“The process by which nutrients are acquired and utilized in the body is called nutrition.” It can also be defined as “All process involved in take in of nutrients and utilized according to the need of body is called nutrition”. This process help us in obtain energy from nutrients for growth, development, reproduction, repair of damaged body parts, to derive out metabolic process of body (etc).Organism can be divided into two mode of take in nutrients AUTOTROPHIC NUTRIENTS and HETEROTROPHIC NUTRIENTS .
LATEST METHOD OF NUTRITION IN ANIMAL:
In large animals, every cell of the body need energy yet most of the cell of body are not able to leave their position so, the mechanism is required to delivered them food. The digestive system performs this mechanism. Water, electrolyte, other nutrients are provide by digestive system. The digestive system is responsible for ingest the food, propel it and finally digest it. Undigested matter from the food is moved out of the digestive tract by the process of Egestion. On the basis of type of nutrition in animals they are classified as:
Detritivores are the animals which feed on organic debris from decomposing plant and animals. EXAMPLES earthworm is common detritivores. It take in the small pieces of organic matter mostly vegetation either at surface of soil or during burrowing.
The animals that eat plants only are called herbivores. Two important herbivores group are rodents and ungulates. In herbivores premolars and molars provide large grinding surface. They do not have canines teeth. EXAMPLES: cattle, sheep, deer, horses.
Animals that feed on other animals are called carnivores. For catching and tearing the prey, they have canine teeth and for cutting flesh, cracking bones and reducing the chunks to size suitable for swallowing, they have incisors, premolar and molars. EXAMPLES; lions, cats, bear, tigers etc.
The animals that feed on plants as well as on animals is called omnivores. They have teeth structurally and functionally intermediate between the extremes of specialization attained by the teeth of herbivores and carnivores.
EXAMPLES: human, panda, red fox, crows etc.
Most of animals feed by filter the water and take in the particles that they extract from it. EXAMPLES: Mussel (they have two gills covered with cilia), Whales etc.
When the animal feed by ingest the liquid are called fluid feeders. EXAMPLES: aphid (sucks the phloem out from the trunk of tress), mosquitoes (female mosquitoes sucks blood from skin with help of tubular mouth parts).
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