What are the major features of embryonic development at the After first months of pregnancy?

Explanation

### Step-by-Step Solution:

1. **Understanding the Timeline**: The question focuses on the major features of embryonic development specifically at the end of the first month of pregnancy. It is crucial to recognize that this period is critical for the initial stages of fetal development.

2. **Formation of the Heart**: By the end of the first month, one of the most significant developments is the formation of the heart. The heart is one of the first organs to develop in the embryo, and its formation is a key indicator of healthy embryonic development.

3. **Heartbeat Detection**: Along with the formation of the heart, the heartbeat becomes detectable by the end of the first month. This is an important milestone, as it signifies that the embryo is developing properly and is receiving the necessary blood supply.

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