Question

One very special feature in the earthworm Pheretima is that

• A. The typhlosole greatly increases the effective absorption area of the digested food in the intestine.
• B. The S-shaped setae embedded in the integument are the defensive weapons used against enemies.
• C. It has a long dorsal tubular heart.
• D. Fertilization of eggs occurs inside the body.

Answer 1

The correct option is A The typhlosole greatly increases the effective absorption area of the digested food in the intestine.

The characteristic feature of the intestine between the 26-35 segment in an earthworm is the presence of internal median fold of dorsal wall called typhlosole. This increases the effective area of absorption in the intestine.