came to be seen as "a special faculty of the human mind to be classified with religion and science". Generally, art is made with the intention of stimulating thoughts and emotions.
Percussion Instruments
A percussion instrument is any object which produces a sound when hit with an implement, shaken, rubbed, scraped, or by any other action which sets the object into vibration. The term usually applies to an object used in a rhythmic context or with musical intent.
The word "percussion" has evolved from Latin terms: "percussio" (which translates as "to beat, strike" in the musical sense, rather than the violent action), and "percussus" (which is a noun meaning "a beating"). As a noun in contemporary English it is described in Wiktionary as "the collision of two bodies to produce a sound". The usage of the term is not unique to music but has application in medicine and weaponry, as in percussion cap, but all known and common uses of the word, "percussion", appear to share a similar lineage beginning with the original Latin: "percussus". In a musical context then, the term "percussion instruments" may have been coined originally to describe a family of instruments including drums, rattles, metal plates, or wooden blocks which musicians would beat or strike (as in a collision) to produce sound.
History
Anthropologists and historians often speculate that percussion instruments were the first musical devices ever created. The human voice was probably the first musical instrument, but percussion instruments such as hands and feet, then sticks, rocks, and logs were almost certainly the next steps in the evolution of music.
Many caves in France, near Caberets and Grotte du Pech Merle, are believed to have been inhabited by early human communities. In those caves, anthropologists have observed red dots which appear in most places where other carvings/paintings appear. It is believed that the dots/markings were formed by people who would tap or hammer those parts of the rock which have obvious acoustic significance; tapping those particular places causes tones which resonate throughout the cavern (like the echo of voices in a giant cathedral or drums in a large hall). This may be proof that humans were aware of the acoustic properties of percussion instruments and resonating chambers as early as 25,000 years ago; though much speculation suggests that humans likely used percussion instruments long before that.
As humans developed tools for hunting and eventually agriculture, their skill and technology enabled them to craft more complex instruments. For example, a simple log may have been carved to produce louder tones (a log drum) and instruments may have been combined to produce multiple tones (as in a 'set' of log drums).
Reproductive System
Reproductive system in an organism is a collective system of many individual organs which together helps in reproduction of that particular species. Unlike other body systems, reproductive system is distinctive in its function and determines the organism’s sex. Depending on the type of organs present, reproductive systems is basically divided into male or female reproductive system.
Reproductive system is also called as Genital system. The main function of the reproductive system is to propagate particular progeny and there by to help particular species to maintain over generations. An individual organism may live healthy with out the involvement of reproductive system but it has to have functional reproductive system in order to continue its species over generations. This function of propagation of species can be achieved by several kinds of organs in several phyla or species. In vertebrates the reproductive system is well developed and may be divided into primary, secondary and accessory organs depending on their function.
Four Main Reproductive System Function
Functions of Reproductive system in vertebrates may be broadly divided into following 4 categories
Reproductive system function in producing gametes: Gametes are haploid cells produced by Gonads and carries genetic information which is further transmitted to the next generation after fertilization. In males, gametes are called sperm cells and are produced by testicles. In females, gametes are called as ova and are produced by ovaries.
Reproductive system function in transporting and maintaining viability of gametes: Gametes have to be transported from the site of their production to the site of fertilization in a viable form. In males, sperm cells are transported by vas deferens and in females by fallopian tubes.
Reproductive system function in nurturing developing offspring: Reproductive system produces certain required hormones and nutritious material to nurture growing embryo until its birth
Reproductive system function in hormone production: Reproductive system has to produce certain hormones like Luteinizing hormone, prolactin, to help the growing embryo and facilitation in child birth.
Nervous System
The nervous system is a very complex system in the body. It has many, many parts. The nervous system is separated into two main systems, the central nervous system (CNS) and the secondary nervous system. The spinal cord and the brain make up the CNS. Its main job is to get the information from the body and send out commands. The secondary nervous system is made up of all of the wiring and nerves. This system is used to send the messages from the brain to the rest of the body.
Central Nervous System: central nervous system includes brain and spinal cord. Its main function is to get the information from the body and release instructions. The brain helps to control all of the body systems and organs and spinal cord is a thick bundle of nerves, connecting our brain to the rest of the body.
The Peripheral Nervous System: it is a network of neurons that is spread throughout all the organs, muscles, and body. The neurons of CNS and PNS work together to help us think and survive. Neurons carry the messages from one neuron to another in the form of an electrical impulse. The movement of these impulses keep the body functioning.
Branches of Nervous System
Central Nervous System
The brain keeps the body in order. It helps to control all of the body systems and organs, keeping them working like they should. The brain also allows us to feel, think, remember and imagine. In general, the brain is what makes us behave as human beings.
Spinal cord and the nerves are used to make the communication between brain and rest of the boy. They tell the brain what is going on in the body at all times. This system gives instructions to all parts of the body about what to do and when to do it.
