Inheritance, and The HGP Flashcards
What is meant by allele?
Different forms of a gene.
What is meant by dominant?
Only one out of 2 needs to be expressed.
What is meant by recessive?
Both have to be expressed.
What is meant by homozygous?
Both inherited alleles are the same.
What is meant by heterozygous?
1 of inherited is dominant, and other is recessive.
What is meant by genotype?
Combination of alleles.
What is phenotype?
Physical characteristics that are observed.
What is codominance?
Some alleles are both expressed in the same phenotype.
What is an example of codominance?
ABO blood group, alleles of A, B and O can be expressed at same locus.
a and o?
A
A and B
AB
a and a
a
b and b
b
o and o
o
why is o rare?
As it requires both alleles to be dominant.
What is a sex linked genetic disorder?
When an allele is not found on chromosomes, instead on sex chromosomes. These can be recessive or dominant. These are common in males, as females have a spare chromosome, reducing effect.
Why is human genome project important?
Prediction and prevention of diseases, testing and treatment for inherited disorders, and new better medicine, as there are over 20000 genes mapped.
