From Big Medical Encyclopedia

COLOURING OF ANIMALS AND PLANTS it is caused by existence in fabrics (cells) of various pigments. Green coloring of plants is connected with presence of a chlorophyll, and yellow, red and blue coloring of flowers and fruits is caused by availability of anthocyans and carotinoids. At many animals, and in particular at all vertebrata, coloring depends on a combination of two forms of a pigment of melanin: black — eumelanine and yellow — a feomelaiina, formed of amino acids of phenylalanine and tyrosine. At disturbance of education melanin (see) arises full or partial albinism (see). The animals and plants leading a parasitic life are often deprived of pigments (helminths, parasitic plants a dodder and a broomrape).

Coloring in an animal and flora has important biol, value. At many animals coloring is one of defensors (see). Protective coloration does an animal imperceptible if its tone merges with the environment (white coloring of polar animals, grayish-yellow — desert). Coloring can have and alarm value, napr, the warning coloring inherent in poisonous or stinging animals (wasps, bees, ladybugs etc.). Raspoznavatelny coloring — the tags well visible at distance (white spots on the back at deer, antelopes, lamas etc.) — is characteristic of gregarious animals.

Bright coloring of flowers attracts the insects providing cross-pollination, coloring of fruits — facilitates their stay by the birds and animals extending seeds of fruits therefore it appears only when seeds reach a full maturity and ability to germination.

Decolourization of animals can be connected with age, a floor, influence of various external and internal factors. It is influenced by temperature, illumination, humidity and food.

See also Pigments , Pigmentation .

T. A. Zaletayeva.