What are the causes of inbuilt tendency of variations ?

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Variations**: Variations refer to the differences that occur among individuals of the same species. These variations can be caused by external factors (like environmental influences) or internal factors (inbuilt tendencies).

2. **Errors During DNA Replication**: One of the primary causes of inbuilt variations is errors that occur during the replication of DNA. DNA replication is a process where a DNA molecule makes a copy of itself, and this process is facilitated by an enzyme known as DNA polymerase.

3. **Accuracy of DNA Polymerase**: DNA polymerase is highly accurate, with an accuracy rate of 99.9999%. However, there is still a small chance (0.0001%) that errors can occur during this replication process.

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