microbiology an introduction test bank

Correct Answer: B

Rationale: The primary function of bacterial capsules is to aid in adhesion and protect against phagocytosis. Capsules help bacteria adhere to surfaces and evade immune system detection by preventing phagocytosis. This is important for bacterial survival and colonization in host organisms. Choice A, protein synthesis, is incorrect as capsules do not directly participate in this process. Choice C, facilitate motility, is incorrect as capsules are not involved in bacterial movement. Choice D, synthesize DNA, is incorrect as capsules do not have a role in DNA synthesis. Thus, the correct answer is B.

Correct Answer: A

Rationale: The correct answer is A: Oxidation. Phase I reactions in biotransformation involve introducing or unmasking functional groups through oxidation, reduction, or hydrolysis. Oxidation reactions typically involve the addition of an oxygen atom or removal of hydrogen atoms, making them common phase I reactions. In this process, enzymes like cytochrome P450 play a crucial role in catalyzing the oxidation reactions. Conjugation (B), acetylation (C), and glucuronidation (D) are all examples of phase II reactions, which involve the conjugation of the drug or metabolite with endogenous compounds to increase water solubility for excretion. These reactions typically follow phase I reactions and are not classified as phase I reactions in biotransformation.

Correct Answer: D

Rationale: The correct answer is D, Shiga anatoxin. This is because the Salk and Sabin vaccines are actually for polio, not chemical vaccines. HPV vaccine is a biological vaccine, not a chemical one. Shiga anatoxin is a chemical vaccine used against Shigella bacteria, making it the only correct choice for chemical vaccines in this question.

Correct Answer: A

Rationale: The correct answer is A: cryophiles. Psychrophiles are microorganisms that thrive in cold temperatures. The prefix "cryo-" means cold, which accurately describes the environment in which these organisms grow. Choice B, thermophiles, are organisms that thrive in high temperatures. Choice C, mesophiles, grow best at moderate temperatures. Choice D, psychrotrophs, are organisms that can grow at refrigeration temperatures but have an optimal growth temperature range different from psychrophiles.

Correct Answer: A

Rationale: Rationale: The correct answer is A: Trichomonas vaginalis. 1. Symptoms of urogenital inflammation match Trichomonas vaginalis infection. 2. Description matches Trichomonas vaginalis characteristics: pear-shaped, pointed spike, big nucleus, undulating membrane. 3. Trichomonas hominis and buccalis do not typically infect urogenital tracts. 4. Trypanosoma gambiense causes African trypanosomiasis, not urogenital infections.