Question

Explain holozoic mode of nutrition in organisms.

Answer 1

Holozoic nutrition is a type of heterotrophic nutrition that involves the intake of complex organic matter, either as solids or liquids. This mode of nutrition is exhibited by a wide range of organisms from amoeba to human beings. It involves five steps namely ingestion, digestion, assimilation and egestion.
1. Ingestion: Taking in complex organic food through mouth, opening in higher animals (humans) and through body surface in lower organisms (like amoeba).
2. Digestion: Conversion of complex food into simple form, done by action of enzymes.
3. Absorption: Absorption of food in soluble form or passing of simple, soluble nutrients through blood.
4. Assimilation: Utilization of absorbed food for various metabolic processes.
5. Egestion: Expelling out the undigested food.