Question

1. for each of the following write whether it is homozygous dominant, heterozygous or homozygous recessive.

aa _____________ gg _____________
pp _____________ ii _____________
tt _____________ tt _____________
use the following information for questions 3-5:
in dogs, the gene for fur color has two alleles. the dominant allele (f) codes for grey fur and the recessive allele (f) codes for black fur.

1. the female dog is heterozygous. the male dog is homozygous recessive. figure out the percentage or ratio of possible phenotypes and genotypes of their puppies by using a punnett square.

% of possible genotypes:
ff: ________
ff: ________
ff: ________
% of possible phenotypes:
black fur: _______________
grey fur: _______________
place the alleles for the male parent below. one allele on each line:
______ ______
place the alleles for the female parent on the side. one allele on each line:
________
________

Explanation:

Step1: Classify genotype types

• AA: Two dominant alleles → homozygous dominant
• gg: Two recessive alleles → homozygous recessive
• Pp: One dominant, one recessive → heterozygous
• Ii: One dominant, one recessive → heterozygous
• tt: Two recessive alleles → homozygous recessive
• TT: Two dominant alleles → homozygous dominant

Step2: Define parent alleles for Punnett Square

Female (heterozygous): $F$, $f$
Male (homozygous recessive): $f$, $f$

Step3: Fill Punnett Square

	$f$	$f$
$f$	$ff$	$ff$

Step4: Calculate genotype percentages

Total squares = 4

• FF: 0 out of 4 → $0\%$
• Ff: 2 out of 4 → $\frac{2}{4} \times 100\% = 50\%$
• ff: 2 out of 4 → $\frac{2}{4} \times 100\% = 50\%$

Step5: Calculate phenotype percentages

• Black fur (ff): 2 out of 4 → $50\%$
• Grey fur (FF, Ff): 2 out of 4 → $50\%$

Answer:

Question 2:

AA: homozygous dominant
gg: homozygous recessive
Pp: heterozygous
Ii: heterozygous
tt: homozygous recessive
TT: homozygous dominant

Question 3:

Punnett Square:

	$f$	$f$
$f$	$ff$	$ff$

% of possible Genotypes:

FF: $0\%$
Ff: $50\%$
ff: $50\%$

% of possible Phenotypes:

Black fur: $50\%$
Grey fur: $50\%$