Correct Answer: B

Rationale: The correct answer is B: Approximately 30. The human skull is composed of 22 bones that are fused together. These 22 bones consist of 8 cranial bones and 14 facial bones, totaling approximately 30 bones in total. Choices A, C, and D are incorrect because the human skull does not have as few as 5 bones, as many as 60 bones, or as many as 210 bones. Understanding the basic anatomy of the skull helps in identifying the correct number of bones it comprises.

Correct Answer: C

Rationale: The lateral side of the right knee is the side that is farthest from the left knee when looking at the knee joint from the front. The term 'lateral' refers to the side of the body that is farther away from the midline or center of the body. In this case, the lateral side of the right knee is on the outer side of the knee joint, away from the other knee. Choice A is incorrect as the kneecap is located at the front of the knee. Choice B is incorrect as it describes the medial side, not the lateral side. Choice D is incorrect as it refers to the underside, which is not related to the lateral aspect of the knee.

Correct Answer: A

Rationale: The vena cavae are large veins responsible for returning deoxygenated blood from the body to the heart. They empty into the right atrium of the heart. From the right atrium, the blood is then pumped into the right ventricle before being sent to the pulmonary circulation for oxygenation, making choice A, 'right atrium,' the correct answer. Choices B, C, and D are incorrect because the vena cavae do not empty into the ventricles of the heart; instead, they deliver blood to the atria.

Correct Answer: A

Rationale: Beriberi is a disease caused by a deficiency of thiamine, also known as vitamin B1. Thiamine is essential for the proper functioning of the nervous system and energy metabolism in the body. Without enough thiamine, individuals may develop symptoms such as weakness, fatigue, nerve damage, and heart problems, which are characteristic of beriberi. Vitamin C (choice B), niacin (choice C), and protein (choice D) deficiencies can cause other health issues but are not directly related to beriberi.

Correct Answer: A

Rationale: The correct answer is A: Breaking down starch. Amylase is an enzyme that specifically functions to break down starch into smaller sugar molecules such as maltose and glucose. This process is essential for the digestion and absorption of carbohydrates in the body. Choices B, C, and D are incorrect because amylase does not digest fat, break down protein, or absorb water; its primary function lies in starch digestion.