HESI A2 Anatomy and Physiology 2023

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: A

Rationale: The correct answer is A: Pancreas. The pancreas is responsible for producing insulin, a hormone that helps regulate blood sugar levels. It contains clusters of cells called islets of Langerhans, which specifically produce insulin. The liver (B) is involved in storing glucose and producing bile, not insulin. The gallbladder (C) stores bile produced by the liver and aids in digestion, not insulin production. The kidneys (D) filter blood and regulate fluid balance, but do not produce insulin. Therefore, the pancreas is the organ responsible for insulin production in the body.

Correct Answer: C

Rationale: The correct answer is C: Front portion of the parietal lobe. This area is known as the primary motor cortex, responsible for planning, control, and execution of voluntary movements. It receives input from other brain regions involved in movement. Choices A, B, and D are incorrect because the top, middle portion of the parietal lobe is involved in sensory processing, the back of the head is associated with the occipital lobe responsible for vision, and around the auditory cortex is involved in processing auditory information, respectively.

Correct Answer: B

Rationale: The ulnar nerve innervates the arm, specifically the pinky finger, ring finger, and part of the hand. Damage to the ulnar nerve will lead to decreased sensation in these areas. Therefore, the correct answer is B (Arm). The other choices are incorrect because the ulnar nerve does not supply sensation to the Leg (A), Face (C), or Abdomen (D).

Correct Answer: B

Rationale: The correct answer is B: Pinna. The pinna, also known as the auricle, is the most visible part of the ear located on the outside of the head. It helps collect sound waves and directs them into the ear canal. The other choices are incorrect because: A: Cochlea is a spiral-shaped organ in the inner ear responsible for hearing. C: Ear canal is the tube that connects the outer ear to the eardrum. D: Organ of Corti is a structure in the cochlea that contains sensory cells responsible for hearing.