Module: | Embryo, Seed, Fruit & Apomixis
Q93: Consider the following statements regarding the structure and function of the epistase:
1. The epistase is a cap-like structural tissue originating from the nucellar epidermis, located at the micropylar end of the ovule.
2. It serves to provide localized mechanical protection to the delicate micropylar region of the embryo sac and often persists in the mature seed.
3. The epistase functions as an active endocrine gland, secreting massive amounts of gibberellic acid to induce natural parthenocarpy.
Which of the above statements is/are correct?
2. It serves to provide localized mechanical protection to the delicate micropylar region of the embryo sac and often persists in the mature seed.
3. The epistase functions as an active endocrine gland, secreting massive amounts of gibberellic acid to induce natural parthenocarpy.
Which of the above statements is/are correct?
✅ Correct Answer: A
The correct option is A. Statements 1 and 2 are correct, whereas Statement 3 is entirely fictional.
Just as the hypostase secures the chalazal base of the ovule, the epistase is an anatomical adaptation at the opposite pole.
In certain angiosperm families (like the Costaceae or Zingiberaceae), the nucellar epidermis situated right at the micropylar opening proliferates to form a protective, thickened tissue cap known as the epistase.
Structurally, it acts as a physical shield for the underlying egg apparatus against mechanical stress during ovule maturation and can persist into the seed stage.
Statement 3 introduces a heavy distractor.
While the epistase may have minor roles in guiding the pollen tube, it is absolutely not an endocrine gland, and it plays zero role in secreting gibberellic acid or inducing parthenocarpy (which is the development of seedless fruit).
Just as the hypostase secures the chalazal base of the ovule, the epistase is an anatomical adaptation at the opposite pole.
In certain angiosperm families (like the Costaceae or Zingiberaceae), the nucellar epidermis situated right at the micropylar opening proliferates to form a protective, thickened tissue cap known as the epistase.
Structurally, it acts as a physical shield for the underlying egg apparatus against mechanical stress during ovule maturation and can persist into the seed stage.
Statement 3 introduces a heavy distractor.
While the epistase may have minor roles in guiding the pollen tube, it is absolutely not an endocrine gland, and it plays zero role in secreting gibberellic acid or inducing parthenocarpy (which is the development of seedless fruit).