Which one of the following statements is correct?

Options

A. Hormones produced by the ovary affects uterine contractions.
B. Hormones produced by intestine stimulates heartbeat
C. Hormones produced by kidney regulates general blood pressure
D. Hormones produced by thyroid regulates general metabolism.

Explanation

To determine which statement is correct regarding hormones and their functions, we will analyze each option provided:

1. **Option 1: Hormones produced by the ovary affect uterine contractions.**
- The ovaries produce estrogen and progesterone, which primarily regulate the menstrual cycle and prepare the uterus for pregnancy. However, they do not directly affect uterine contractions. The hormone responsible for stimulating uterine contractions during childbirth is oxytocin, which is produced by the pituitary gland. Therefore, this statement is incorrect.

2. **Option 2: Hormones produced by the intestine stimulate heartbeat.**
- The intestines produce hormones such as gastrin and secretin, which are involved in digestion and do not have a direct role in stimulating the heartbeat. The heartbeat is primarily regulated by the autonomic nervous system and hormones like adrenaline (epinephrine) produced by the adrenal glands. Thus, this statement is also incorrect.

3. **Option 3: Hormones produced by the kidney regulate general blood pressure.**
- The kidneys produce hormones such as renin, which plays a crucial role in the regulation of blood pressure through the renin-angiotensin-aldosterone system. This statement is correct as the kidneys are indeed involved in regulating blood pressure.

4. **Option 4: Hormones produced by the thyroid regulate general metabolism.**
- The thyroid gland produces hormones like thyroxine (T4) and triiodothyronine (T3), which are essential for regulating metabolism in the body. This statement is also correct.

Now, we have two statements that can be considered correct: Option 3 and Option 4. However, since the question asks for one correct statement, we will choose the one that is more universally acknowledged in terms of its primary function.

**Final Answer: Option 4 - Hormones produced by the thyroid regulate general metabolism.**