B6- More Genetic Diagrams Flashcards
What is the outcome of crossing a homozygous dominant hamster (BB) with a homozygous recessive hamster (bb)?
All offspring are normal (boring)
In this genetic scenario, the dominant trait overshadows the recessive trait.
What is the result of crossing a homozygous dominant hamster (BB) with a heterozygous hamster (Bb)?
All offspring are normal (boring)
The homozygous dominant trait results in normal offspring regardless of the heterozygous parent.
What ratio indicates that the original cross involved a homozygous dominant (BB) and a homozygous recessive (bb) hamster?
3:1 ratio
This ratio suggests the presence of both dominant and recessive alleles in the offspring.
What is the dominant allele for long hair in cats represented by?
‘H’
The recessive allele for short hair is represented by ‘h’.
What ratio of kittens would you expect when crossing a heterozygous long-haired cat (Hh) with a homozygous recessive short-haired cat (hh)?
1:1 ratio
This ratio indicates equal probability of long-haired and short-haired offspring.
In a family tree for cystic fibrosis, how can you determine that the allele for cystic fibrosis is not dominant?
Many family members carry the allele but do not have the disorder
This indicates that the allele is recessive, as it does not manifest in the phenotype of carriers.
What is the probability that a new baby from two cystic fibrosis carriers will have the disorder?
25% chance
The potential offspring could be affected, carriers, or unaffected.
What are the possible genotypes for a baby from two cystic fibrosis carriers?
- Unaffected (FF)
- Carrier (Ff)
- Have cystic fibrosis (ff)
This illustrates the inheritance patterns of a recessive genetic disorder.
Fill in the blank: The allele for cystic fibrosis is represented by _______.
f
The dominant allele for normal function is represented by ‘F’.
