Read the following statements carefully ( A - D ) :
A . Thymosin hormone helps T -lymphocytes to provide cell-mediated immunity .
B. Calcitonin ormone increases blood calcium level and is hypercalcemic.
C. Melanin hormones from the pineal gland, regulate the 24 hours (diurnal ) rhythm cycle.
D. Epinephrine and norepinephrine hormones are called catacholamines.
How many statements /s from above is /are correct ?

Options

A. Four
B. Three
C. Two
D. one

Answer

To solve the question, we will analyze each statement (A - D) one by one to determine their correctness.

### Step 1: Analyze Statement A
**Statement A:** Thymosin hormone helps T-lymphocytes to provide cell-mediated immunity.

- **Analysis:** Thymosin is indeed a hormone produced by the thymus gland, and it plays a crucial role in the maturation and differentiation of T-lymphocytes, which are essential for cell-mediated immunity.
- **Conclusion:** This statement is **correct**.

### Step 2: Analyze Statement B
**Statement B:** Calcitonin hormone increases blood calcium level and is hypercalcemic.

- **Analysis:** Calcitonin is a hormone produced by the thyroid gland that actually lowers blood calcium levels by inhibiting osteoclast activity in bones and promoting calcium excretion in the kidneys. Therefore, it is a hypocalcemic hormone, not hypercalcemic.
- **Conclusion:** This statement is **incorrect**.

### Step 3: Analyze Statement C
**Statement C:** Melanin hormones from the pineal gland regulate the 24 hours (diurnal) rhythm cycle.

- **Analysis:** The hormone responsible for regulating the circadian rhythm (24-hour cycle) is melatonin, which is produced by the pineal gland. Melanin, on the other hand, is a pigment responsible for skin color and is not a hormone that regulates the diurnal rhythm.
- **Conclusion:** This statement is **incorrect**.

### Step 4: Analyze Statement D
**Statement D:** Epinephrine and norepinephrine hormones are called catecholamines.

- **Analysis:** Epinephrine (adrenaline) and norepinephrine (noradrenaline) are indeed classified as catecholamines. They are produced in the adrenal medulla and play a significant role in the body's fight-or-flight response.
- **Conclusion:** This statement is **correct**.

### Final Conclusion
After analyzing all statements:
- **Correct Statements:** A and D
- **Incorrect Statements:** B and C

Thus, **2 statements are correct.**