Why is functional insulin produced considered better than used earlier by diabetic patients ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Insulin:**
- Insulin is a hormone produced by the beta cells of the pancreas. Its primary function is to regulate blood glucose levels by converting excess glucose into glycogen, which is stored in the liver.

2. **The Problem with Earlier Insulin:**
- Previously, insulin was extracted from the pancreases of slaughtered animals (like pigs and cows). This animal-derived insulin often led to allergic reactions in some diabetic patients because it was a foreign protein to their bodies.

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