Which statements help explain the scientist's conclusions? Select all of the answers that apply.
A. All 8 species of modern bears have the same adaptations.
B. The same ancestral bear species can give rise to two or more species of modern bears.
C. Each of the 8 species of modern bears may have high fitness in only some environments.
D. All of the 8 species of modern bears have equally high fitness in any environment where bears live.
E. One of the species of modern bears was the ancestor of all the other bear species.

Which best describes a benefit of using dna technology in medicine? a) medicine can be produced in mass quantities. b) medicine can be distributed at a reduced cost. c) medicines have fewer side effects. d) medicines are resistant to antibiotics.

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.

Can a trait be both polygenic and have multiple alleles? explain why or why not.