HESI A2 Anatomy and Physiology 2023

Correct Answer: B

Rationale: The correct answer is B: Amygdala. The amygdala is a key structure in the brain responsible for processing emotions, particularly fear and pleasure. It plays a crucial role in emotional responses and memory formation related to emotions. The frontal lobe (choice A) is primarily involved in decision-making and reasoning. The parietal lobe (choice C) is responsible for sensory processing and spatial awareness. The occipital lobe (choice D) is mainly involved in visual processing. Therefore, the amygdala is the correct choice for processing emotions due to its specific functions related to emotional responses.

Correct Answer: B

Rationale: The correct answer is B: Hinge joint. The knee joint is classified as a hinge joint because it primarily allows movement in one plane, similar to a door hinge. This type of joint permits flexion and extension movements, which are the main actions of the knee. The other choices are incorrect because: A: Ball and socket joint allows for multi-directional movement, such as the hip joint. C: Pivot joint allows for rotation around an axis, like the joint between the radius and ulna bones in the forearm. D: Saddle joint allows for movements in two planes, like the joint at the base of the thumb.

Correct Answer: A

Rationale: Insulin is the correct answer because it is secreted by the pancreas in response to high blood glucose levels. Insulin helps to lower blood glucose levels by promoting the uptake of glucose into cells for energy storage. Glucagon, on the other hand, is secreted by the pancreas to increase blood glucose levels. Somatostatin regulates the release of insulin and glucagon but does not directly lower blood glucose levels. Cortisol is a stress hormone secreted by the adrenal glands and does not play a direct role in lowering blood glucose levels.

Correct Answer: B

Rationale: The correct answer is B: Thyroxine. Thyroxine, produced by the thyroid gland, plays a key role in regulating metabolism by controlling the body's metabolic rate. It influences how fast or slow our cells use energy. Insulin (A) regulates blood sugar levels, not metabolism. Glucagon (C) raises blood sugar levels. Cortisol (D) is a stress hormone that affects various body functions but is not primarily responsible for regulating metabolism. Thyroxine is crucial for maintaining overall metabolic balance 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.