Question

What is true of wall of pollen sac?

• A. Endothecium occurs inner to tapetum
• B. Tapetum lies below the endothecium
• C. Middle layers occur below the epidermis and outside the tapetum
• D. Middle layers lie between endothecium and tapetum

Answer 1

The correct option is D Middle layers lie between endothecium and tapetum

The wall of pollen sac comprises of four layers: Epidermis, Endothecium, Middle layers and Tapetum. Epidermis is followed by a single layer of Endothecium, 2-3 middle layers and a single layer of Tapetum. Tapetum is the innermost layer of the pollen sac.Tapetum surrounds the sporogenous tissue completely.

Hence, the order of layers from outside to inside is:

Epidermis, Endothecium, Middle layers and Tapetum.

Therefore, middle layers lie between the endothecium and the tapetum.

So, the correct answer is D.