Mammals can regenerate

Options

A. Brain
B. Liver
C. Lung
D. Urinary bladder

Answer

**Step-by-Step Solution:**

1. **Understanding Regeneration**: Regeneration refers to the ability of an organism to replace or restore lost or damaged tissues or organs. This process involves the formation of new cells or tissues from the injured part of the body.

2. **Identifying Regenerative Organs in Mammals**: Among mammals, different organs have varying capacities for regeneration. It is essential to identify which organs can regenerate effectively.

3. **Evaluating the Options**: The options provided are:
- Brain
- Liver
- Lung
- Urinary Bladder

4. **Analyzing Each Option**:
- **Brain**: While some neurogenesis (the formation of new neurons) occurs in certain areas of the brain, it is limited and does not equate to full regeneration of brain tissue.
- **Liver**: The liver is known for its remarkable regenerative capacity. It can regenerate after surgical removal or injury, making it a unique organ in mammals.
- **Lung**: The lung has some regenerative ability, but it is not as significant as that of the liver.
- **Urinary Bladder**: The urinary bladder does not have a significant regenerative capability compared to the liver.

5. **Conclusion**: Based on the analysis, the only organ in mammals that can regenerate effectively is the liver.

**Final Answer**: Mammals can regenerate the liver.

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