The Peripheral Nervous System:
The nervous system is made up of nerve cells or neurons that are "wired" together throughout the body, somewhat like communication system. Neurons carry messages in the form of electrical impulses. To keep the body function, the messages moves from one neuron to another.
Neuron:
A neuron is a type of cell that is found in the bodies of most animals. The features of the neuron are electrical excitability and the presence of synapses, which are complex membrane junctions used to transmit signals to other cells. The body's neurons and the glial cells that give them structural and metabolic support, together constitute the nervous system.
In vertebrates, the majority of neurons belong to central nervous system, but some reside in peripheral ganglia, and many sensory neurons are situated in sensory organs such as the retina and cochlea.
Nervous System
The nervous system is a very complex system in the body. It has many, many parts. The nervous system is separated into two main systems, the central nervous system (CNS) and the secondary nervous system. The spinal cord and the brain make up the CNS. Its main job is to get the information from the body and send out commands. The secondary nervous system is made up of all of the wiring and nerves. This system is used to send the messages from the brain to the rest of the body.
Branches of Nervous System
Central Nervous System
The brain keeps the body in order. It helps to control all of the body systems and organs, keeping them working like they should. The brain also allows us to feel, think, remember and imagine. In general, the brain is what makes us behave as human beings.
Spinal cord and the nerves are used to make the communication between brain and rest of the boy. They tell the brain what is going on in the body at all times. This system gives instructions to all parts of the body about what to do and when to do it.
The Peripheral Nervous System:
The nervous system is made up of nerve cells or neurons that are "wired" together throughout the body, somewhat like communication system. Neurons carry messages in the form of electrical impulses. To keep the body function, the messages moves from one neuron to another.
Neuron:
A neuron is a type of cell that is found in the bodies of most animals. The features of the neuron are electrical excitability and the presence of synapses, which are complex membrane junctions used to transmit signals to other cells. The body's neurons and the glial cells that give them structural and metabolic support, together constitute the nervous system.
In vertebrates, the majority of neurons belong to central nervous system, but some reside in peripheral ganglia, and many sensory neurons are situated in sensory organs such as the retina and cochlea.
Digestive System
The process of digestion is referred as mechanical and chemical breakdown of the ingested food into smaller form which can be readily and rapidly absorbed into the blood stream. The process is mainly referred as catabolism with the utilization of energy. It is also referred digestive tract and alimentary canal based on the physiological and anatomical significance.
In humans (most evolved species on earth) the digestive tract is around 5 meters – 9 meters and is composed of upper and lower digestive tract. The digestive tract is further categorized as foregut, midgut, and hindgut which speak of the embryological origin of each part.
Digestion is the process of breaking down of complex food molecules into simpler food molecules to make them absorb-able by living membranes.
The path of food through the alimentary canal is as follows:-
Mouth → Food pipe or esophagus → stomach → small intestine → large intestine → excreted
The above path can be divided into three parts:-
Digestion: complex molecules of food are broken down to simpler ones by the saliva, gastric juice, bile and pancreatic juice.
Absorption: Essential and needed components of the food are absorbed from it in the small intestine
Excretion: The waste food not containing nutrients is excreted away.
Components of Digestive System
In view of the diverse metabolic requirement of human body the digestive system is at its highest anatomical order. The flow of the food from mouth to the intestine in a proper and systematic manner is due to the proper arrangement of components in digestive system.
The digestive system is split as Upper and Lower gastrointestinal tract to understand in a better way. The upper gastrointestinal tract is composed of mouth cavity, pharynx, esophagus, stomach, and duodenum. The lower digestive tract is mainly with intestine and anus.
The lower digestive system composed of intestine is the key component in the alimentary canal and is responsible for assimilation and absorption of the food that is digested in stomach. It is also responsible for secretion of intestinal juices which are poured into stomach to enhance the digestion.
It includes the following
Small Intestine: Includes 3 parts such as Duodenum, jejunum and ileum.
Large Intestine: Also includes 3 parts: Cecum, Colon, and Rectum.
Digestive System :evolutionary Significance
In terms of evolution human digestive system stands high based on the involvement of highly developed anatomical organs as mentioned above. The human digestive system also signified the embryological development which also makes the human being as highly evolved animal on earth.
In entire animal kingdom digestive tract has a special place as it includes 4 specific organs which are under specialized category
1) Tongue: Present only in chordates.
2) Esophagus: In case of birds, insects and invertebrates it is the place of storage
3) Stomach: Birds have muscular architecture called ventriculus.
Endocrine System
The endocrine system is one of the body's control system. It consists of endocrine glands that produce chemicals called hormones, and release them into the bloodstream. The hormones act as a chemical messengers and instruct specific areas of the body to carry out certain actions. The endocrine system consists of many glands scattered throughout the body. Glands are the same in men and women except for the reproductive glands.
