Depressed activity of osteblasts lead to disease called ………….. .

Explanation

**Step-by-Step Solution:**

1. **Understanding Osteoblasts**: Osteoblasts are specialized cells responsible for the formation of new bone tissue. They play a crucial role in bone growth and repair.

2. **Identifying Depressed Activity**: The question mentions "depressed activity of osteoblasts," which means that these cells are not functioning effectively. This leads to insufficient new bone formation.

3. **Consequences of Depressed Osteoblast Activity**: When osteoblasts are not active enough to form new bone, the existing bone tissue can become weak and brittle over time. This condition can lead to various bone-related diseases.

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