1. Humans feel hungry when their empty stomachs contract and when glucose levels in the blood drop. Both of these situations stimulate neurons that send
messages to the brain which are interpreted as hunger. What body systems are
involved in this process as described and how?

Astudent conducts an experiment to determine how the amount of water given to a plant affects it growth what is the dependent variable for this experiment

Hormones are chemical molecules produced by endocrine glands. one such endocrine gland is the thyroid gland, which synthesizes the thyroid hormone, which in turn affects the heart muscles. which two statements describe the probable reason for the function of the hormone? the cells in the heart have specific receptors that allow for the intake of hormones. the heart and the endocrine glands have the exact same types of cells. all cells make the same types of hormones. thyroid hormones show their effect on the heart by means of specialized cells. thyroid cells and cardiac cells have different dna.

Which of the following is true of metabolism in its entirety in all organisms? a) metabolism depends on a constant supply of energy from food. b) metabolism uses all of an organism's resources. c) metabolism consists of all the energy transformation reactions in an organism. d) metabolism manages the increase of entropy in an organism.