Question

In fruit flies, the allele for white eyes is recessive to the allele for red eyes. In a generation of fruit flies, 45 males with white eyes, 46 females with white eyes, 44 males with red eyes, and 47 females with red eyes are produced. Which of the following is the best conclusion you can make about the parents of this generation?

Select one:
a. One parent was heterozygous for eye color and the other was homozygous with red eyes.
b. Both parents were homozygous with red eyes.
c. One parent had white eyes and the other was heterozygous for eye color.
d. Both parents were heterozygous for eye color.


While mRNA strands are being created, a sequence is sometimes miscopied. What is the worst that could happen to a cell should this take place?

a. The cell will not make functional proteins from that mRNA strand.
b. The cell will die once it tries to use that strand of mRNA.
c. The cell will have to destroy any ribosomes that use the mRNA strand.
d. The cell will pass the mRNA on to all the cells made from it.


Which of the following would most likely cause a harmful genetic mutation?

a. Insertion of three base pairs into the genetic sequence.
b. Polyploidy mutations, or inheriting an extra set of chromosomes.
c. Chromosomal mutation in germ-line cells are inherited.
d. Exposure to other mutated organisms or cells.


Can someone help me out with these??? The incorrect answers are 1-A
2- D 3-A

Answer 1

1 is C - see first attachment. Genotypes with Y's represent males, and big R represents red eyes, while little r represents white eyes. For example XRxr is a heterozygous (red-eyed) female, and XrYr is a homozygous white-eyed male.

2 is B because the absence of functional proteins and some ribosomes due to the mRNA strand is not as detrimental as the loss of the entire cell.

3 is B. (The insertion of 3 base pairs into a genetic sequence is the length of a single codon, meaning that only one amino acid in the entire polypeptide was added)