1. Which hormone plays a key role in stimulating the release of milk from breast tissue after childbirth?

A. Follicle-stimulating hormone (FSH)
B. Luteinizing hormone (LH)
C. Prolactin
D. Estrogen

Correct answer: C

Rationale: The correct answer is C: Prolactin. Prolactin is the hormone responsible for stimulating the production and release of milk from breast tissue after childbirth. It is produced by the pituitary gland and plays a crucial role in lactation. FSH and LH are reproductive hormones involved in the menstrual cycle and ovulation, not milk production. Estrogen is a sex hormone that plays a role in the development of female reproductive organs. Therefore, the hormone that specifically stimulates milk release from breast tissue after childbirth is prolactin.

2. What is the difference between mass and weight?

A. Mass is the force exerted on an object due to gravity, whereas weight is the amount of matter in an object.
B. Mass is a measure of inertia, whereas weight is a measure of the force of gravity acting on an object.
C. Mass is measured in pounds, whereas weight is measured in kilograms.
D. Mass is a vector quantity, whereas weight is a scalar quantity.

Correct answer: b

Rationale: Mass is the amount of matter in an object, while weight is the force exerted on an object due to gravity.

3. Negative feedback mechanisms are crucial in the endocrine system to:

A. Increase hormone production continuously
B. Maintain hormone levels within a specific range
C. Cause a constant release of hormones
D. Disrupt communication between glands

Correct answer: B

Rationale: The correct answer is B: 'Maintain hormone levels within a specific range.' Negative feedback mechanisms in the endocrine system are essential for regulating hormone levels. These mechanisms work to counteract any deviations from the set point, ensuring that hormone levels remain balanced and within the optimal range for proper physiological function. Continuous hormone production (A) or constant release of hormones (C) would lead to imbalances and potential harm to the body. Disrupting communication between glands (D) would hinder the coordination necessary for maintaining homeostasis. Therefore, option B is the best choice as it highlights the critical role of negative feedback in keeping hormone levels stable and regulated.

4. What is the main difference between a telescope and a microscope?

A. Telescopes magnify distant objects, while microscopes magnify small objects.
B. Telescopes use lenses, while microscopes use mirrors.
C. Telescopes collect light, while microscopes emit light.
D. They both magnify objects but serve different purposes.

Correct answer: A

Rationale: While both instruments magnify objects, telescopes are designed to observe distant objects, while microscopes are used to magnify tiny objects close to the observer.

5. Which of the following is the main function of the kidneys?

A. To filter waste products from the blood
B. To produce urine
C. To regulate blood pressure
D. To produce hormones that help to control blood sugar levels

Correct answer: A

Rationale: Rationale: A) To filter waste products from the blood: The main function of the kidneys is to filter waste products, excess ions, and water from the bloodstream to form urine, which is then excreted from the body. This process helps maintain the body's internal environment by regulating the balance of electrolytes, fluid volume, and pH levels. B) To produce urine: While the kidneys do produce urine as a result of filtering the blood, the primary function is to filter waste products rather than solely producing urine. C) To regulate blood pressure: The kidneys do play a role in regulating blood pressure by controlling the volume of blood and the concentration of electrolytes in the body, but their main function is waste filtration. D) To produce hormones that help to control blood sugar levels: While the kidneys do produce hormones like erythropoietin and renin that play a role in various physiological processes, such as red

6. The tiny air sacs in the lungs where gas exchange takes place are called:

A. Bronchi
B. Trachea
C. Alveoli
D. Pleura

Correct answer: A

Rationale: The correct answer is C: 'Alveoli.' Alveoli are the tiny air sacs in the lungs where gas exchange takes place. Oxygen from the air is diffused into the blood, and carbon dioxide from the blood is diffused into the air in the alveoli. Bronchi (option A) are the large air passages that lead from the trachea into the lungs. Trachea (option B) is the windpipe that connects the larynx to the bronchi. Pleura (option D) is a thin membrane that surrounds the lungs and lines the chest cavity. Understanding these structures is essential for comprehending respiratory function and gas exchange in the human body.