Human Biology (Other types of Inheritance) Flashcards
What is Co-dominance?
A situation where two or more alleles are equally dominant.
What does co-dominance mean for phenotypes of characteristics?
That if both the alleles are present, they will both be observed.
Provide 1 example of co-dominance in humans.
The B^M and B^N alleles for the M and N antigens in blood. Neither allele is dominant to the other, and so 3 phenotypes are possible.
What is a multiple allele?
When there are 3 or more alleles for a particular characteristic.
What is the position on the chromosomes of the gene in a multiple allele case, called?
Multiple allelic
Provide an example of multiple alleles in humans
The ABO blood type. A person may be A, B, AB, or O.
Blood groups are inherited, and the grouping system is based on the individual inheriting I^A I^B or I.
What is incomplete dominance?
When neither allele is completely dominant over the other, resulting in a unique heterozygous phenotype.
What is incomplete dominance with ‘ alleles for the same gene’?
Incomplete dominance occurs when an individual inherits two different alleles for the same gene.
What is incomplete dominance with ‘Intermediate Phenotype’?
Heterozygous display an intermediate phenotype that blends the traits associated with each allele.
What is incomplete dominance with ‘Protein production’ ?
Both alleles produce proteins, but 1 may be less functional or produce a different variant.
What is incomplete dominance with ‘Protein Quantity’ ?
Heterozygous individuals produce a reduced amount of functional protein compared to homozygous individuals.
What is an example of incomplete dominance in humans?
Curly hair and straight hair are incompletely dominant alleles of one gene. A person with two curly alleles will have very curly hair. A person with two straight alleles will have straight hair. A person with one curly and one straight allele will have wavy hair!
