In frog, cutaneous respiration takes place

Options

A. Always
B. Only on land
C. Only in water with pulmonary respiration
D. Only in water pulmonary respiration is not occurnng

Answer

### Step-by-Step Solution:

1. **Define Cutaneous Respiration**:
- Cutaneous respiration is a mode of respiration where gas exchange occurs directly through the skin rather than through gills or lungs.

2. **Identify Organisms that Use Cutaneous Respiration**:
- This type of respiration is found in various animals including amphibians (like frogs), insects, fishes, and turtles.

3. **Understand the Frog's Life Stages**:
- Frogs exhibit different modes of respiration at different life stages. In their tadpole or larval stage, they primarily use gills (gill respiration).

4. **List the Modes of Respiration in Frogs**:
- Frogs utilize four primary modes of respiration:
- Gill respiration (in tadpoles)
- Cutaneous respiration (through the skin)
- Buccopharyngeal respiration (using the pharynx)
- Pulmonary respiration (using lungs)

5. **Explain Cutaneous Respiration in Frogs**:
- When frogs are submerged in water, they rely entirely on cutaneous respiration. Their skin is thin and permeable to water, allowing gases to diffuse easily between the blood vessels and the surrounding water.

6. **Describe the Skin Structure**:
- The skin of frogs contains a large network of blood vessels and is composed of thin membranous tissue, which facilitates the diffusion of respiratory gases.

7. **Discuss Cutaneous Respiration on Land**:
- When frogs are on land, they still utilize cutaneous respiration. The mucous glands in their skin keep it moist, which is essential for absorbing dissolved oxygen from the air.

8. **Conclude**:
- Therefore, cutaneous respiration in frogs occurs both when they are submerged in water and when they are on land, fulfilling most of their breathing needs.