Which functional group is responsible for the sour taste of citrus fruits?

What do transitional fossils best support?

In guinea pigs, black fur (b) is dominant over white fur (b). cross a heterozygous (hybrid) black guinea pig with a homozygous (purebred) white guinea pig. complete a punnett square, identify the genotype(s), phenotype(s), and probability (% and fraction) that the offspring will be black and white?

What determines whether a particular cell is able to respond to a hormone?