Question

11 multiple choice 1 point
based on the parent genotypes shown what are the probabilities of each blood phenotype, written as a ratio?
parent 1 genotype: $i^b i$
parent 2 genotype: $i^a i^a$
1 type a: 1 type b: 1 type o: 1 type ab
1 type a: 0 type b: 2 type o: 1 type ab
1 type a: 0 type b: 0 type o: 1 type ab
1 type a: 0 type b: 0 type o: 0 type ab
12 multiple choice 1 point
in some cattle the genes for brown hair and for white hair are codominant. cattle with alleles for both brown and white hair, have both brown and white hairs. this condition gives the cattle a reddish color, and is referred to as roan. what is the probability, expressed as a fraction, of a red cow and a white bull having a roan offspring?

Explanation:

For Question 11:

Step1: Identify parent gametes

Parent 1 ($I^B i$) produces gametes: $I^B$, $i$; Parent 2 ($I^A I^A$) produces gametes: $I^A$, $I^A$

Step2: Perform Punnett square

	$I^B$	$i$
$I^A$	$I^A I^B$	$I^A i$

Step3: Assign phenotypes

$I^A I^B$ = Type AB; $I^A i$ = Type A. Count: 2 Type A, 2 Type AB → simplify ratio to 1:0:0:1

Step1: Define genotypes

Let $B$ = brown allele, $W$ = white allele. Red cow = $BB$, white bull = $WW$

Step2: Identify parent gametes

Red cow produces $B$ gametes; white bull produces $W$ gametes

Step3: Cross gametes

All offspring inherit $B$ and $W$, so genotype $BW$ (Roan)

Step4: Calculate probability

All 4/4 offspring are Roan, simplified to $\frac{1}{1}$

Answer:

1 Type A : 0 Type B : 0 Type O : 1 Type AB

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For Question 12: