Coat color in one breed of mice is controlled by
incompletelydominant alleles so that yellow and white are
homozygous whilecream is heterozygous. the cross of two cream
individuals willproduce.
a. all cream offspring
b. equal numbers of white and yellow mice, but no
creamoffspring
c. equal numbers of white and cream mice
d. equal numbers of yellow and cream mice
e. equal numbers of white and yellow mice, with twice as
manycreams as the other two colors.

e. equal numbers of white and yellow mice, with twice as  many creams as the other two colors.

Explanation:

According to the given information, the heterozygous genotype for the coat color gene in a mice breed has a cream-colored skin coat. Let's assume that the coat color gene has two alleles. The allele "Y" gives a yellow coat in homozygous genotype while the allele "W" gives a white coat in the homozygous genotype. The genotype of cream-colored mice is "YW". A cross between two mice each with "YW" genotype would produce the progeny in following ratio=

YW x YW= 1/4 YY: 1/2 YW: 1/4 WW

Therefore, the cross would produce equal numbers of white and yellow mice, with twice as many creams as the other two colors.

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.