four variables that are most important to control in an experiment about the rate at which bread turns moldy.

an organism's phenotype is the  form of a trait  that it  displays. for  flowercolor, a pea  plant  can  display  a phenotype of purple or white flowers. an organism's  genotype  is the alleles of a gene it contains. based on his data, mendel concluded that a phenotype can be  determined  by more than one  genotype.

a lot of people sadly don't know the best way to learn is cheating off of your friends or this amazing thing called google

the answer is d p: cell, q: organ, r: organ system, s: tissue