Question

Gemmules in sponges are helpful in
A. Digestion
B. Asexual reproduction
C. Sexual reproduction
D. Conserving water

Answer 1

Hint:- Gemmule is a unique body that comprises a mass of cells which has the potential to evolve into the new organism i.e. an adult sponge. Gemmule is reluctant to desiccation i.e. drying out, freezing, along with anoxia i.e. absence of oxygen and enables sponges to withstand in severe circumstances.

Complete Answer:-
Digestion is defined as the complete breakdown of big insoluble food particles into tiny water-soluble food particles so that they can be consumed into the watery blood plasma.
Asexual reproduction involves budding, fragmentation and Gemmule. This reproduction doesn't involve the fusion of gametes. These are innermost buds form in sponges and are concerned in asexual reproduction. It is an asexually reproduced mass of cells, i.e. eligible to evolve into a new offspring. The asexual reproduction in sponges occurs by budding. These buds are maybe outer or internal. The internal buds are known as gemmules. Both species of buds evolve into new sponges i.e. capable to develop into a new organism.
Sexual reproduction involves the fusion of gametes i.e. a single pair of chromosomes combined with another to generate an individual comprise cell with 2 pairs of chromosomes. Many poriferans that reproduce by sexual mode are hermaphroditic and give eggs and sperm at different periods.

**So, the right option is Asexual reproduction i.e. option (B).
**

Note:- Gemmule denies freezing, oxygen depletion and drying. Also, if a sponge doesn’t withstand, its Gemmule performs. When conditions improve, they create another sponge which is broken off and regenerates into a new individual. The sponge is the simplest structure of animal life. Sponges can dwell for hundreds or also for thousands of years.