Final answer:
The correct answer to this question is C) Decrease in hormone levels. After hypophysectomy, there is a decline in the production of pituitary hormones, which affects the stimulation of other endocrine glands and leads to decreased hormone levels throughout the body.
Step-by-step explanation:
If an animal has been hypophysectomized, this means that its pituitary gland has been removed or destroyed. As a result, you would expect a decrease in hormone levels, because the pituitary gland produces critical hormones that stimulate other glands to release hormones. This would lead to a decrease in hormones such as thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), luteinizing hormone (LH), and follicle-stimulating hormone (FSH), which in turn would lead to reduced hormone production in other endocrine organs such as the thyroid gland, adrenal glands, and gonads. The correct answer is C) Decrease in hormone levels.
Consider the feedback mechanism where increasing levels of certain hormones, such as testosterone, inhibit the production of GnRH, LH, and FSH by the hypothalamus and pituitary. With the pituitary gland not functioning (hypophysectomized), this inhibitory feedback loop is disrupted, which further contributes to the hormone imbalance.