Write one similarity and one difference between the nutrition in amoeba and human beings.

AcademicBiologyNCERTClass 7

Similarity:

Both, the nutrition in amoeba and human beings follow the holozoic mode of nutrition. Both involve several steps of digestion such as ingestion, digestion, absorption, assimilation, and egestion.


Difference:

Amoeba is a unicellular organism therefore the complete digestion takes place in a single cell without any division of labor or the involvement of different organs.

A human being is a multicellular organism thus digestion takes place due to the involvement of various organs of the digestive system. Division of labor can be seen as different organs are involved for different steps of digestion.


Nutrition in amoeba involves the following steps:

(i) Ingestion-  Amoeba has no mouth so it ingests the food by using its pseudopodia. The food is engulfed with little water thus forming a food vacuole.
(ii) Digestion-  The food is digested by digestive enzymes present in the cytoplasm, breaking the food into small soluble molecules by chemical reactions.
(iii) Absorption- The digested food is absorbed directly into the cytoplasm by diffusion. The digested food spreads out from the food vacuole into the whole cell. The food vacuole disappears after absorption.
(iv) Assimilation- Food is used to obtain energy and the growth of the organism.
(v) Egestion- The undigested food collects inside the cell. When the cell membrane ruptures, the undigested food is thrown out of the body.

raja
Updated on 10-Oct-2022 12:46:22

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