I.Types of Glands of Endocrine System in Human Body
Pituitary gland: The pituitary gland is present just below the brain. The pituitary gland releases at least eight hormones. Some affect body functions directly, while the remainder stimulate other endocrine glands to produce hormones of their own. The pituitary gland has two parts or lobes. The anterior lobe produces and sends hormones around the body. The posterior lobe releases hormones produced in the hypothalamus.
Hypothalamus: Hypothalamus is a part of the brain that controls the pituitary gland. It plays an important role in collecting information from other regions of the brain and blood vessels passing through it
Thyroid gland; Thyroid gland is attached to the wind pipe in our body. It makes a hormone called thyroxine. It controls body's metabolic rate.
Parathyroid gland: There are four small parathyroid glands which are embedded in the thyroid gland. It secretes hormone called parathormone. It regulates calcium levels in blood.
Thymus gland: Thymus gland lies in the lower part of the neck and upper part of the chest. Thymus gland secretes thymus hormone. It stimulates development of immune system.
II.Types of Glands of Endocrine System in Human Body
Adrenal gland: There are two adrenal glands, which are located on the top of two kidneys. The adrenal gland secretes adrenaline hormone. It helps deal with stress.
Pancreas: The pancreas is located just below the stomach in the body. Pancreas secretes the hormone called insulin. It releases hormones that control blood glucose level
Testes: Testes is present only in males. It releases male sex hormones called testosterone. Its main function is to control the development of male sex organs and male features.
Ovaries: Ovaries are present only in females. Ovaries secretes two female sex hormones called oestrogen and progesterone. Its function is to control the development of female sex organs and female features and help in pregnancy.
I.Types of Glands of Endocrine System in Human Body
Pituitary gland: The pituitary gland is present just below the brain. The pituitary gland releases at least eight hormones. Some affect body functions directly, while the remainder stimulate other endocrine glands to produce hormones of their own. The pituitary gland has two parts or lobes. The anterior lobe produces and sends hormones around the body. The posterior lobe releases hormones produced in the hypothalamus.
Hypothalamus: Hypothalamus is a part of the brain that controls the pituitary gland. It plays an important role in collecting information from other regions of the brain and blood vessels passing through it
Thyroid gland; Thyroid gland is attached to the wind pipe in our body. It makes a hormone called thyroxine. It controls body's metabolic rate.
Parathyroid gland: There are four small parathyroid glands which are embedded in the thyroid gland. It secretes hormone called parathormone. It regulates calcium levels in blood.
Thymus gland: Thymus gland lies in the lower part of the neck and upper part of the chest. Thymus gland secretes thymus hormone. It stimulates development of immune system.
II.Types of Glands of Endocrine System in Human Body
Adrenal gland: There are two adrenal glands, which are located on the top of two kidneys. The adrenal gland secretes adrenaline hormone. It helps deal with stress.
Pancreas: The pancreas is located just below the stomach in the body. Pancreas secretes the hormone called insulin. It releases hormones that control blood glucose level
Testes: Testes is present only in males. It releases male sex hormones called testosterone. Its main function is to control the development of male sex organs and male features.
Ovaries: Ovaries are present only in females. Ovaries secretes two female sex hormones called oestrogen and progesterone. Its function is to control the development of female sex organs and female features and help in pregnancy.
Muscular System
Muscular System:types of Muscles
In mammals (specifically humans) three types of muscles do exist such as skeletal muscle, cardiac (heart) muscles, and smooth muscles.
Skeletal Muscles: These are form of striated tissues, which are under the control of somatic nervous system. It is attached to the bones in the skeleton and is of voluntary in nature. The skeletal muscle contains spindle shaped cells which can fuse together to form a new cell with 2 nuclei. It is known that surprising that if this fusion continues several times it results in formation of long tubular structure called muscle fiber.
Cardiac Muscles: These constitute the involuntary muscles and appear striated which are formed by thick and thin protein filaments which are arranged alternately. It consists of specific muscle proteins called actin and myosin. The cardiac muscle cells are also known as cardiac myocytes. It is found that cardiac muscles have the power of regeneration.
Smooth Muscles: These are also involuntary and are non-striated with minimal alternate arrangement of protein filaments. These are found in arteries, veins, lymphatic vessels, urinary bladder, uterus, gastrointestinal tract, and respiratory tract.
In muscular system the muscles are classified into 3 categories. They are:
Skeletal muscles
Muscles present in heart
Smooth muscles.
The function of muscles are :
Muscles provide strength
They maintain the body balance
They contribute to the body posture
And mainly helps in movement
It also keeps body worm.
Pathology Related to Muscular System
The disorders or diseases related to muscle system can either be infectious, hormonal, genetic, autoimmune, cancerous, and even poisonous. Several disorders are found which are associated with muscular system.
