Question

The blind sac body plan is applicable to

• A. Porifera
• B. Annelida and Arthropoda
• C. Cnidaria and Platyhelminthes
• D. None of the above

Answer 1

Answer: (C)

Cnidaria and Platyhelminthes

The blind sac body plan is the body plan where the there is a single opening of the digestive system. The tube-like digestive system starts with a single opening through which the food is taken inside and the digested food is expelled through the same opening. The gut is lined with a single layer of endodermal cells that absorb and digest food. Cnidaria and Platyhelminthes exhibit this type of body plan.

So, the correct answer is option C.