Anatomy HESI A2 Practice Test

Correct Answer: A

Rationale: The primary function of the cardiovascular system is to pump blood throughout the body. This process ensures oxygen and nutrients are delivered to tissues and organs, while also removing waste products. Choice A is correct as it directly relates to the main role of the cardiovascular system. Choices B, C, and D are incorrect because although the cardiovascular system indirectly contributes to delivering nutrients, regulating body temperature, and protecting against infection through immune responses, these are not its primary functions.

Correct Answer: A

Rationale: The correct answer is A: They secrete chemicals into the blood. Endocrine glands are ductless glands that secrete hormones directly into the bloodstream. This allows the hormones to travel throughout the body to target organs and tissues. Choices B, C, and D are incorrect because endocrine glands do not secrete enzymes into ducts (B), produce sweat (C), or produce saliva (D). These functions are typically associated with exocrine glands that have ducts for secretion.

Correct Answer: A

Rationale: The primary function of the hypothalamus is to regulate body balance and thermoregulation. It maintains homeostasis by controlling various physiological processes such as body temperature, blood pressure, and electrolyte balance. It also plays a role in regulating hormonal functions through the pituitary gland. Choices B, C, and D are incorrect because hunger, thirst, sleep, circadian rhythms, and voluntary movements are primarily controlled by other brain regions such as the amygdala, pineal gland, and motor cortex, respectively.

Correct Answer: B

Rationale: The correct answer is B: Medulla oblongata. This brain part is located in the brainstem and controls vital functions such as heart rate and blood pressure. It contains the cardiovascular center which regulates these functions through autonomic nervous system pathways. The other choices (A: Cerebellum, C: Hypothalamus, D: Pons) do not have direct control over heart rate and blood pressure regulation. The cerebellum is mainly responsible for motor coordination, the hypothalamus regulates body temperature, hunger, and thirst, and the pons is involved in sleep and arousal. Thus, the medulla oblongata is the correct choice for regulating heart rate and blood pressure.

Correct Answer: B

Rationale: The correct answer is B: Larynx. The larynx is an organ of the respiratory system responsible for producing sound and protecting the trachea during swallowing. It is located in the throat region and contains vocal cords. The brain (A) is part of the nervous system, not the respiratory system. The urethra (C) is part of the urinary system, and the pancreas (D) is part of the digestive system. Therefore, the larynx is the only choice directly related to the respiratory system.