Module: | Pollination & Outbreeding Devices
Q43: Consider the following statements regarding the structural types of the tapetum:
1. The secretory or glandular tapetum remains structurally intact in its original position while secreting nutrients directly into the sporangial locule.
2. The amoeboid or plasmodial tapetum undergoes early breakdown, with its protoplasts fusing to form a multinucleate periplasmodium that bathes the microspores.
3. To maintain genetic stability, tapetal cells of both types strictly avoid DNA replication, remaining permanently haploid throughout their lifespan.
Which of the above statements is/are correct?
2. The amoeboid or plasmodial tapetum undergoes early breakdown, with its protoplasts fusing to form a multinucleate periplasmodium that bathes the microspores.
3. To maintain genetic stability, tapetal cells of both types strictly avoid DNA replication, remaining permanently haploid throughout their lifespan.
Which of the above statements is/are correct?
✅ Correct Answer: A
The correct option is A. Statements 1 and 2 are correct, while Statement 3 is strictly incorrect.
The tapetum, the innermost nutritive layer of the anther, manifests in two primary evolutionary forms.
The secretory (glandular) type is the most common in angiosperms; its cells remain in situ and release enzymes, nutrients, and sporopollenin precursors into the locule.
The amoeboid (periplasmodial) type, found in some monocots and lower eudicots, breaks down its inner radial walls early on.
The protoplasts move into the locule and fuse, forming a giant nutrient-rich mass (periplasmodium) that directly surrounds and nourishes the developing microspores.
Statement 3 is a classical ploidy error.
Tapetal cells require massive metabolic output.
To achieve this causally, they undergo endomitosis, polyteny, or nuclear division without cytokinesis, frequently becoming distinctly polyploid or multinucleate, never remaining strictly haploid.
The tapetum, the innermost nutritive layer of the anther, manifests in two primary evolutionary forms.
The secretory (glandular) type is the most common in angiosperms; its cells remain in situ and release enzymes, nutrients, and sporopollenin precursors into the locule.
The amoeboid (periplasmodial) type, found in some monocots and lower eudicots, breaks down its inner radial walls early on.
The protoplasts move into the locule and fuse, forming a giant nutrient-rich mass (periplasmodium) that directly surrounds and nourishes the developing microspores.
Statement 3 is a classical ploidy error.
Tapetal cells require massive metabolic output.
To achieve this causally, they undergo endomitosis, polyteny, or nuclear division without cytokinesis, frequently becoming distinctly polyploid or multinucleate, never remaining strictly haploid.