A mutation A
is a person or an animal randomly selected from the population.

B
is a random change in a cell's DNA.

C
always occurs when the male's sperm joins the female's egg.

D
is produced by mating two different species.

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.

What is one reason why transpiration is important in plants? question 19 options: it produces food from the sugar in the plant cells. it enables the flow of water out of the plant. it produces carbon dioxide in the leaves of the plant.

What happens when a scientific theory is shown to be an accurate description of a phenomenon?