Question

The cells of Porifera, which help in sexual reproduction are called as
A. Myocytes
B. Porocytes
C. Archaeocytes
D. Chromocytes

Answer 1

Hint: The body of the poriferans is composed of three layers. The middle gelatinous layer is composed of a proteinaceous matrix and different types of cells. Some of these cells are large, ameboid, and motile.

Complete answer: The phylum Porifera of the animal kingdom includes all sponges. These are asymmetrical organisms and have loosely packed cells in their body. The presence of pores in their body, a central cavity, or spongocoel and osculum is the characteristic feature of these organisms.
Their body is made up of outer and inner cell layers. A gelatin-like layer is present between these two cell layers. Myocytes are the tapering cells present near the osculum in the middle gelatinous layer. These cells are contractile and regulate the opening and closing of the aperture to control the flow of water.
Porocytes are the tube-like cells and cylindrical. These cells have a pore in the middle. The contractile nature allows them to regulate the opening of the pore. Chromocytes are the ameboid cells, rich in pigments, and have pseudopodia.
Archaeocytes are the amoeboid cells of the gelatinous layer of sponges. These cells have a large nucleus and can adopt different shapes as per the need of the organism. Archaeocytes in the sponges are involved in several functions. These cells have digestive enzymes and are involved in the digestion, the transport of the food, and excretion. These cells give rise to male or female gametes and thereby serve in sexual reproduction.
So, the correct answer is option C. Archaeocytes.

Note: Sponges reproduce both sexually and asexually. Most of the sponges are hermaphrodites and produce both eggs and sperms. Some archaeocytes of these sponges form egg cells while the other differentiates into sperms.