Question

Assertion: Amoeba shows multiple fission during unfavourable conditions.
Reason: Chances of survival are less during unfavourable conditions.
A) Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
B) Both Assertion and Reason are correct, but Reason is not the correct explanation for Assertion.
C) Assertion is correct but Reason is incorrect.
D) Assertion is incorrect but Reason is correct.

Answer 1

Amoeba is a single-celled organism that performs reproduction through binary fission giving rise to two daughter cells in normal conditions. However, during unfavourable conditions for survival, it has to adopt some other method.

Complete answer: The reproduction is a biological process by which an organism produces new offsprings. There are two methods of reproduction; sexual reproduction and asexual reproduction. Sexual reproduction is a mode of reproduction in which offspring arises from two parents from the opposite sex. The generation of an offspring from a single parent is known as asexual reproduction. Two common methods of asexual reproduction are budding and binary fission. In budding, an offspring develops from an outgrowth or bud on the parent organism, e.g. yeast. In binary fission, two organisms are formed from a single parent. This mode of reproduction is usually found in unicellular organisms like Amoeba. In amoeba during unfavourable conditions, multiple fission takes place. Multiple fission is the process of producing a large number of daughter cells from one parent cell. This is done so that the chances of survival of the daughter cell in unfavourable conditions is high.
Hence, the correct answer is option A.

Note: An Amoeba has irregular body shape with pseudopodia, nucleus and other organelles. When amoeba divides to give rise to two daughter cells, nuclear division and cytoplasmic division takes place. But during unfavourable conditions, the amoeba withdraws its pseudopodia and becomes round in shape and produces a tough covering called cyst and division occurs inside it.