Monday, November 11, 2019

Locomotion and Movements

Locomotion Is one of the Important characteristics of all living beings as plants and animals. Mostly plants are fixed but some plants move. Plants are fixed but even then they show movements as leaves of plants, touch-me-not show remarkable movements, when touched by hand. The sunflower bends towards the sunlight. During the night time so many plants fold their leaves or close the petals but next morning the leaves and petals are opened normally. Plants like chlamydeous and Volvo changes their places.Animals move from here from there in search of food ND shelter. Animals also move from place to place to avoid unfavorable conditions, for mating. To lay eggs, to make their nests (birds). Animals also run very fast to save themselves from predators. Some animals like coral, sponge and sea-anemone do not change their places. Movements mean change the position of body parts in the relation body axis but whole body does not move. For example when limbs are moved, fingers are moved to hold the things. Neck is moved towards the sides to look and tall Is moved for different purposes.Locomotion means the position of entire odd Is changed from one place to another, this takes place due to some reasons such as to obtain food, to get shelter and avoid enemies. Grazing animals, like cow, horse, goat move from place to place, birds fly away, when they are going to be caught, frog jumps into the water when it feels danger. MOVEMENTS IN ANIMALS There are so many types of animals such as unicellular, small, medium size and very large size animals all show movements either they are aquatic, arboreal or terrestrial.Microscopic animals such as Amoeba, Paramecium and euglena show following types f movements. (A) Amoeba: Amoeba is found In water. It shows creeping movements. Locomotors movements of amoeba are brought by the formation of finger like projections called pseudopodia (false feet). Several pseudopodia may project out at in any time but one pseudopodia may be continuously projecting in a specific direction, this is called leading pseudopodia, remaining Pseudopodia are withdrawn and amoeba moves in desired direction, this type of movements also occurs in W. B. C of human blood. B) Euglena: Euglena shows flagella movement . Euglena moves tit the help of thread like structure called flagellum. Flagellum extends out through the front end of Euglena, during the movements, the flagellum beats back and forth to draw the Euglena forward in the in water with a spiral rotation on straight line (swimming movements). (C) Paramecium: The whole body is recovered by thread like cilia which help paramecium in movement, this movements is called cilia movements. The cilia beat the water backwards and the paramecium moves forward, and as their stroke Is oblique, It rotates on Its longitudinal axis.When calla beat award direction the paramecium moves backwards (swimming movements). (D) Hydra: Hydra is a fixed aquatic organism. It shows two types of bending movements- 1. Looping : Hydra moves with the help of its tentacles. Hydra bends its body and fixes the tentacles on the ground, now it frees its fixed end and draws it near the tentacles and now the body becomes straight up again. 2. Somersaulting : In this releases its base and make the body straight and upside down and again bends the body forward till it touches the ground and now it releases the tentacles to make the body straight. INSECTSSome insects lack wings and they are unable to fly like silverfish and head lice. Some insects like housefly and mosquito have one pair of wing, which are called fore wings, they fly with the help of these wings. Some insects have two pairs of wings the fore and hind wings, like butterfly and dragonfly.

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