Correct Answer: B

Rationale: The transport of oxygen in the blood is carried out by hemoglobin, which does not require calcium; instead, calcium is essential for blood clotting, muscle contraction, and nerve transmission.

Correct Answer: C

Rationale: Zinc plays a critical role in wound healing due to its involvement in cell proliferation, immune function, and protein synthesis, all of which are essential for tissue repair.

Correct Answer: A

Rationale: The correct answer is A: Streptococcus mutans and Lactobacillus species. These bacteria are primarily responsible for initiating dental caries by fermenting carbohydrates and producing acids that demineralize enamel. Choice B, Salmonella and Listeria species, are not the primary bacteria involved in dental caries. Choice C includes Salmonella which is not a primary culprit in dental caries. Choice D lists Listeria, Botulinum species, and Escherichia coli, none of which are the primary bacteria associated with initiating dental caries.

Correct Answer: D

Rationale: Secretin stimulates the pancreas to release bicarbonate ions to neutralize stomach acid and digestive enzymes into the small intestine.

Correct Answer: B

Rationale: Digestible carbohydrates are absorbed as monosaccharides (simple sugars) like glucose, which the liver can release into the bloodstream for energy.