Correct Answer: B

Rationale: The correct function associated with the dermal layer of the skin is to provide support and structure to the skin. The dermis is the thickest layer of the skin and is responsible for maintaining the skin's integrity and firmness. Choices A, C, and D are incorrect as sensory perception, protection from UV rays, and insulation are functions associated with other layers of the skin, such as the epidermis and subcutaneous tissue.

Correct Answer: B

Rationale: The correct answer is the tricuspid valve. The tricuspid valve is located between the right atrium and the right ventricle of the heart. Its main function is to prevent the backflow of blood from the right ventricle into the right atrium during the heart's pumping cycle. Choice A, the aortic valve, is responsible for preventing backflow from the aorta into the left ventricle. Choice C, the pulmonic valve, prevents backflow from the pulmonary artery into the right ventricle. Choice D, the mitral valve, prevents backflow from the left ventricle into the left atrium.

Correct Answer: A

Rationale: The correct answer is 'Hematocrit.' Hematocrit is the measurement of the percentage of red blood cells in whole blood. It is used to diagnose conditions such as anemia and dehydration. Choice B, 'Hemoglobin,' measures the amount of hemoglobin in the blood, not the percentage of red blood cells. Choice C, 'Mean corpuscular volume,' measures the average volume of a red blood cell, not the percentage of red blood cells. Choice D, 'Reticulocyte count,' measures the percentage of young red blood cells in the blood, not the percentage of red blood cells.

Correct Answer: C

Rationale: The correct answer is C: Store and concentrate bile, a fluid produced by the liver that helps with fat digestion. The gallbladder stores bile produced by the liver and releases it to aid in the digestion of fats. Choice A is incorrect as the liver, not the gallbladder, filters blood and detoxifies harmful substances. Choice B is incorrect because the production of enzymes primarily occurs in the pancreas, not the gallbladder. Choice D is incorrect as the gallbladder's main role is not to further digest food but to store and release bile.

Correct Answer: A

Rationale: The correct answer is the Distal convoluted tubule (DCT). The DCT is the part of the nephron closest to the collecting duct, where the final adjustments to electrolyte and fluid balance are made. Bowman's Capsule is located at the beginning of the nephron, where filtration of blood occurs. The Afferent Arteriole brings blood to the glomerulus for filtration. The Proximal Convoluted Tubule (PCT) is situated after the Bowman's Capsule and is not the part closest to the collecting duct.