Alleles are: A)different genes
B)building blocks of DNA
C)proteins
D)alternate forms of a gene

Awater molecule is polar because there is an uneven distribution of these between the oxygen and hydrogen atoms.

Which of the following is an example of a tissue on the digestive system a.the stomach b.smooth muscle that lines the stomach c.nerve cells in the stomach d. enzyme molecules in the stomach

8) animals respond in various ways to stimuli detected through their senses. some of these responses are stimulated by the presence of danger. which of these animal responses is the best example of a response to an immediate threat? a) a rooster crows every morning at the first sign of light. b) as something approaches an octopus, it shoots a cloud of ink. c) from late fall until spring, bears hibernate to preserve energy. d) a dog is getting hot in the sunlight, so he moves to a shaded area.