1. Calcitonin, a hormone that helps regulate calcium levels, is produced by the:

A. Thyroid gland
B. Parathyroid gland
C. Thymus gland
D. Adrenal gland

Correct answer: A

Rationale: The correct answer is A: "Thyroid gland." Calcitonin is a hormone produced by the thyroid gland that helps regulate calcium levels in the body. It works in opposition to parathyroid hormone, which is produced by the parathyroid gland. The thymus gland is responsible for immune function, while the adrenal gland produces hormones like cortisol and adrenaline. Therefore, the thyroid gland is the specific gland responsible for producing calcitonin to regulate calcium levels in the body.

2. What is the functional group present in amines?

A. Hydroxyl
B. Carbonyl
C. Amine
D. Nitro

Correct answer: C

Rationale: Amines have the functional group -NHâ‚‚. The other choices are associated with different functional groups.

3. A decorative box has a rectangular base (20cm by 15cm) and a hemispherical top with the same diameter as the base. What is the total surface area of the box (excluding the base)?

A. 825 sq cm
B. 1075 sq cm
C. 1325 sq cm
D. 1575 sq cm

Correct answer: C

Rationale: Calculate the surface area of the lateral sides and the hemisphere, then add them up.

4. What type of nutrients require minimal digestion before absorption?

A. Carbohydrates
B. Proteins
C. Fats
D. Vitamins

Correct answer: D

Rationale: Rationale: A) Carbohydrates: Carbohydrates require digestion by enzymes in the mouth, stomach, and small intestine before they can be broken down into simple sugars for absorption. B) Proteins: Proteins need to be broken down into amino acids by stomach acid and digestive enzymes in the stomach and small intestine before they can be absorbed. C) Fats: Fats require bile from the gallbladder to emulsify them into smaller droplets for enzymes to break them down into fatty acids and glycerol for absorption. D) Vitamins: Vitamins are organic compounds that are already in a form that can be readily absorbed by the body without extensive digestion. They are absorbed directly into the bloodstream from the small intestine and do not require significant breakdown before absorption.

5. What principle explains the relationship between pressure, volume, and temperature for ideal gases?

A. Law of conservation of energy
B. Newton's laws of motion
C. Ideal gas law
D. Archimedes' principle

Correct answer: C

Rationale: The ideal gas law (PV = nRT) relates pressure, volume, and temperature for ideal gases at constant number of moles and temperature.

6. The term "barn" is a unit commonly used in nuclear physics to quantify:

A. Energy (Electron volts are the standard unit for energy in nuclear physics)
B. Radioactivity
C. Nuclear cross-section
D. Half-life

Correct answer: C

Rationale: The term 'barn' is a unit of measurement used in nuclear physics to quantify nuclear cross-section. Nuclear cross-section refers to the measure of the probability of a specific interaction occurring between particles during a nuclear reaction. The term 'barn' was coined based on its relation to the physical size of a nucleus, as it is a small unit of area used to describe the likelihood of a particle interacting with a nucleus. It is not used to quantify energy, radioactivity, or half-life, making options A, B, and D incorrect in this context.