Arthrogryposis
Central Core Disease
Myopathy
Laminopathy
Diastasis Recti
Zenker's Degeneration
Pelvic Floor Muscle Disorder
Orofacial Myology Disorders
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Muscular Contraction
Muscle system:
Muscle system composed of many elongated cells called muscle fibres which are able to contract and relax. Three types of muscles can be identified skeletal muscle, smooth muscle and cardiac muscle.
The sliding filament theory of muscle contraction
This model of muscular contraction was proposed independently by two research teams, that muscle contracts by the actin and myosin filaments sliding past each other. Nothing actually contracts except the length of the sacromeres and hence the whole muscle. The two research teams who proposed the hypothesis in 1954 were H.E. Huxley and J. Hanson, and A.F. Huxley and R. Niedergerke. One piece of supporting evidence regarding muscular contraction was the fact that, as muscle contracts, the dark bands (A bands) remain the same length and the light bands (I bands) and the H zones gets shorter. This is explained by the hypothesis. Evidence has now confirmed this hypothesis of muscular contraction is known as the sliding filament theory.
Muscular Contraction:filament Types
Myosin (thick filament)
A molecule of myosin consists of two distinct regions, a long rod-shaped region called a myosin rod, and a myosin head which consists of two similar globular parts. The globular heads appear at intervals along the myosin filaments, projecting from the sides of the filament. Where the actin and myosin filaments overlap, the myosin heads can attach to neighboring actin filaments. The importance of this will become clear when we deal with the actual contraction mechanism of the sacromeres.
Actin (thin filament)
Each actin filament is made up of two helical strands of globular actin molecules (G-actin) which twist round each other. The whole assembly of actin molecules is called F-actin (fibrous actin). It is thought that an ATP molecule is attached to each molecule of G-actin.
Muscular contraction mechanism
When the actin and myosin filaments overlap the myosin heads can attach like ‘hooks’ to neighboring actin filaments (f-actin), forming cross bridges. The bridges then move to pull the actin filaments past the myosin filaments and leads to muscular contraction. The energy for this movement is ATP released by the hydrolysis of enzyme ATPase to ADP and phosphate. This sequence of events is described as ratchet mechanism. The bridges form and re-form 50-100 times per second, using up ATP rapidly. This explains the need for numerous mitochondria in the muscle fibre, which can supply the ATP as a result of aerobic respiration.
Urinary System
Introduction to parts of the urinary system:
In humans, the urinary system consists of
A pair of kidneys,
One pair of ureters,
An urinary bladder
An urethra.
Urinary System Parts _kidney
Kidneys are reddish brown, bean shaped structures situated between the levels of last thoracic and third lumbar vertebra close to the dorsal inner wall ofthe abdominal cavity. Each kidney of an adult human measures 10-12 cm inlength, 5-7 cm in width, 2-3 cm in thickness with an average weight of 120-170 g. Towards the centre of the innerconcave surface of the kidney is a notch called hilum through which ureter, blood vessels and nerves enter. Inner to the hilumis a broad funnel shaped space called the renal pelvis with projections called calyces.The outer layer of kidney is a tough capsule. Inside the kidney, there are two zones, an outer cortex and an inner medulla. The medulla is divided into a few conical masses called medullary pyramids projecting into the calyces.The cortex extends in between themedullary pyramids as renal columns called Columns of Bertini .Renal artery carry impure blood for purification towards kidney and renal vein carry pure blood away from kidney.
Other Parts of Urinary System
Ureter:From the hilum of each kidney emerges a slender,whitish tube,the ureter.It is about 28cm in length.Ureter carry urine from kidney to urinary bladder
Urinary bladder:It is a median pear shaped sac situated in the pelvic region of the abdominal cavity within the front body wall.It is thick muscular,distensible lined by transitional epithelium.bladder can hold about 700-800ml of urine temporarily.
Urethra:The urethra starts from the lower part of urinary bladder and leads to the exterior.It helps in micturition.
Left suprarenal gland: cap covering the upper part of the left kidney.
Common iliac vein: vein carrying unoxygenated blood from the limbs and lower organs to the heart.
Celiac trunk: branching of the aorta feeding the abdominal viscera.
Left kidney: left blood-purifying organ.
Left renal vein: vein connecting the left kidney and the inferior vena cava.
Abdominal aorta: part of the aorta feeding the organs of the abdomen.
Erethra: small tube through which a human being expels liquid waste.
Iliac vein and artery: blood vessels in the flank region.
Ureter: tube carrying urine from the kidney to the bladder.
Renal pelvis: part of the kidney situated at the junction of the calyces and leading to the ureter.
Malpighi's pyramid: glomerules of the kidney.
Calyx: excretory cavity in the pelvis of a kidney.
Medulla: matter forming the central part of a kidney.
Cortex: matter of the cortex of the suprarenal gland.
Section of the right kidney: graphic representation of the interior of the right blood-purifying organ.
Section of the right suprarenal gland: graphic representation of the interior of the suprarenal gland.
