HESI A2 Anatomy and Physiology 2023

Correct Answer: B

Rationale: The correct answer is B: Support and protection. The skeletal system provides structural support for the body and protects internal organs. It also helps with movement, stores minerals, and produces blood cells. Choices A, C, and D are incorrect because the production of red blood cells occurs in the bone marrow, secretion of hormones is primarily the function of the endocrine system, and regulation of body temperature is controlled by the nervous system and other mechanisms, not the skeletal system.

Correct Answer: A

Rationale: The correct answer is A: Nucleus. The genetic material, DNA, is located within the nucleus of a cell. This is where the DNA is stored and protected. The nucleus also houses the nucleolus, which is responsible for producing ribosomes. Mitochondria (B) is responsible for energy production, not genetic material storage. Ribosomes (C) are involved in protein synthesis, not DNA storage. Golgi apparatus (D) is responsible for packaging and processing proteins, not housing genetic material.

Correct Answer: C

Rationale: The correct answer is C: Medulla oblongata. The medulla oblongata is located in the brainstem and is responsible for regulating essential functions such as heart rate and breathing. It contains vital centers that control autonomic functions, including the cardiovascular and respiratory systems. The medulla receives inputs from various sensory receptors and sends signals to the heart and lungs to maintain homeostasis. The other choices are incorrect because: A: Cerebrum is primarily responsible for higher brain functions such as thinking and voluntary movements. B: Cerebellum is involved in coordination and balance, not in regulating heart rate and breathing. D: Hypothalamus plays a role in regulating body temperature, hunger, and thirst, but not specifically in controlling heart rate and breathing.

Correct Answer: A

Rationale: The correct answer is A: Cerebellum. The cerebellum is responsible for balance and coordination as it receives sensory information from the inner ear and muscles to control movement. It coordinates muscle actions and maintains posture. The cerebrum (B) is responsible for higher brain functions, the medulla oblongata (C) controls basic life functions like breathing and heart rate, and the hypothalamus (D) regulates body temperature, hunger, and thirst. Thus, the cerebellum is the most appropriate choice for balance and coordination.

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.