Question

Spicule producing cells of sponges are
A) Spongioblasts
B) Calcoblasts
C) Silicon Blasts
D) Both A and B

Answer 1

Hint:Sponges are the members of phylum Porifera. Sponges are the multicellular organisms.The bodies of sponges are full of pores and channels that allow the water to circulate through them.

Complete Answer:
The branch of zoology that studies sponges is called Spongiology.Sponges do not have nervous, digestive or circulatory systems.They rely on constant water flow through their bodies to obtain food and oxygen and remove wastes.
Spicules of sponges:-
->Spicules are the structural elements that are present in the sponges.
->Spicules provide support to the sponges.
->Spicules provide structural support and defense against predators.

Spicules can be found in a range of symmetry types such as-
->Monaxon – Mono Axons form simple cylinders with pointed ends.
->Triaxons – Triaxons have 3 axes and each axes bears a similar ray.
->Tetraxons – Tetraxons have four axes.
->Poly Axons – Polyaxons have more than four axes.
->Dendroclones – Dendro Clones are the branching spicules arranged in irregular form or may be in a form of structures like I, Y, X shape.
Types of spicules:
Spicules are of two types-
>Megascleres – Megascleres are the large spicules that are visible to naked eyes. Their main function is to support elements in the skeleton.
>Microscleres – Microscleres are the small spicules that can not be measured by naked eyes. They are scattered throughout the tissue.
Formation of spicules:-
->The spicules are secreted by fibroblasts and as well as the Calcoblasts.
->Scleroblast are derived from the archaeocytes.

Therefore, we have seen in the above discussion that the spicule producing cells of sponges are Calcoblasts and Silicon Blasts.
Hence the correct answer is option ‘D’.

Note:The composition, size and shape of spicules are the factors that help in the determining sponges taxonomy.Spicules are the structural elements in the skeleton of sponges. In sponges, skeleton elements are formed by fibroblasts.