Unit 7 Genetics, Populations, Evolution And Eco Systems Flashcards
What is monohybrid inheritance?
The inheritance of a single gene.
What is dihybrid inheritance?
How 2 characters , determined by 2 different genes located on 2 different chromosomes are inherited.
What is codominance?
Occurs where instead of one allele being dominant and the other recessive, both alleles are equally dominant. This means both alleles of a a gene are expressed in the phenotype.
What is multiple alleles?
A gene may have two or more alleles eg inheritance of human blood group ABO.
When does epistasis arise?
When the allele of one gene affects or masks the expression of another in the phenotype.
What is the chi-squared test used to test?
The null hypothesis. The null hypothesis is used to examine the results for scientific investigations and is based on the assumption that there will be no statistically significant difference between sets of observations, any difference being due to chance. Chi- squared is a means of testing whether any deviation between the observed and expected numbers in an investigation is significant or not.
What criteria has to be met for the chi-squared test?
Sample size which is relatively large
Data must fall into discrete categories
Only raw counts and not percentages, rates etc can be used
Compares experimental results with real ones
Formula of chi-squared test
Sum of : (Observed numbers - expected numbers) 2 / expected numbers
What happens after we obtain the value of chi-squared?
What happens after we obtain the value of chi-squared?
