Question

When volume of the body increases due to increase in the volume of cells, not in the number of cells then it is called auxetic growth such growth is found in
A. Lizard.
B. Men.
C. Frogs.
D. Nematodes.

Answer 1

Hint: When there is an increase only in the size of the cells, but not in numbers then it is called auxetic growth. It occurs in some plant species and some animal species. In plants, auxetic growth is mainly responsible for increasing the cell size. And among animals, it occurs in some tissues, like muscles of higher animals as well as in many organisms like slender worms, tunicates, and rotifers.

Complete answer:
The auxesis comes from the Greek work “auxis” that means to “increase” or “Grow”. It is such a type of the growth in any living organism in which growth happens only in the cell size while the cell numbers in the body remain constant. So overall, the volume and the density of the body increases and size of the cell numbers in the body remains the same as it was at the time of birth of that organism. The cell grows by the process of enlargement.
Auxetic growth is present in nematodes, plankton feeder’s tunicates, and aquatic marine animals of phylum rotifers.
Option A, B and C all are incorrect because the lizards, men and frogs all show the cell division in their life cycle. Both the cell division and cell growth occurs in them simultaneously during the growth period in their life span. This type of growth is known as multiplication growth.

Hence, the correct answer is option (D).

Note: Cell proliferation: growth of the body by cell multiplication and division.
 Cell enlargement: growth occurs in the body but cell division does not happen and cell density only increases by the synthesis of cytoplasm.
Cell acceleration: growth occurs in the body due to secretion of a large amount of extracellular material.