Question

Please show all work step by step. Thank you.

1)

A= pigment
a = albino

Presence of pigment is completely dominant over absence of pigment. An individual heterozygous for pigment with an AB bloodtype mates with another individual that is heterozygous for pigment and has AB bloodtype. What are the phenotypes and frequencies of the progeny?

2) Achondroplasia (dwarfism) is caused by a dominant allele. A woman and a man both with dwarfism marry (AaxAa). If individuals homozygous for achondroplasia (AA) are not viable (death of embryo), what would be the genotypes, phenotypes and phenotypic ratios expected in the progeny? What if a dwarf female (Aa) mates with a normal height male (aa)?

Answer 1

2.

	A	a
A	AA	Aa
a	Aa	aa

From the table it is visible that 2 will be Aa and one will be aa. From the question we can see that organism having AA genotype will not survive.

So, they can have kids with only two genotypes.

Aa aa

Phenotypic ratio- 2:1

Aa- dwarf

aa- normal

	a	a
A	Aa	Aa
a	aa	aa

There will be 2 possible genotypes.

Aa- Dwarf

aa- normal

phenotypic ratio- 1:1

1. AaA*B*

AA* AB* aA* aB*

A= pigment
a = albino

A* B* = AB BLOOD TYPE

GAMETES- AA* AB* aA* aB*

	AA*	AB*	aA*	aB*
AA*	AA*AA*	AA*AB*	AA*aA*	AA*aB*
AB*	AB*AA*	AB*AB*	AB*aA*	AB*aB*
aA*	aA*AA*	aA*AB*	aA*aA*	aA*aB*
aB*	aB*AA*	aB*AB*	aB*aA*	aB*aB*

AAA*A*- 1

AAA*B*- 2

AaA*A*- 2

AaA*B*- 4

AAA*B*- 1

AaB*B*-2

aaA*A*- 1

aaB*B*- 1

aaA*B*-2