Quizlet HESI A2 Anatomy and Physiology

Correct Answer: B

Rationale: Platelets play a crucial role in blood clotting. When a blood vessel is damaged, platelets adhere to the site to form a plug to stop bleeding. This process is essential for wound healing and preventing excessive blood loss. Platelets do not transport oxygen (A), fight infection (C), or transport nutrients (D). Oxygen is carried by red blood cells, immune cells fight infection, and nutrients are transported by plasma and other blood components.

Correct Answer: B

Rationale: The correct answer is B: Absorbing nutrients. The small intestine is where the majority of nutrient absorption occurs in the digestive system. Its long and highly folded structure provides a large surface area for nutrients to be absorbed into the bloodstream. This process is essential for the body to obtain the necessary vitamins, minerals, proteins, and other nutrients from food. Breaking down fats (choice A) primarily occurs in the small intestine but is not its primary function. Secreting digestive enzymes (choice C) is the role of the pancreas and liver, while storing bile (choice D) is the function of the gallbladder.

Correct Answer: B

Rationale: The correct answer is B: To exchange gases. Alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide takes place. Oxygen from the air we breathe enters the blood through the alveoli, and carbon dioxide is removed from the blood and exhaled. This process is essential for respiration. Explanation of other choices: A: To filter blood - This is incorrect because the alveoli do not filter blood. Filtering of blood primarily occurs in the kidneys and liver. C: To transport nutrients - This is incorrect because the alveoli are not involved in transporting nutrients. Nutrient transport mainly occurs through the bloodstream. D: To store oxygen - This is incorrect because the alveoli do not store oxygen. Oxygen is temporarily stored in the red blood cells and muscle tissues.

Correct Answer: B

Rationale: The correct answer is B: Heart. The heart is not a component of the central nervous system (CNS) as it is part of the cardiovascular system. The CNS consists of the brain, spinal cord, and retina. The brain controls cognitive functions, the spinal cord transmits nerve signals, and the retina is a part of the visual system. Choice B is incorrect as the heart's function is to pump blood and is not involved in CNS functions.

Correct Answer: B

Rationale: The correct answer is B: To absorb nutrients. The small intestine plays a crucial role in absorbing nutrients from digested food. It is lined with villi that increase the surface area for nutrient absorption. Other choices are incorrect as the small intestine does not store bile (A), its main role is not to digest food as that is primarily done in the stomach (C), and while it does produce some enzymes, its primary function is not enzyme production (D).