Undifferentiated totipotent cells of sponges are:

Describe reproduction in Porifera.

Assertion $(A):$ The body of sponges is supported by a skeleton.
Reason $(R):$ The skeleton of sponges is made up of spicules and spongin fibres.

Assertion $(A)$: Animals are multicellular organisms composed of eukaryotic cells.
Reason $(R)$: Sponges do not perform photosynthesis and obtain nutrition by absorption.

Collar cells occur in

The larval form found in Porifera is......