Dihybrid Inheritance Flashcards
1
Q
Define dihybrid inheritance.
A
The simultaneous inheritance of two unlinked genes I.e genes on different chromosomes.
2
Q
How did Mendel investigate dihybrid inheritance?
A
He knew that with pea seeds, yellow was dominant over green and round was dominant over wrinkled. He crossed plants with two pairs of contrasting characteristics.
3
Q
When the parental genotypes are dominant and recessive, how many alleles can be made?
A
1 for each. For example: RRYY = RY. rryy = ry.
4
Q
When the parental genotype is heterozygous, how many alleles can be made?
A
- RrYy = RY, Ry, rY, ry.
5
Q
What are Mendelian ratios expected from a dihybrid cross of two heterozygotes?
A
9:3:3:1
6
Q
How can you do a test cross for dihybrid inheritance?
A
Cross it with a homozygous recessive.