Urinary System_structure of Nephrone
Each kidney has nearly one million complex tubular structures called nephrons, which are the functional units.Each nephron has two parts – the glomerulus and the renal tubule.Glomerulus is a tuft of capillaries formed by the afferent arteriole – a fine branch of renal artery. Blood from the glomerulus is carried away by an efferent arteriole.The renal tubule begins with a double walled cup-like structure called Bowman’scapsule, which encloses the glomerulus.Glomerulus along with Bowman’s capsule, is called the malpighian body or renal corpuscle . The tubule continues further to form a highly coiled network – proximal convoluted tubule(PCT). A hairpin shaped Henle’s loop is the next part of the tubule which has a descending and an ascending limb. The ascending limb continues as another highly coiled tubular region called distal convoluted tubule (DCT). The DCTs of many nephrons open into a straight tube called collecting duct, many of which converge and open into the renal pelvis through medullary pyramids in the calyces.The Malpighian corpuscle, PCT and DCT of the nephron are situated in the cortical region of the kidney whereas the loop of Henle dips into the medulla. In majority of nephrons, the loop of Henle is too short and extends only very little into the medulla. Such nephrons are called cortical nephrons. In some of the nephrons, the loop of Henle is very long and runs deep into the medulla.These nephrons are called juxta medullary nephrons. The efferent arteriole emerging from the glomerulus forms a fine capillary network around the renal tubule called the peritubular capillaries. A minute vessel of this network runs parallel to the Henle’sloop forming a ‘U’ shaped vasa recta. Vasa recta is absent or highly reduced in cortical nephrons
In humans, the urinary system consists of
A pair of kidneys,
One pair of ureters,
An urinary bladder
An urethra.
Urinary System Parts _kidney
Kidneys are reddish brown, bean shaped structures situated between the levels of last thoracic and third lumbar vertebra close to the dorsal inner wall ofthe abdominal cavity. Each kidney of an adult human measures 10-12 cm inlength, 5-7 cm in width, 2-3 cm in thickness with an average weight of 120-170 g. Towards the centre of the innerconcave surface of the kidney is a notch called hilum through which ureter, blood vessels and nerves enter. Inner to the hilumis a broad funnel shaped space called the renal pelvis with projections called calyces.The outer layer of kidney is a tough capsule. Inside the kidney, there are two zones, an outer cortex and an inner medulla. The medulla is divided into a few conical masses called medullary pyramids projecting into the calyces.The cortex extends in between themedullary pyramids as renal columns called Columns of Bertini .Renal artery carry impure blood for purification towards kidney and renal vein carry pure blood away from kidney.
Other Parts of Urinary System
Ureter:From the hilum of each kidney emerges a slender,whitish tube,the ureter.It is about 28cm in length.Ureter carry urine from kidney to urinary bladder
Urinary bladder:It is a median pear shaped sac situated in the pelvic region of the abdominal cavity within the front body wall.It is thick muscular,distensible lined by transitional epithelium.bladder can hold about 700-800ml of urine temporarily.
Urethra:The urethra starts from the lower part of urinary bladder and leads to the exterior.It helps in micturition.
Left suprarenal gland: cap covering the upper part of the left kidney.
Common iliac vein: vein carrying unoxygenated blood from the limbs and lower organs to the heart.
Celiac trunk: branching of the aorta feeding the abdominal viscera.
Left kidney: left blood-purifying organ.
Left renal vein: vein connecting the left kidney and the inferior vena cava.
Abdominal aorta: part of the aorta feeding the organs of the abdomen.
Erethra: small tube through which a human being expels liquid waste.
Iliac vein and artery: blood vessels in the flank region.
Ureter: tube carrying urine from the kidney to the bladder.
Renal pelvis: part of the kidney situated at the junction of the calyces and leading to the ureter.
Malpighi's pyramid: glomerules of the kidney.
Calyx: excretory cavity in the pelvis of a kidney.
Medulla: matter forming the central part of a kidney.
Cortex: matter of the cortex of the suprarenal gland.
Section of the right kidney: graphic representation of the interior of the right blood-purifying organ.
Section of the right suprarenal gland: graphic representation of the interior of the suprarenal gland.
