Final Exam Pathophysiology

Correct Answer: B

Rationale: The correct answer is B, Hemolytic anemia. Normocytic-normochromic anemia is a type of anemia characterized by normal-sized and normal-colored red blood cells. Hemolytic anemia is a condition where red blood cells are destroyed prematurely, leading to normocytic-normochromic anemia. Sideroblastic anemia (Choice A) is characterized by ringed sideroblasts in the bone marrow. Pernicious anemia (Choice C) is due to vitamin B12 deficiency. Iron deficiency anemia (Choice D) is characterized by microcytic-hypochromic red blood cells.

Correct Answer: A

Rationale: The correct answer is A, 'Physiologic.' Physiologic atrophy is a normal part of development, like the reduction in thymus size during childhood. Pathologic atrophy (choice B) refers to tissue wasting due to disease, not a normal process like the reduction in thymus size. Disuse atrophy (choice C) results from a lack of physical activity or stimulation, which is not the case with thymus size reduction. Neurogenic atrophy (choice D) is caused by damage to or diseases of the nerves supplying the muscles, not related to the thymus size reduction seen in childhood.

Correct Answer: A

Rationale: Amphotericin B is an antifungal medication that acts by binding to ergosterol, a component of fungal cell membranes, forming pores that disrupt the integrity of the membrane. This action leads to leakage of cellular contents and ultimately cell death. Choice B is incorrect as amphotericin B does not bind to an enzyme required for the synthesis of ergosterol. Choice C is incorrect as the drug primarily affects the cell membrane rather than the cell wall. Choice D is also incorrect as amphotericin B does not inhibit glucan synthetase.

Correct Answer: B

Rationale: The correct answer is B: 'It decreases bone resorption and increases bone density.' Raloxifene, a selective estrogen receptor modulator (SERM), works by decreasing bone resorption, which is the breakdown of bone, and increasing bone density. This action helps in preventing bone loss and maintaining bone strength. Choice A is incorrect because raloxifene does not stimulate the formation of new bone but rather prevents its breakdown. Choice C is incorrect as raloxifene does not increase the excretion of calcium but rather helps in maintaining calcium levels in the bones. Choice D is also incorrect as raloxifene does not directly increase calcium absorption in the intestines.

Correct Answer: D

Rationale: The correct answer is D: Type IV hypersensitivity reactions involve cell-mediated immunity, not an antibody response. This question tests knowledge of hypersensitivity reactions and their classification. Type I hypersensitivity reactions involve IgE antibodies, Type II involves IgG or IgM antibodies, and Type III involves immune complex deposition. Type IV hypersensitivity reactions are delayed and involve T cells, not antibodies. Therefore, if a person believes that Type IV hypersensitivity reactions involve an antibody response, more teaching is required.