HESI A2 Anatomy and Physiology 2023

Correct Answer: A

Rationale: The primary function of the cardiovascular system is to transport oxygen and nutrients to cells throughout the body. This is achieved through the circulation of blood by the heart and blood vessels. Oxygen is vital for cellular respiration, and nutrients are essential for cell function. Regulating body temperature is primarily the role of the integumentary and nervous systems, not the cardiovascular system. Removing waste products is mainly the function of the excretory system. Hormone production is primarily controlled by the endocrine system, not the cardiovascular system. Therefore, choice A is correct as it directly aligns with the main purpose of the cardiovascular system.

Correct Answer: B

Rationale: The correct answer is B: Tendons. Tendons are the connective tissue type that attaches muscles to bones. They are strong, fibrous cords that transmit the force generated by muscles to the bones, allowing movement. Ligaments (A) connect bones to other bones, not muscles. Cartilage (C) is a type of supportive tissue found in joints but does not attach muscles to bones. Fascia (D) is a connective tissue that surrounds muscles and other structures but does not directly attach muscles to bones.

Correct Answer: A

Rationale: The correct answer is A: Cerebellum. The cerebellum is responsible for controlling balance and coordination. It receives information from the sensory systems, such as the inner ear and visual system, and integrates this information to coordinate smooth movements. The cerebrum (B) is mainly involved in higher brain functions like thinking and problem-solving. The medulla oblongata (C) controls vital functions such as breathing and heart rate. The brainstem (D) is responsible for basic life functions like breathing and consciousness. Thus, the cerebellum is the specific region of the brain that directly controls balance and coordination.

Correct Answer: C

Rationale: The correct answer is C: Retina. The retina contains specialized cells called cones that are responsible for color vision. Cones are sensitive to different wavelengths of light, allowing us to perceive colors. The cornea (A) focuses light onto the retina, the iris (B) controls the amount of light entering the eye, and the lens (D) helps to focus light onto the retina, but they do not directly contribute to color vision.

Correct Answer: B

Rationale: The correct answer is B: Skin. The skin is the largest organ in the human body by surface area, covering about 20 square feet on average. It serves as a protective barrier against external elements and plays a crucial role in regulating body temperature. The liver (A), brain (C), and heart (D) are important organs, but they are not the largest in terms of size or surface area. Therefore, the correct choice is the skin.