Which of the following statements are true/false ?
i. Thyrocalcitonin regulates the homeostasis of blood calcium levels.
ii. Oxytocin stimulates contraction of uterine muscles during birth.
iii. ''Grave's disease'' is caused by malfunctioning of the adrenal gland.
iv. ADH stimulates the absorption of water and increase urine production.

Options

A. I and ii are true , ii and iv are false
B. I and ii are true , iii and iv are false
C. I and iv are false, ii and iii are true
D. I, ii, iii, are true iv only false

Answer

To determine the truthfulness of the statements provided, let's analyze each one step by step:

### Step 1: Analyze Statement i
**Statement:** Thyrocalcitonin regulates the homeostasis of blood calcium levels.
**Analysis:** Thyrocalcitonin, also known simply as calcitonin, is a hormone produced by the thyroid gland that helps regulate calcium levels in the blood. It lowers blood calcium levels by inhibiting osteoclast activity in bones and promoting calcium excretion in the kidneys.
**Conclusion:** This statement is **True**.

### Step 2: Analyze Statement ii
**Statement:** Oxytocin stimulates contraction of uterine muscles during birth.
**Analysis:** Oxytocin is a hormone that plays a crucial role in childbirth. It stimulates the contraction of the uterine muscles during labor, facilitating the delivery of the baby.
**Conclusion:** This statement is **True**.

### Step 3: Analyze Statement iii
**Statement:** "Grave's disease" is caused by malfunctioning of the adrenal gland.
**Analysis:** Grave's disease is an autoimmune disorder that leads to overactivity of the thyroid gland (hyperthyroidism). It is not related to the adrenal gland but rather to the thyroid gland.
**Conclusion:** This statement is **False**.

### Step 4: Analyze Statement iv
**Statement:** ADH stimulates the absorption of water and increases urine production.
**Analysis:** Antidiuretic hormone (ADH), also known as vasopressin, promotes water reabsorption in the kidneys, which decreases urine production. Therefore, while it does stimulate water absorption, it does not increase urine production; it actually decreases it.
**Conclusion:** This statement is **False**.

### Final Summary of Statements:
- i. True
- ii. True
- iii. False
- iv. False

### Final Answer:
The correct evaluation is:
- Statement i: True
- Statement ii: True
- Statement iii: False
- Statement iv: False