Identify the glands associated with these hormones: gonadotropins, aldosterone, and epinephrine.

Correct Answer: D

Rationale: The correct answer is D because gonadotropins are secreted by the anterior pituitary gland, aldosterone is produced by the adrenal cortex, and epinephrine is released by the adrenal medulla. The anterior pituitary gland secretes gonadotropins such as FSH and LH. The adrenal cortex synthesizes aldosterone, which regulates sodium and potassium balance. The adrenal medulla produces epinephrine, involved in the fight or flight response. Choices A and C are incorrect because they do not match the correct associations of the hormones with their respective glands. Choice B is incorrect as the adrenal cortex and adrenal medulla are not part of the anterior pituitary gland.

Correct Answer: A

Rationale: The correct answer is A: Negative feedback mechanism. This is because most hormones in the endocrine system are regulated by a negative feedback loop, where the release of a hormone is inhibited once a certain level of that hormone is reached in the body. This helps maintain homeostasis. Incorrect choices: B: Positive feedback mechanism - This is less common in hormone regulation as it leads to amplification of a response rather than maintaining balance. C: Hormone-receptor complex - While hormones bind to receptors to exert their effects, this is not the primary mechanism of hormone regulation. D: Hormone-gene complex - While hormones can affect gene expression, this is not the primary mechanism of hormone regulation in the endocrine system.

Correct Answer: D

Rationale: The correct answer is D: Nervous system. The nervous system works closely with the endocrine system to regulate and coordinate the body's functions through the release of neurotransmitters and hormones. The nervous system controls rapid responses, while the endocrine system controls slower, long-term processes. The cardiovascular system (A) primarily transports blood and nutrients, the respiratory system (B) is involved in gas exchange, and the reproductive system (C) is responsible for reproduction, none of which directly coordinate with the endocrine system.

Correct Answer: B

Rationale: The correct answer is B: Insulin. Insulin is a protein hormone produced by the pancreas that regulates blood sugar levels. Proteins are large molecules made up of amino acids, and insulin fits this definition. Oxytocin (A) is a peptide hormone, not a protein. TSH (C) and ADH (D) are both peptide hormones as well, not proteins. In summary, insulin is the only option that fits the criteria of being a protein hormone.

Correct Answer: C

Rationale: The correct answer is C: Parthormone. The anterior pituitary gland secretes hormones such as Growth hormone, Follicle stimulating hormone, and Thyroid stimulating hormone, but not Parthormone. Parthormone is actually produced by the parathyroid glands, not the anterior pituitary gland. Parathormone plays a key role in regulating calcium levels in the blood. Therefore, choice C is incorrect as it does not belong to the hormones secreted by the anterior pituitary gland.