Question

Correct sequence of events on larval development of Herdmania:
A. The blastopore of embryo closes and rudiment of tail formed
B. The chorion ruptured due to an enzyme secreted by inner follicle cells
C. The archenteron produces presumptive mesoderm as solid band
D. The presumptive notochordal occupy the central core of larva
E. The fully formed free swimming larva is produced

• A. A, C, D, B and E
• B. A, D, C, B and E
• C. B, A, C, E and D
• D. D, C, A, B and E

Hint:

Per NTA key: A, D, C, B, E; the chorion ruptures last, releasing the free-swimming larva.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:

• We must arrange the events in the larval development of the ascidian Herdmania.

Step 2: Detailed Explanation:

• As per the NTA final answer key, the sequence is: the blastopore closes and the tail rudiment forms (A), the presumptive notochordal cells occupy the central core (D), the archenteron produces the mesoderm band (C), the chorion is ruptured by the enzyme (B), and the free-swimming larva is released (E).

• The sequence is A - D - C - B - E.

Step 3: Final Answer:
The correct option is (B) A, D, C, B and E.