In animals, active mitosis can be observed :-

Options

A. At the base of nails
B. At the apex of hairs
C. Dermis of skin
D. Glands

Answer

To answer the question "In animals, active mitosis can be observed:", we will analyze the options provided and determine where mitosis is actively taking place in animal cells.

### Step-by-Step Solution:

1. **Understanding Mitosis**: Mitosis is a process of cell division that results in two identical daughter cells, each with the same number of chromosomes as the parent cell. It is crucial for growth, repair, and maintenance of tissues in animals.

2. **Identifying Active Sites of Mitosis**: In animals, active mitosis occurs in areas where rapid cell division is necessary. This includes regions where growth is occurring or where cells are being replaced.

3. **Analyzing the Options**:
- **Option 1: Base of Nails**: This is a region where new cells are produced to replace those that are lost. Active mitosis occurs here to facilitate nail growth.
- **Option 2: Apex of Nails**: This is the tip of the nail, where cells are already dead and keratinized. Mitosis does not occur here.
- **Option 3: Dermis of Skin**: While the dermis is a living layer of skin, the active mitosis primarily occurs in the basal layer of the epidermis, not the dermis itself.
- **Option 4: Glands**: Glands are involved in secretion and may have some cell turnover, but they are not primarily sites of active mitosis.

4. **Conclusion**: Based on the analysis, the correct answer is **Option 1: Base of Nails**, as this is where active mitosis is observed in animals.

### Final Answer:
Active mitosis in animals can be observed at the **base of nails**.

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