Correct option is B
Explanation-
A. Blastocoel → iv. Between epiblast and hypoblast
In both amphibians and avians, the blastocoel is a fluid-filled cavity. In birds, the blastocoel forms between the epiblast and hypoblast, matching option iv.
B. Blastopore lip → ii. Primitive streak
The blastopore lip in amphibians is the site of gastrulation initiation. Its avian equivalent is the primitive streak, where cells ingress to form mesoderm and endoderm.
C. Dorsal lip of blastopore → iii. Hensen’s node
The dorsal lip of the blastopore in amphibians is the organizer region, which initiates axis formation. Hensen’s node is the functional equivalent in birds — also an organizer.
D. Blastopore → v. Primitive groove
The blastopore is the opening through which cells move during gastrulation. In birds, this is functionally equivalent to the primitive groove (a groove within the primitive streak through which cells ingress).
E. Nieuwkoop center → i. Posterior Marginal Zone (PMZ)
The Nieuwkoop center in amphibians is a signaling center that induces the organizer. In birds, the Posterior Marginal Zone (PMZ) serves a similar role, initiating primitive streak formation by signaling to Koller's sickle and the epiblast.
Final Answer:
A → iv
B → ii
C → iii
D → v
E → i
Correct answer - Option b -A-iv, B-ii, C-iii, D-v, E-i
