/gives brainliest a disease-resistant variety of a sexually reproducing crop was planted on a field with an existing nonresistant variety. after a few years, pests severely attacked the plants. the older, nonresistant plants died. however, the recently grown plants survived. why did the new plants survive? a) the pests can’t attack the new plants. b) the new plants had the resistant gene. c) the old plants were covered with low-grade insecticides. d) the new plant variety was younger than the initial plants. e) the recently grown plants had an increased life span.

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.