Biology- Patterns Of Inheritance Flashcards
1
Q
What is an allele
A
A different form of a gene
2
Q
What is a genotype
A
The combination of alleles present in a gene
3
Q
What is a phenotype
A
How the alleles are expressed (physical characteristics)
4
Q
What are the two types of allele
A
Dominant and recessive
5
Q
How is dominant represented
A
Capital letters
Eg ) BB
6
Q
How is recessive shown
A
lowercase letters
Eg) bb
7
Q
What is the difference between homozygous and heterozygous
A
Homozygous is when two of the same alleles are present eg) BB
Heterozygous is when the two alleles are different eg) Bb
8
Q
What is polydactyly caused by
A
- its caused by a dominant allele
- only one allele is needed for the phenotype
9
Q
What is cystic fibrosis caused by
A
- it is caused by a recessive allele
- both copies of the recessive allele are needed
10
Q
What are the sex chromosomes in females
A
- 2 identical X chromosomes
- (XX)
11
Q
What are the sex chromosomes in males
A
- males inherit an X chromosome and a much shorter Y chromosome
- (XY)