Urinary System_structure of Nephrone
Each kidney has nearly one million complex tubular structures called nephrons, which are the functional units.Each nephron has two parts – the glomerulus and the renal tubule.Glomerulus is a tuft of capillaries formed by the afferent arteriole – a fine branch of renal artery. Blood from the glomerulus is carried away by an efferent arteriole.The renal tubule begins with a double walled cup-like structure called Bowman’scapsule, which encloses the glomerulus.Glomerulus along with Bowman’s capsule, is called the malpighian body or renal corpuscle . The tubule continues further to form a highly coiled network – proximal convoluted tubule(PCT). A hairpin shaped Henle’s loop is the next part of the tubule which has a descending and an ascending limb. The ascending limb continues as another highly coiled tubular region called distal convoluted tubule (DCT). The DCTs of many nephrons open into a straight tube called collecting duct, many of which converge and open into the renal pelvis through medullary pyramids in the calyces.The Malpighian corpuscle, PCT and DCT of the nephron are situated in the cortical region of the kidney whereas the loop of Henle dips into the medulla. In majority of nephrons, the loop of Henle is too short and extends only very little into the medulla. Such nephrons are called cortical nephrons. In some of the nephrons, the loop of Henle is very long and runs deep into the medulla.These nephrons are called juxta medullary nephrons. The efferent arteriole emerging from the glomerulus forms a fine capillary network around the renal tubule called the peritubular capillaries. A minute vessel of this network runs parallel to the Henle’sloop forming a ‘U’ shaped vasa recta. Vasa recta is absent or highly reduced in cortical nephrons
Excretory System
Introduction to Excretory system:
To survive human beings need air, food and water and removes water products from body. Carbon dioxide, urine and sweat are produced as body waste products. These need to be continuously removed from body as they are harmful. The process of removal of these products from body is called excretion.
The excretory system is a passive biological system that removes overload, unnecessary or dangerous materials from an organism, so as to help preserve homeostasis within the organism and prevent damage to the body. It is responsible for the removal of the waste products of metabolism as well as other liquid and gaseous wastes.
The major excretory organs are Skin, Lungs and the Kidneys.
Skin as Excretory System
Skin covers the whole human body and is mainly involved in protecting the human body from water loss, germs, sunlight and injury.
It acts as an excretory organ by removing sweat and excess salts from the body.
Lungs as Excretory System
Although lungs are a main component of breathing system as they help us to take in oxygen and out through trachea, bronchi and bronchial, but their significance in excretory system lies as they helps in removal of water vapours and Carbon Dioxide (from blood).
Kidney as Excretory System
Kidneys are bean shaped structures present at back of abdomen and are a part of urinary system. This system helps us to get rid of urine which is a mixture of water, salts and urea.
Urea (Product of protein degradation) is poisonous to our us and needs to be removed.
The Kidney continuously filters the blood to remove urea, excess water and salts (in form of Urine).
The urine flows through the bladder via tubes called ureters. It accumulates in bladder and is finally released when we urinate.
Woodwind instrument
A woodwind instrument is a musical instrument which produces sound when the player blows air against a sharp edge or through a reed, causing the air within its resonator (usually a column of air) to vibrate. Most of these instruments are made of wood but can be made of other materials, such as metals or plastics.
Types of woodwind instruments
Flutes
◘ Flutes produce sound when air is blown across an edge. There are two sub-families:
◘ The open flute family, in which the player's lips form a stream of air which goes directly from the players lips to the edge, such as transverse flutes and end-blown flutes. Ancient flutes were made from tubular sections of plants such as grasses, reeds, and hollowed-out tree branches. Later, flutes were made of metals such as tin, copper, or bronze. Modern concert flutes are usually made of high-grade metal alloys, usually containing nickel, silver, copper, and/or gold.
◘ The closed flute family, in which the musical instrument has a channel to form and direct the air stream over an edge. This family includes fipple-based devices such as whistles and the musical recorder family.
Reed instruments
◘ Single-reed instruments use a reed, which is a thin-cut piece of cane or plastic that is held against the aperture of a mouthpiece with a ligature. When air is forced between the reed and the mouthpiece, the reed vibrates, creating the sound. Single reed instruments include the clarinet and saxophone families, and others like the duduk and the chalumeau.
◘ Double-reed instruments, use two precisely cut, small pieces of cane joined together at the base. The finished, bound reed is inserted into the top of the instrument and vibrates as air is forced between the two pieces. There are two sub-families:
◘ Exposed double-reed instruments, where the reed goes between the player's lips. In this family include Western classical instruments the oboe, cor anglais (also called English horn) and bassoon, and many types of shawms throughout the world.
◘ Capped double-reed instruments, where the player just blows through a hole in a cap that covers the reed. This family includes the crumhorn and the cornamuse.
◘ Bagpipes can have single and/or double reeds. These are functionally the same as capped reed instruments as the reeds are not in contact with player's lips.
◘ Free reed aerophone instruments that has its sound produced as air flows past a vibrating reed in a frame. Air pressure is typically generated by breath like a harmonica or with bellows such as an accordion.
brass instrument
A brass instrument is a musical instrument whose sound is produced by sympathetic vibration of air in a tubular resonator in sympathy with the vibration of the player's lips. Brass instruments are also called labrosones, literally meaning "lip-vibrated instruments".
There are several factors involved in producing different pitches on a brass instrument: One is alteration of the player's lip tension (or "embouchure"), and another is air flow. Also, slides (or valves) are used to change the length of the tubing, thus changing the harmonic series presented by the instrument to the player.
