types of inheritance

Question 1

complete dominance

Answer 1

One allele is completely dominant over the other and “masks” it.
Ex: Aa (A dominates a)

Question 2

incomplete dominance

Answer 2

Two or more alleles influence the phenotypes. Often the phenotype is a blending or mixing of the other phenotypes.
Only the heterozygous is affected.
Ex: When you cross a RED flower with a WHITE flowers you get a PINK flower.

Question 3

codominance

Answer 3

Both alleles for a gene are expressed in the heterozygous individual.
Neither allele is dominant or recessive.
Alleles do not blend

Question 4

when codominance, only the…

Answer 4

heterozygous is affected
Ex: When you cross a red horse with a white horse you get a ROAN horse.

Question 5

If you encounter a problem that has three phenotypes..

Answer 5

it is either incomplete or codominance.

Question 6

if the heterozygous is a mix,

Answer 6

it is incomplete dominance.

Question 7

If the heterozygote expresses both alleles,

Answer 7

it is codominance.

Question 8

Multiple Alleles (Blood types)

Answer 8

More than two types of alleles (not just B or b). But each person gets only two alleles.
There are two alleles that are equally dominant and a recessive third allele.
Ex: Human blood type

Question 9

human blood types

Answer 9

Blood types are determined by the antigens (proteins) attached to the outside or a red blood cell.

Question 10

The three alleles in blood types are:

Answer 10

IA = Type A allele (A-antigens)
IB = Type B allele (B-antigens)
I = Type O allele (No antigens)

Question 11

the genotypes for each blood type:

Answer 11

Blood type A
IAIA or IAi
Blood type B
IBIB or IBi
Blood type AB
IAIB
Blood type O
ii