Anatomy and Physiology Hesi A2 Practice Test

Correct Answer: B

Rationale: The correct answer is B: To absorb nutrients. The small intestine is responsible for absorbing nutrients from digested food into the bloodstream for distribution to the rest of the body. This process involves the absorption of proteins, carbohydrates, fats, vitamins, and minerals. The small intestine does not primarily break down food (A), as this is mainly done in the stomach. While the small intestine does secrete digestive enzymes (C), its primary function is absorption. Lastly, the small intestine does not store glucose (D), as glucose is stored in the liver and muscles.

Correct Answer: C

Rationale: The motor cortex is located in the front portion of the parietal lobe. This area is specifically known as the primary motor cortex, which is responsible for planning, controlling, and executing voluntary movements. It sends signals to the muscles to initiate movement. Option A (back of the head) is incorrect as that area is primarily related to visual processing. Option B (top middle portion of the parietal lobe) is incorrect as that area is more associated with somatosensory processing. Option D (around the auditory cortex) is incorrect as the auditory cortex is responsible for processing auditory information, not motor functions.

Correct Answer: B

Rationale: The correct answer is B: Adrenaline. Adrenal glands release adrenaline during stress as part of the fight-or-flight response. Adrenaline increases heart rate, blood flow to muscles, and boosts energy. Insulin (A) regulates blood sugar, not stress response. Melatonin (C) regulates sleep-wake cycles. Cortisol (D) is released during stress but is not the primary hormone for immediate stress response like adrenaline.

Correct Answer: B

Rationale: The correct answer is B: Nucleus. The nucleus contains the genetic material in the form of DNA, which carries the instructions for the cell's functions. The DNA is organized into chromosomes within the nucleus. Ribosomes (A) are involved in protein synthesis but do not contain genetic material. Mitochondria (C) have their own DNA but do not house the majority of the cell's genetic material. Endoplasmic reticulum (D) is involved in protein synthesis and lipid metabolism but does not contain genetic material. The nucleus is the control center of the cell, housing the genetic information essential for cell function and replication.

Correct Answer: B

Rationale: The correct answer is B: Mitochondria. Mitochondria are known as the powerhouse of the cell because they are responsible for producing energy in the form of ATP through cellular respiration. They contain enzymes necessary for the production of ATP, which is the main energy currency of the cell. The other choices are incorrect because: A: Nucleus - Responsible for controlling cell activities and storing genetic material. C: Ribosome - Responsible for protein synthesis, not energy production. D: Golgi apparatus - Responsible for processing and packaging proteins for secretion, not energy production.