Cells of which layer of anther wall are binucleate and nourishes the developing pollen grain? (A) Epidermis (B) Exothecium (C) Middle layer (D) Tapetum

Question:

Cells of which layer of anther wall are binucleate and nourishes the developing pollen grain? 

(A) Epidermis 

(B) Exothecium 

(C) Middle layer 

(D) Tapetum

Answer: option (D) "Tapetum"

Explanation:

Structure of Microsporangium: A typical microsporangium appears nearly circular in outline. It is generally surrounded by four wall layers, viz. epidermis, endothecium, middle layers and tapetum. The outer three wall layers perform the function of protection and help in dehiscence of anther to release the pollen. Tapetum is the innermost wall layer. Tapetum nourishes the developing pollen grains. Cells of the tapetum have dense cytoplasm and are generally bi-nucleate. 

Hence, option (D) "Tapetum" is the correct answer.