Inheritence Flashcards
What is a monohybrid cross?
When 2 monohybrids have a child and pass on the dominant and recessive genes
What is a monohybrid?
An organism that has the genes for both variations of one trait (hetrozygous)
What are te 3 modes of inheritence?
- Autosomal: Anything on chromosomes 1 - 22
- Sex-linked: Anything on the X or Y chromosomes
- X-linked: Anything on the X chromosome
What is a test cross?
Used to determine an unknown genotype of an organism with a dominant phenotype, by breeding with an organism with a known genotype.
What does multiple alleles mean?
When more than 2 alleles are involved in the inheritance of a trait
What is codominance?
When both alleles are dominant so both are represented in the phenotype. eg AB blood type
What is incomplete dominance?
When both alleles are dominant but neither is completely dominant over the other so the trait blends
What are polygenes?
When 2 or more genes contribute to the phenotype. A gene where alleles have a small additive effect on the phenotype. Distribution of these traits follow a bell curve.
What is continuous variation?
Polygenic inheritance with multiple alleles and multiple genes with no set groups. eg height, weight
What is discontinuous variation?
Single gene inheritance with multiple alleles. Set groups, no in-between. eg bloog groups
What is a karyotype?
Chart of all chromosomes in an individual
What are 2 important things about X-linked genes regarding inheritance?
- X-linked recessive genes will always be expressed in males, a female can be a carrier and not express the trait
- A make with an X-linked dominant trait will pass it on to all his daughters
