When blood calcium levels are high, ____ is released from the thyroid gland to deposit the excess calcium into the bones.

Correct Answer: B

Rationale: Calcitonin is the correct answer because it is released from the thyroid gland in response to high blood calcium levels to deposit the excess calcium into the bones, decreasing blood calcium levels. Parathyroid hormone (A) works in the opposite way, increasing blood calcium levels by releasing calcium from bones. Oxytocin (C) is a hormone involved in labor and breastfeeding, not calcium regulation. Glucagon (D) is released from the pancreas to increase blood glucose levels, not calcium levels. Therefore, calcitonin is the most suitable choice for regulating high blood calcium levels by promoting calcium deposition in the bones.

Correct Answer: C

Rationale: The correct answer is C: Gluconeogenesis is not a function of insulin. Insulin's main role is to lower blood glucose levels by promoting glucose uptake and storage. Gluconeogenesis is the process of synthesizing glucose from non-carbohydrate sources, such as amino acids and glycerol, to increase blood glucose levels. Insulin inhibits gluconeogenesis by suppressing the enzymes involved in this process. Choices A, B, and D are all functions of insulin: A) Decreasing glycogenolysis - insulin promotes glycogen synthesis by inhibiting glycogen breakdown, B) Lipogenesis - insulin enhances the conversion of excess glucose into fatty acids for storage, and D) Glycogenesis - insulin increases the formation of glycogen from glucose for storage.

Correct Answer: A

Rationale: Aldosterone is the correct answer as it specifically regulates blood sodium and potassium levels by acting on the kidneys to enhance sodium reabsorption and potassium excretion. Cortisol is a stress hormone, not directly involved in electrolyte regulation. Glycogens are stored glucose molecules, not hormones. Pheromones are chemical signals for communication, not involved in electrolyte balance.

Correct Answer: C

Rationale: The correct answer is C because lipid-soluble hormones can freely diffuse through cell membranes to interact with intracellular receptors, leading to changes in gene expression. This mechanism is characteristic of lipid-soluble hormones, such as steroid hormones. Choice A is incorrect because lipid-soluble hormones are not constantly produced in the anterior pituitary gland. Choice B is incorrect as lipid-soluble hormones are hydrophobic, not hydrophilic, and are often transported bound to carrier proteins in the blood. Choice D is incorrect because lipid-soluble hormones are not formed from amino acids; rather, they are derived from cholesterol or similar compounds.

Correct Answer: D

Rationale: The correct answer is D, submandibular glands, as they produce the majority of salivary volume. These glands are the largest of the major salivary glands and secrete saliva rich in enzymes and mucin, contributing significantly to the total saliva volume. The lingual glands (A) are minor salivary glands located in the tongue and contribute a small portion of saliva. The sublingual glands (B) are also minor salivary glands located beneath the tongue, producing a smaller volume compared to the submandibular glands. The parotid glands (C) are another major salivary gland, but they produce a lesser volume of saliva compared to the submandibular glands.