The view of most scholars (see organology) is that the term "brass instrument" should be defined by the way the sound is made, as above, and not by whether the instrument is actually made of brass. Thus, as exceptional cases one finds brass instruments made of wood like the alphorn, the cornett, the serpent and the didgeridoo, while some woodwind instruments are made of brass, like the saxophone.
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Families of brass instruments
Modern brass instruments generally come in one of two families:
Valved brass instruments use a set of valves (typically three or four but as many as seven or more in some cases) operated by the player's fingers that introduce additional tubing, or crooks, into the instrument, changing its overall length. This family includes all of the modern brass instruments except the trombone: the trumpet, horn (also called the French horn), euphonium, and tuba, as well as the cornet, flügelhorn, tenor horn (alto horn), baritone horn, sousaphone, mellophone, and the old saxhorn. As valved instruments are predominant among the brasses today, a more thorough discussion of their workings can be found below. The valves are usually piston valves, but can be rotary valves. Rotary valves are the norm for the horn and are also prevalent on the tuba.
Slide brass instruments use a slide to change the length of tubing. The main instruments in this category are the trombone family, though valve trombones are occasionally used, especially in jazz. The trombone family's ancestor, the sackbut, and the folk instrument bazooka are also in the slide family.
There are two other families that have, in general, become functionally obsolete for practical purposes. Instruments of both types, however, are sometimes used for period-instrument performances of Baroque- or Classical-era pieces. In more modern compositions, they are occasionally used for their intonation or tone color.
Natural brass instruments, on which only notes in the instrument's harmonic series are available. Such instruments include the bugle and older variants of the trumpet and horn. The trumpet was a natural brass instrument prior to about 1795, and the horn before about 1820. In the 18th century different-length interchangeable crooks were developed which enabled a single instrument to be used for more than one key. Natural instruments are still played for period performances and some ceremonial functions, and are occasionally found in more modern scores, such as those by Richard Wagner and Richard Strauss.
Keyed or Fingered brass instruments used holes along the body of the instrument, which were covered by fingers or by finger-operated pads (keys) in a similar way to a woodwind instrument. These included the cornett, serpent, ophicleide, keyed bugle and keyed trumpet. They are more difficult to play than valved instruments.
Bore taper and diameter
Brass instruments may also be characterised by two generalizations about geometry of the bore, that is, the tubing between the mouthpiece and the flaring of the tubing into the bell. Those two generalizations are with regard to
◘ the degree of taper or conicity of the bore and
◘ the diameter of the bore with respect to its length.
Cylindricality vs. conicality
While all modern valved and slide brass instruments consist in part of conical and in part of cylindrical tubing, they are divided as follows:
◘ Cylindrical bore brass instruments are those in which approximately constant diameter tubing predominates. Cylindrical bore brass instruments are generally perceived as having a brighter, more penetrating tone quality compared to conical bore brass instruments. The trumpet, baritone horn and all trombones are cylindrical bore. In particular, the slide design of the trombone necessitates this.
◘ Conical bore brass instruments are those in which tubing of constantly increasing diameter predominates. Conical bore instruments are generally perceived as having a more mellow tone quality than the cylindrical bore brass instruments. The "British brass band" group of instruments fall into this category. This includes the flugelhorn, cornet, tenor horn (alto horn), horn, euphonium and tuba. Some conical bore brass instruments are more conical than others. For example, the flugelhorn differs from the cornet by having a higher percentage of its tubing length conical than does the cornet, in addition to possessing a wider bore than the cornet. In the 1910s and 1920s, the E.A. Couturier company built brass band instruments utilizing a patent for a continuous conical bore without cylindrical portions even for the valves or tuning slide.
Whole-tube vs. half-tube
The second division, that based on bore diameter in relation to the length determines whether it is the fundamental tone or the first overtone which is the lowest partial practically available to the player:
◘ Whole-tube instruments are ones in which the fundamental tone can be played with ease and precision. Their bore is the larger with relation to the length of the tubing. The tuba and the euphonium are instances of whole-tube brass instruments.
◘ Half-tube instruments are ones in which the fundamental tone cannot easily or accurately be played. Their bore is the smaller with relation to the length of the tubing. The second partial (first overtone) is the lowest note of each tubing length practical to play on half-tube instruments. The trumpet and horn are instances of half-tube brass instruments.
Wind instrument
A wind instrument is a musical instrument that contains some type of resonator (usually a tube), in which a column of air is set into vibration by the player blowing into (or over) a mouthpiece set at the end of the resonator. The pitch of the vibration is determined by the length of the tube and by manual modifications of the effective length of the vibrating column of air. In the case of some wind instruments, sound is produced by blowing through a reed; others require buzzing into a metal mouthpiece.
Methods for obtaining different notes
Changing the length of the vibrating air column, by changing the effective length of the tube through opening or closing holes in the side of the tube. This can be done by covering the holes with fingers or pressing a key which then closes the hole. This method is used in nearly all woodwind instruments.
