Question

In Drosophilia, the gene for red eyes, R, is dominant for the gene for white eyes, r. This is sex-linked Determine the possible genotype and phenotype ratios expected from a cross between, (a) heterozygous female and red-eyed male, (b) a heterozygous female and a white-eyed male, (c) a homozygous dominate female and a redeyed male, and (d) a homozygous dominate female with a white-eyed male.

Answer 1

Let XR stand red-eyed gene and Xr for white.

Heterozygous female would be XR Xr, and red-eyed male would be XR Y. Do the Punnett square with these genes.

Use the same method for the other combinations.

I hope this helps. Thanks for asking.

Answer 2

Convert the following DNA sequence into its RNA equivalent and then using the genetic code, convert that RNA sequence into the amino acid sequence.

5’–TACTTCTTCAAGACT-3’

For this above DNA sequence, what information is contained in the genetic code for the first and last codon?