Which of the following best summarizes how hormone levels are controlled? A: Hormones are controlled by a feedback loop; information about a system is sent back to the controller of the system to improve its function. B: Hormones are controlled by oxygen levels; the internal environment maintains all systems, including endocrine functions. C: Hormones are controlled by muscles; hormones are released when muscles contract and stopped when muscles relax. D: Hormones are controlled by the nervous system; the spinal cord sends messages about hormone levels to the brain.

Insulin causes blood glucose levels to drop, which signals the pancreas to stop producing insulin in a negative feedback loop.Hormonal stimuli refer to the release of a hormone in response to another hormone. ... The anterior pituitary in turn releases hormones that regulate hormone production by other endocrine glands.

i think A

Explanation:

answer: after carbon dioxide enters the leaf through stomata it moves into the mesophyll cells where photosynthesis occurs and glucose is constructed. respiration occurs when glucose (sugar produced during photosynthesis) combines with oxygen to produce useable cellular energy.

explanation:

what in the weirdo : o