◘ Changing the length of the vibrating air column, by changing the length of the tube, through engaging valves (see rotary valve, piston valve) which route the air through additional tubing, thereby increasing overall tube length, thereby lowering the fundamental pitch. This method is used on nearly all brass instruments.
◘ Changing the length of the vibrating air column, by lengthening and/or shortening the tube using a sliding mechanism. This method is used on the trombone and the slide whistle.
◘ Making the column of air vibrate at different harmonics, without changing the length of the column of air (see harmonic series).
All wind instruments use a combination of the first or second or third and the fourth method to extend their register.
Types of wind instruments
Wind instruments are typically grouped into two different families:
◘ Brass instruments
◘ Woodwind instruments
Although brass instruments were originally made of brass and woodwind instruments have traditionally been made of wood, the material used to make the body of the instrument is not always a reliable guide to its family type. A more accurate way to determine whether an instrument is brass or woodwind is to examine how the player produces sound. In brass instruments, the player's lips vibrate, causing the air within the instrument to vibrate. In woodwind instruments the player either:
◘ causes a reed to vibrate, which agitates the column of air (as in a clarinet, oboe or duduk)
◘ blows against an edge or fipple (as in a recorder), or
◘ blows across the edge of an open hole (as in a flute).
For example, the saxophone is typically made of brass, but is classified as a woodwind instrument because it produces sound with a vibrating reed.
On the other hand, the wooden cornett (not to be confused with the cornet, which is made of brass) and the serpent are both made of wood (or plastic tubing, in the case of modern serpents), but belong to the family of brass instruments because the vibrating is done by the player's lips.
In the Hornbostel-Sachs scheme of musical instrument classification, wind instruments are classed as aerophones.
Physics of Sound Production
Sound production in all wind instruments depends on the entry of air into a flow-control valve attached to a resonant chamber (resonator). The resonator is typically a long cylindrical or conical tube, open at the far end. A pulse of high pressure from the valve will travel down the tube at the speed of sound. It will be reflected from the open end as a return pulse of low pressure. Under suitable conditions, the valve will reflect the pulse back, with increased energy, until a standing wave forms in the tube.
Reed instruments such as the clarinet or oboe have a flexible reed or reeds at the mouthpiece, forming a pressure-controlled valve. An increase in pressure inside the chamber will decrease the pressure differential across the reed; the reed will open more, increasing the flow of air. The increased flow of air will increase the internal pressure further, so a pulse of high pressure arriving at the mouthpiece will reflect as a higher-pressure pulse back down the tube. Standing waves inside the tube will be odd multiples of a quarter-wavelength, with a pressure anti-node at the mouthpiece, and a pressure node at the open end. The reed vibrates at a rate determined by the resonator.
For Lip Reed (brass) instruments, the player controls the tension in their lips so that they vibrate under the influence of the air flow through them. They adjust the vibration so that the lips are most closed, and the air flow is lowest, when a low-pressure pulse arrives at the mouthpiece, to reflect a low-pressure pulse back down the tube. Standing waves inside the tube will be odd multiples of a quarter-wavelength, with a pressure anti-node at the mouthpiece, and a pressure node at the open end.
For Air Reed (flute and fipple-flute) instruments, the flow of air over the mouth of the instrument forms a flow-controlled valve. Some of the air-stream flows into the instrument's mouth, leading to an increase in internal pressure, while some of the air-stream flows across the top of the mouth--through a Bernoulli effect this reduces the pressure at the mouth, drawing air out of the mouth and leading to a decrease in internal pressure. When the pressure inside the chamber decreases, more of the air-stream will enter the mouth, and less will flow across the top of the mouth. A pulse of high pressure arriving at the mouth will direct more air across the top of the mouth; this will decrease the internal pressure, and send a low-pressure pulse back down the tube. A pulse of low pressure arriving at the mouth will draw more air into the mouth; this will increase the internal pressure, and send a high-pressure pulse back down the tube. Standing waves inside the tube will be multiples of a half-wavelength, with pressure nodes at both ends. The air-stream across the mouth vibrates at a rate determined by the resonator.
To a rough approximation, a tube of about 40 cm. will exhibit resonances near the following points:
◘ For a reed or lip-reed instrument: 220 Hz (A3), 660 Hz (E5), 1100 Hz (C#6).
◘ For an air-reed instrument: 440 Hz (A4), 880 Hz (A5), 1320 Hz (E6).
In practice, however, obtaining a range of musically useful tones from a wind instrument depends to a great extent on careful instrument design, and playing technique.
Parts
The bell of a wind instrument is the round, flared opening opposite the mouthpiece. It is found on horns, trumpets and many other kinds of instruments. On brass instruments, the acoustical coupling from the bore to the outside air occurs at the bell for all notes, and the shape of the bell optimizes this coupling. On woodwinds, most notes vent at the uppermost open tone holes; only the lowest notes of each register vent fully or partly at the bell, and the bell's function in this case is to improve the consistency in tone between these notes and the others.
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