Which describes a promoter? the first part of an operon that regulates where, when, and to what level a gene is expressed
the part of an operon that, if attached by a repressor protein, suppresses the expression of a gene
a cluster of genes that are expressed or repressed as a group
an enzyme that helps DNA unzip prior to transcription

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?

What element is able to combine with itself and hydrogen to form large molecules ?

Which of the following observations darwin shape his concept of descent with modification? a) species diversity declines farther from the equator. b) fewer species live on islands than on the nearest continents. c) birds can be found on islands located farther from the mainland than the birdsê¹ maximum nonstop flightdistance. d) south american temperate plants are more similar to the tropical plants of south america than to thetemperate plants of europe. e) earthquakes reshape life by causing mass extinctions.