Contractile vacuoles take part in

Options

A. Storage of wastes
B. Osmoregulation
C. Excretion
D. Both B and C

Answer

**Step-by-Step Solution:**

1. **Understanding Contractile Vacuoles:**
- Contractile vacuoles are specialized organelles found in certain protozoans. Their primary function is to manage the water content within the cell.

2. **Function of Contractile Vacuoles:**
- These vacuoles play a crucial role in osmoregulation, which is the process of maintaining the balance of water and solutes in the cell. They help to regulate the internal osmotic pressure by expelling excess water that enters the cell.

3. **Excretion Role:**
- In addition to osmoregulation, contractile vacuoles also aid in the excretion of waste products. They collect waste materials, such as ammonia, from the intracellular fluid and expel them from the cell.

4. **Evaluating the Options:**
- a. Storage of wastes: This is not a primary function of contractile vacuoles.
- b. Osmoregulation: This is a key function of contractile vacuoles.
- c. Excretion: This is also a function of contractile vacuoles.
- d. Both b and c: Since contractile vacuoles are involved in both osmoregulation and excretion, this option is correct.

5. **Conclusion:**
- The correct answer is option D, which states that contractile vacuoles take part in both osmoregulation and excretion.