Select the correct answer from the list.

When it is burned to produce electricity (petroleum, natural gas, coal) emits the most carbon dioxide. This fossil fuel accounted for ( 1/3, 1/2, 3/4 ) of the electricity generated in the United States and emitted 68 percent of the carbon dioxide produced by generating electricity.

Which of the following sex and generation combinations directly produces the pollen tube of angiosperms? a) male gametophyteb) female gametophytec) male sporophyted) female sporophyte

6. in domesticated cats, the following are independently assorting: normal ears (t) is dominant to tufted ears (t); curved whiskers (c) is dominant to straight whiskers (c); the presence of six toes (s) is dominant to five toes (s); gene for hair length is an x-linked codominant. the three phenotypes for hair length are long (xhxh), medium (xhxh), and short (xhxh); medium is the heterozygous condition. given two parents: ttccssxhxh x ttccssxhy how many different gametes could be formed in the female cat with respect to these four traits? how many phenotypes are possible in the offspring from this mating?

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.