Anatomy HESI A2 Practice Test

Correct Answer: C

Rationale: The correct answer is C: To store urine. The urinary bladder is a muscular organ that serves as a reservoir for urine produced by the kidneys. It temporarily stores urine until it is ready to be excreted from the body. Filtering blood (A) is the function of the kidneys, storing and concentrating bile (B) is the function of the gallbladder, and absorbing nutrients (D) mostly occurs in the small intestine. Therefore, the main function of the urinary bladder is to store urine before it is eliminated from the body.

Correct Answer: B

Rationale: The correct answer is B: Occipital lobe. The occipital lobe is primarily responsible for processing visual information. It contains the primary visual cortex, which receives and interprets visual stimuli from the eyes. This region processes shapes, colors, and motion. The temporal lobe (A) is involved in memory and auditory processing. The parietal lobe (C) is responsible for spatial awareness and sensory information integration. The frontal lobe (D) is associated with executive functions and motor skills. Thus, the occipital lobe is the correct choice for processing visual information.

Correct Answer: B

Rationale: The correct answer is B: To speed up chemical reactions. Enzymes act as biological catalysts that accelerate chemical reactions by lowering the activation energy required for the reactions to occur. They do not produce energy (choice A), transport molecules (choice C), or repair tissues (choice D). Enzymes specifically facilitate reactions without being consumed in the process, making them crucial for various metabolic pathways in the body.

Correct Answer: C

Rationale: Platelets play a crucial role in blood clotting, known as hemostasis. Step 1: When a blood vessel is damaged, platelets adhere to the site to form a temporary plug. Step 2: Platelets release chemicals that attract more platelets and help in clot formation. Step 3: This clotting process prevents excessive bleeding. Choice A is incorrect as oxygen is primarily carried by red blood cells. Choice B is incorrect as fighting infections is mainly done by white blood cells. Choice D is incorrect as nutrient transport is mainly carried out by the plasma in the blood.

Correct Answer: B

Rationale: The correct answer is B: Mouth. Digestion begins in the mouth where food is mechanically broken down by chewing and chemically broken down by enzymes in saliva. This initial process prepares food for further digestion in the stomach and small intestine. The stomach (A) primarily functions to further break down food through acid and enzymes. The small intestine (C) is where the majority of nutrients are absorbed, not where digestion begins. The esophagus (D) is responsible for transporting food from the mouth to the stomach, but it does not participate in the actual digestion process.