8. Genotype and Phenotype - Patterns of Inheritance Flashcards
What is genetics the study of?
Inheritance and variation (from mutation and meiosis).
Define homozygous.
Two alleles of a gene that are the same.
Define heterozygous.
Two alleles of a gene that are different.
Define hemizygous.
There is only one allele of a gene on the X chromosome.
Define dominant.
An allele that determines the phenotype of the individual.
Define recessive.
The non-dominant allele of an individual.
What are the five types of inheritance?
Autosomal dominant, autosomal recession, X-linked dominant, X-linked recessive and Y-linked.
For the following types of inheritance are males and females equally affected?
a. Autosomal recessive
b. Autosomal dominant
c. X-linked recessive
d. X-linked dominant
a. Yes
b. Yes
c. No, males are more affected
d. No, every male will be affected so more than females
What is the chance of two heterozygotes having offspring affected by an autosomal recessive disorder?
25%.
What is the chance of two affected individuals having offspring with an autosomal recessive disorder?
100%.
What is the chance of an affected individual having offspring affected by the autosomal dominant disorder?
50%.
What is the chance of a heterozygous female carrier having a son affected by X-linked recessive disorder?
50%
What is an example of co-dominance?
Blood types, AB blood type.
What is complementation in genetic inheritance?
More than one gene involved in producing a phenotype.
What are genes on the same chromosome said to be?
Linked.
