Bacteria that have been identified as frequently responsible for nonsexually transmitted infections of the reproductive system include:

Correct Answer: A

Rationale: The correct answer is A (Escherichia coli, Gardnerella vaginalis, and Staphylococcus aureus) because they are known to commonly cause nonsexually transmitted infections of the reproductive system. Escherichia coli can cause urinary tract infections that can ascend to the reproductive system. Gardnerella vaginalis is associated with bacterial vaginosis, a common infection of the vagina. Staphylococcus aureus can cause infections in the reproductive system through various means. Choices B, C, and D are incorrect: B: Streptococcus faecalis, Klebsiella oxytoca, and Serratia marcescens are not commonly associated with reproductive system infections. C: Clostridium tetani and Bacillus cereus are not typically involved in reproductive system infections. D: Neisseria gonorrhoeae causes sexually transmitted infections, Helicobacter pylori causes gastrointestinal issues, and Pseudomonas aeruginosa is more

Correct Answer: C

Rationale: The correct answer is C: E + S = P. This notation represents the interaction between an enzyme (E) and a substrate (S) resulting in a product (P). Enzymes facilitate chemical reactions by binding to substrates and converting them into products. Choice A is incorrect because it does not include the enzyme in the reaction. Choice B is incorrect as it involves two substrates binding to the enzyme, not a substrate converting to a product. Choice D is incorrect as it shows two substrates reacting to form a product without involvement of an enzyme. Thus, choice C accurately represents the process of enzymatic reactions involving enzymes, substrates, and products.

Correct Answer: D

Rationale: The correct answer is D: complex. Bacteriophages are considered complex viruses because they have a complex structure consisting of a polyhedral head, a helical tail, and tail fibers. The head contains the viral genetic material, while the tail facilitates attachment to the host bacterial cell. This complexity distinguishes bacteriophages from simpler viruses like helical and icosahedral viruses. Helical viruses have a rod-like shape, while icosahedral viruses have a symmetrical, 20-sided structure. Enveloped viruses have a lipid bilayer envelope surrounding their capsid, which bacteriophages lack. Therefore, the unique and intricate structure of bacteriophages classifies them as complex viruses.

Correct Answer: A

Rationale: The correct answer is A: ethylene oxide. Ethylene oxide is a toxic, odorless gas commonly used as a sterilizing agent in healthcare settings due to its ability to effectively kill bacteria, viruses, and fungi. It is a highly reactive compound that can penetrate porous materials, making it an ideal choice for sterilization purposes. Incorrect choices: B: Carbon dioxide is not used as a sterilizing agent and is not toxic. C: Carbon monoxide is not commonly used for sterilization and has a distinct odor. D: Propane is not used for sterilization in healthcare settings and is not odorless.

Correct Answer: A

Rationale: The correct answer is A: Acid resistance. Tuberculous bacilli are acid-fast bacilli, meaning they resist decolorization by acid-alcohol after staining with Ziehl-Neelsen stain. This property is due to the high lipid content in the cell wall of Mycobacterium tuberculosis. Alkali resistance (B) and alcohol resistance (C) are not specific properties of tuberculous bacilli. Capsule formation (D) is a characteristic of some bacteria but is not a defining feature of tuberculous bacilli.