Which organism group is composed of porous bodies with choanocytes and no true tissues?

Which organism group is composed of porous bodies with choanocytes and no true tissues?

• A. Polychaeta
• B. Polyp
• C. Porifera
• D. Reptilia

Answer: (C)

Sponges show a body organization built from cells rather than true tissues, and they have a porous body with a water canal system driven by choanocytes (collar cells) that capture food as water moves through. Because of this combination—porous body, choanocytes, and lack of true tissues—the group is Porifera. Other options don’t fit: polychaetes are segmented worms with true tissues and organs; a polyp is a tissue-based body form of cnidarians; reptiles are vertebrates with complex tissues and organs.

Sponges show a body organization built from cells rather than true tissues, and they have a porous body with a water canal system driven by choanocytes (collar cells) that capture food as water moves through. Because of this combination—porous body, choanocytes, and lack of true tissues—the group is Porifera. Other options don’t fit: polychaetes are segmented worms with true tissues and organs; a polyp is a tissue-based body form of cnidarians; reptiles are vertebrates with complex tissues and organs.