Ayellow pea plant (yy) and a green pea plant (yy) could not produce green offspring. true or false?

The given statement is False.

Explanation-

Yellow pea plant is a dominant trait ( represented by Y allele) over the green pea plant ( that is represented by y allele), which is a recessive trait. Green pea plant will be produced only when both the alleles are recessive that is with the genotype yy.

As per the question, genotypes of parents are Yy and yy. When they are crossed, they will produce 50% green pea plant. Refer punnett square.

the offspring would all be white. if the parents are both white flowers then they have the genotype rr, which when crossed results in an all white punnet square.

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.