What will lead to changes in a phenotype of an individual? a. medicines
b. nutrition frequency
c. DNA sequence variation
d. all of the above

Why is it important to reduce the number of chromosomes in half when forming gametes for sexual reproduction?

Explain how ancient whale fossils found in eqypt are believed to support the theory of evolution.

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.