Why might animals have vestigial structures?

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 organ is the first to receive nutrients that have been absorbed from the digestive tract?

How do plants obtain more sunlight a.) they lean towards the light b.)they grow straight up c.) they only live in sunny areas, like the tropics d.) they stay low to the ground