Question

Silicoblasts occur in

• A. Calcarea
• B. Hexactinelledae
• C. Demospongia
• D. Both B and C

Answer 1

The correct option is D Both B and C

Silicoblasts are the scleroblasts that produce siliceous spicules. Scleroblasts are the cells that produce structural elements of the skeleton.

A. Class Calcarea has calcareous spicules which are made up of calcium carbonate.

B. Class Hexactinellida has siliceous spicules which are made up of silica.

C. Class Demospongiae has siliceous spicules which are made up of silica.

Since class Hexactinellida and Demospongiae have siliceous spicules, silicoblasts occur in sponges belonging to both these families.

Hence, both options B and C are correct.

So, the correct answer is 'Both B and C'.