Question

Earthworm respires by
A.Clitellum
B.Ctenidia
C.Moist skin
D.Typhlosole

Answer 1

Hint: Earthworm is a terrestrial invertebrate which belongs to the order Opisthopora and is usually found in soil, water and moderate temperature.

Complete answer:
Earthworms do not have lungs and thus breathe through their skin. Oxygen and carbon dioxide pass through the earthworm’s skin by diffusion. Let us analyze the options to find out the correct option.

Option A: Clitellum is a thick glandular and non segmental section of earthworm body which is found near their head region. It is located at the anterior end of the body between the fourteenth and seventeenth segment and helps earthworm in copulation.Therefore, this is the incorrect option.

Option B: Ctenidia is a comblike structure which functions as a respiratory organ or a gill in molluscs and some insects.Therefore, this is the incorrect option.

Option C: Earthworms use their moist skin for respiration process through diffusion. Their skin is kept moist by the secretion of mucus and body fluid. This is the reason they are found in samp soil where moisture content is high.Therefore, this is the correct option.

Option D: Typhlosole is an internal fold in the intestine of the earthworm which forms the part of their digestive system. It helps in increasing the absorption and digestion in earthworms.Therefore, this is the incorrect option.

Hence, the correct answer is option (B)

Note: Earthworms usually come out of the soil during the night time because at night time weather is cooler and the evaporation rate is low. This helps themes in maintaining the moisture of their skin and respiration to occur.