Inheritance Flashcards
Genotype
The genetic constitution of an organism (the alleles it has for a gene)
Phenotype
The expression of the genes and its interaction with the environment
Homozygous
A pair of homologous chromosomes carrying the same alleles for a single gene
Heterozygous
A pair of homologous chromosomes carrying two different alleles for a single gene
Recessive allele
An allele only expressed if no dominant allele is present
Dominant allele
An allele that will always be expressed in the phenotype
Codominant
Both alleles are equally dominant and expressed in the phenotype
Multiple alleles
More than two alleles for a single gene
Sex-linkage
A genus whose locus is on the X chromosome
Autosomal linkage
Genes that are located on the same chromosome (not the sex chromosomes)
Epistasis
When one gene modifies or masks the expression of a different gene at a different locus
Monohybrid
Genetic inheritance cross of a characteristic determined by one gene
Dihybrid
Genetic inheritance cross for a characteristic determined by two genes
Null hypothesis wording
There is no significant difference between the expected and observed frequency of …
Probability value when degree of freedom = 1
0.05
Critical value is normally…
3.841
If chi squared is less than critical value then …
There is more than 5% probability that the results are due to chance
The null hypothesis is accepted
There is no significant difference between observed and expected results
Gene
Small section of DNA which codes for a polypeptide
Allele
Alternative form of a gene
Crossing over
Provides a new combination of alleles during meiosis
Gene pool
All the alleles of all the genes within a population at one time
Population
All the individuals of one species in one area at one time
Allele frequency
The proportion of an allele within the gene pool
Assumptions made in Hardy Weinberg
No change in allele frequency between one generation and the next:
- No migration
- No mutation
- No selection
- Mating is random
- Large population
