HESI A2 Anatomy and Physiology Quizlet

Correct Answer: A

Rationale: The correct answer is A: Insulin. The pancreas produces insulin, a hormone that helps regulate blood sugar levels by facilitating the uptake of glucose into cells. Insulin is crucial in maintaining normal blood sugar levels. Glucagon (choice B) is also produced by the pancreas, but it works in the opposite way to insulin by increasing blood sugar levels. Somatostatin (choice C) is produced by the pancreas and has various functions, including inhibiting the release of insulin and glucagon. Cortisol (choice D) is produced by the adrenal glands, not the pancreas, and plays a role in stress response and metabolism.

Correct Answer: B

Rationale: The correct answer is B: Mitochondria. Mitochondria are known as the powerhouse of the cell because they are responsible for energy production through the process of cellular respiration. They produce ATP, the main energy currency of the cell. The other choices are incorrect because the nucleus is responsible for storing genetic material, ribosomes are involved in protein synthesis, and the Golgi apparatus is responsible for packaging and transporting proteins. Therefore, only the mitochondria play a direct role in energy production within the cell.

Correct Answer: C

Rationale: The correct answer is C: Smooth muscle. Smooth muscle tissue is found in the walls of hollow organs such as the intestines, blood vessels, and bladder. It is involuntary, non-striated, and capable of sustained contractions. Skeletal muscle (A) is attached to bones and is under voluntary control. Cardiac muscle (B) is found in the heart and has a unique branching structure. Striated muscle (D) includes both skeletal and cardiac muscle, but smooth muscle specifically lines hollow organs.

Correct Answer: B

Rationale: The correct answer is B: Pivot joint. Pivot joints allow for rotational movement around a single axis. This type of joint is found in the neck, allowing the head to rotate side to side. Hinge joints (choice A) allow movement in one plane like the elbow. Ball and socket joints (choice C) allow for a wide range of movement in multiple directions like the hip and shoulder. Saddle joints (choice D) allow for movement in two axes like the thumb. Therefore, the correct answer is pivot joint as it specifically allows for rotational movement around a single axis.

Correct Answer: B

Rationale: The primary function of the skin in the integumentary system is to protect the body from external damage. The skin acts as a barrier against pathogens, UV radiation, chemicals, and physical injuries. It also helps regulate body temperature, but its main role is protection. Skin does not produce red blood cells (bone marrow does) or hormones (endocrine glands do). Therefore, choice B is correct as it aligns with the main function of the skin.