Question

Excretion in amoeba occur through the
A) Lobopodia
B) Uroid portion.
C) Contractile vacuole
D) Limiting membrane

Answer 1

Hint: Amoeba is a unicellular organism found in the freshwater. In Amoeba carbon dioxide and Ammonia are the main waste material.

Complete answer:
In protozoans like Amoeba carbon dioxide and Ammonia are mostly excreted out diffusion through the general body surface. It is considered that contractile vacuoles also play some role in the removal of excretory.

Contractile vacuole absorbs excess water and waste is from a microorganism cell and excrete them into the environment by contacting. A contractile vacuole protects ourselves from absorbing too much water and potentially exploding by excreting excess water.

Wastes such as Ammonia are soluble in water they are excreted from the cell along with the excess water by contractile vacuoles. Contractile vacuole function is a periodic cycle by expanding while collecting water and contracting to release to water.

Contractile vacuole is an organelle or subcellular structure that is involved in Regulation and waste removal. The contractile vacuole acts as a protective mechanism against cellular expansion from too much water, it expels excess water from the cell by contacting. Contractile vacuole should not be confused with vacuoles which store food or water. However not all species that have contractile vacuoles are freshwater organisms, some marine and soil microorganisms also have contractile vacuole.

Therefore, the correct option is (C) Contractile vacuole.

Note: The structure of amoeba is characterised by the following features,
i) It moves with the help of pseudopodia
ii) It has cellular organelles like contractile vacuole, mitochondria, golgi apparatus, etc
iii) The cytoplasm is divided into two layers, endoplasm and ectoplasm
iv) There are 3 parts - cytoplasm, nucleus and the plasma membrane