Consider two imaginary genes, a “finger number gene” and a “hand size gene”, in
ID: 66042 • Letter: C
Question
Consider two imaginary genes, a “finger number gene” and a “hand size gene”, in an imaginary population of aliens. Since we’re imagining things, let’s also imagine that the aliens have diploid genomes and life cycles just like human beings. Each gene has two possible alleles. For the finger number gene, "N" is the dominant allele for having 4 fingers on each hand, and "n" is the recessive allele for having 5 fingers on each hand. For the hand size gene, "H" is the dominant allele for having small hands, and "h" is the recessive allele for having large hands. Neither gene is on a sex chromosome.
You observe a "parental" generation cross: NNHH x nnhh. The offspring of that cross are called the "F1" generation.
Suppose that F1 individuals are crossed with the genotype nnhh (i.e., a "testcross"). If the two genes are on different chromosomes, what should you observe in the offspring of this last cross?
Question 25 options:
All offspring will have four fingers and small hands
All offspring will have five fingers and large hands
Most offspring will have four fingers on large hands, or five fingers on small hands
All combinations of hand size and finger number will be equally likely in the offspring
Most offspring will have four fingers on small hands, or five fingers on large hands
All offspring will have four fingers and small hands
All offspring will have five fingers and large hands
Most offspring will have four fingers on large hands, or five fingers on small hands
All combinations of hand size and finger number will be equally likely in the offspring
Most offspring will have four fingers on small hands, or five fingers on large hands
Explanation / Answer
The answer is
All combinations of hand size and finger number will be equally likely in the offspring
If these chromosomes are not linked, then the ratio of all the phenotypes would be 1:1:1:1