Question

Which of the following structures is correctly matched with its description?

• A. Septal nephridia and pharyngeal nephridia- Both are exonephric
• B. Typhlosole- Helps in grinding the soil particles and decaying leaves
• C. Sensory system- Possesses light and touch receptors in earthworm
• D. Gizzard- Internal median fold present in the dorsal wall of the intestine of earthworm

Answer 1

The correct option is C Sensory system- Possesses light and touch receptors in earthworm

• Earthworms have a simple brain that connects with nerves from their skin and muscles. The nerves detect light, vibrations and even some tastes. They do not possess eyes like humans and other complex animals; instead, they have light receptors that detect when it is light or dark. The muscles make movements in response to touch and taste.
• Septal nephridia and pharyngeal nephridia in earthworms are both enteronephric (discharging excreta into the intestine).
  
• Typhlosole in earthworms, a dorsal flap of the intestine that runs along most of its length, increases intestine surface area for more efficient absorption of digested nutrients.
  
• Gizzard, in many birds, is the hind part of the stomach, specially modified for grinding food.