HESI A2 Anatomy and Physiology Practice Exam

Correct Answer: D

Rationale: The correct answer is D: Melatonin. The pineal gland is responsible for producing melatonin, a hormone that regulates the sleep-wake cycle. It is released in response to darkness, helping to signal the body that it is time to sleep. Corticosteroid (A) is produced by the adrenal glands, oxytocin (B) is produced by the hypothalamus and released by the pituitary gland, and prolactin (C) is produced by the pituitary gland. Therefore, the correct answer is D as it directly relates to the function of the pineal gland.

Correct Answer: D

Rationale: The correct answer is D, Achilles tendon, as it is a posterior feature of the human leg. The Achilles tendon is located at the back of the ankle, connecting the calf muscles to the heel bone. This tendon is crucial for various movements like walking, running, and jumping. Rationale: 1. The Achilles tendon is a well-known structure located at the posterior aspect of the leg. 2. It plays a vital role in the functioning of the lower leg muscles. 3. The other choices (A: Patella, B: Quadriceps sartorius, C: Triceps brachii) are not located at the posterior aspect of the leg and are not directly related to the function of the lower leg muscles.

Correct Answer: C

Rationale: The correct answer is C: Tofu. Tofu, made from soybeans, is a complete protein source, providing all essential amino acids needed by the body. It is a significant protein source for individuals on a vegan diet. Eggs (A) and fish (B) are animal products and not suitable for a vegan diet. Leafy greens (D) are not a significant source of protein compared to tofu and may not provide enough protein for a person following a vegan diet.

Correct Answer: C

Rationale: Trypsin is a digestive enzyme produced in the pancreas that specifically breaks down proteins into smaller peptides. It acts in the small intestine, targeting peptide bonds between amino acids. This process aids in protein digestion and absorption. Choices A, B, and D are incorrect as trypsin does not break down fats, starch, or nucleic acids in the body.

Correct Answer: D

Rationale: The correct answer is D, Integumentary system. Sebaceous glands are located in the skin, which is part of the integumentary system. These glands secrete sebum to lubricate and protect the skin. The endocrine system (choice A) regulates hormones, not sebum production. The digestive system (choice B) processes food, not related to sebaceous glands. The respiratory system (choice C) is responsible for gas exchange, not sebum secretion. Therefore, the integumentary system is the correct choice.