Step 1 : Understanding the Question
This question requires identifying the correct statement regarding anther anatomy and pollen development. It tests knowledge about the different layers of the anther wall, the ploidy level of various tissues, and the specific functions of these components. The objective is to identify which tissue plays a vital role in providing the necessary nutrients for the transition from microspores to mature pollen grains.
Step 2 : Detailed Explanation
Pollen Wall Structure (A): A pollen grain has a two-layered wall. The "Exine" is the hard, outer layer made of sporopollenin. The "Intine" is the thin, inner layer made of cellulose and pectin. Therefore, statement (A) is incorrect as it confuses the two.
Ploidy of Sporogenous Tissue (B): The sporogenous tissue occupies the center of each microsporangium. It is part of the diploid ($2n$) sporophyte generation. These cells eventually become microspore mother cells, which then undergo meiosis to produce haploid spores. Statement (B) is incorrect.
Role of the Endothecium (C): The endothecium is a layer of the anther wall characterized by fibrous thickenings. Its primary function is to help in the dehiscence (splitting) of the anther to release pollen. It has no role in producing spores. Statement (C) is incorrect.
Function of the Tapetum (D): The tapetum is the innermost layer of the anther wall. It is characterized by dense cytoplasm and is often multinucleate. Its essential function is to provide nutrients to the developing microspores. It also produces the precursors for the sporopollenin used in the exine. Statement (D) is correct.
Step 3 : Final Answer
The only factually accurate statement in the list is that the Tapetum is responsible for nourishing the developing pollen. Thus, the correct answer is (D).