Inheritance Flashcards
What is genotype?
Genetic makeup of individual
What is phenotype?
Visible characteristics of an individual
by proteins in the cytoplasm
What influences phenotype?
Genotype
What are the influences of both genotype and phenotype?
Environment
- radiation
- diet
How does radiation affect genotype?
Causes mutations
How many copies does each individual have of a gene?
Two copies
How many alleles does each individual have of a gene?
One alleles, both the same
or
two different alleles
How many alleles are there in a population?
Many different alleles
What does homozygous mean?
Two alleles of a gene are the same
What does heterozygous mean?
Two alleles of a gene are different
What does hemizygous mean?
Have only one allele of a gene
What are some examples of genes for which a male is hemizygous?
Genes on X chromosomes
What does dominant mean?
Allele that expresses itself regardless of other allele
What does recessive mean?
Allele that expresses itself only when it is present in both copies of gene
What does co-dominant mean?
Two different alleles are equally as dominant, expressed equally in phenotype
What is a classic example of a human co-dominant gene?
Human isoglutamin gene
What does the human isoglutamin gene code for?
Glycoproteins on surface of red blood cells
What are the three alleles of the human isoglutamin gene?
A
B
O
How are the alleles of the human isoglutamin gene expressed?
A and B are co-dominant
A is dominant over O
B is dominant over O
What are the different phenotypes of the human isoglutamin gene?
Blood group A
Blood group B
Blood group AB
Blood group O
What are the possible genotypes of blood group A phenotype?
A A
A O
What are the possible genotypes of blood group B phenotype?
B B
B O