Question

In some non chordates, during embryonic development, mesoderm occupies only a part of blastocoel adjoining ectoderm. The unoccupied portion of blastocoel persists as.

• A. Haemocoel
• B. Schizocoelic coelom
• C. Enterocoelic coelom
• D. Pseudocoelom

Hint:

Pseudocoelom is a body cavity found in some invertebrates where the cavity is not entirely lined by mesoderm, unlike in coelomates.

Answer 1

The Correct Option is D

Pseudocoelom Formation in Non-Chordates

• A: Haemocoel is a body cavity found in invertebrates, but it does not describe the unoccupied blastocoel. (❌ Incorrect)
• B: Schizocoelic coelom is formed by mesoderm splitting in some animals, not by the unoccupied blastocoel. (❌ Incorrect)
• C: Enterocoelic coelom forms from pouches of the archenteron, not from an unoccupied blastocoel. (❌ Incorrect)
• D: Pseudocoelom is the correct term, as it refers to the cavity that remains unoccupied by mesoderm in non-chordates. (✔ Correct)

Thus, the correct answer is (D).