One of the following is antagonistic :

Options

A. FSH & LH
B. Oxytocin & Vassopressin
C. Nor adrenaline & adrenaline
D. Insulin & Glucagon

Answer

To determine which of the following hormone pairs is antagonistic, we need to analyze each pair based on their functions:

1. **FSH and LH**: Both Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH) are gonadotropins produced by the pituitary gland. They stimulate gonadal activity and work together to regulate reproductive processes. Therefore, they are not antagonistic.

2. **Oxytocin and Vasopressin**: Oxytocin is involved in uterine contractions and milk ejection during breastfeeding, while Vasopressin (also known as Antidiuretic Hormone, ADH) is responsible for water reabsorption in the kidneys. Although they have different functions, they do not work in opposition to each other, so they are not antagonistic.

3. **Adrenaline and Non-Adrenaline**: Both of these hormones are produced by the adrenal medulla and are involved in the body's fight-or-flight response. They have similar effects, such as increasing heart rate and blood flow, and thus are not antagonistic.

4. **Insulin and Glucagon**: Insulin is produced by the pancreas and lowers blood glucose levels by facilitating the uptake of glucose by cells. In contrast, Glucagon, also produced by the pancreas, raises blood glucose levels by promoting the release of glucose from the liver. Since they have opposite effects on blood glucose levels, they are indeed antagonistic to each other.

Based on this analysis, the correct answer is **Insulin and Glucagon**.

### Step-by-Step Solution:
1. **Identify the hormone pairs**: FSH and LH, Oxytocin and Vasopressin, Adrenaline and Non-Adrenaline, Insulin and Glucagon.
2. **Analyze FSH and LH**: Both stimulate gonadal activity; they are not antagonistic.
3. **Analyze Oxytocin and Vasopressin**: Different functions but not oppositional; they are not antagonistic.
4. **Analyze Adrenaline and Non-Adrenaline**: Similar functions in emergency response; they are not antagonistic.
5. **Analyze Insulin and Glucagon**: Opposite effects on blood glucose levels; they are antagonistic.
6. **Conclude**: The antagonistic pair is Insulin and Glucagon.