Inheritance + populations (hardy weinberg) Flashcards Preview

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Flashcards in Inheritance + populations (hardy weinberg) Deck (26):
1

what is the definition of genotype

genotype is the genetic constitution of an organism

genotypes are the genes

2

what is the phenotype

phenotype is the expression of this genetic constitution and its interaction with the environment.

phenotype is what we see ( how the genes express)

3

what are alleles

different versions of the same gene

4

what is meant by the term dominant

the dominant allele masks the effect of the other.

5

what is meant by the term codominant

both alleles are expressed so the phenotype is a combination of both alleles e.g. red and white alleles making pink phenotype

6

what is meant by the term recessive

the recessive allele is masked by a dominant one

7

what is meant by homozygous

both alleles at a specific gene locus are the same. could be homozygous recessive or dominant

8

what is meant by the term heterozygous

the alleles at a specific gene locus are different

9

what does monohybrid inheritance mean

the inheritance of a single gene e.g. plant height

10

what does dihybrid inheritance mean

the inheritance of two seperate genes

11

what is meant by sex linkage

sex linkage is when an allele that codes for a characteristic is found on the sex chromosome. It is therefore inherited with the sex
e.g gene for colour vision, haemophilia

12

what is meant by autosomal linkage

autosomal linkage is when two genes are found on the same chromosome they are therefore very likely to be inherited together

the closer two genes are, the more likely they are to be inherited together

13

multiple alleles

when there are more than two alleles
e.g. blood group A B O

14

what is the formula for chi squared

(Observed-Expected)^2/Expected

^2= squared
/=divided by

15

epistasis

the interaction of one gene upon another gene

16

what is a population

group of organisms of the same species occupying a particular space at a particular time that can potentially interbreed.

17

what is a gene pool

all of the alleles of all the genes in a population

18

what is the definition of allele frequency

the likelyhood of one allele being at a specific gene locus

19

what is a species

a group of organisms that breed to make fertile offspring

20

what is the hardy-weinberg equation

p^2 + 2pq + q^2=1

p+q=1

21

in the equation p+q=1 what is p

the allele frequency of the dominant allele

22

in the equation p+q=1 what is q

the allele frequency of the recessive allele

23

define the terms of the hardy weinberg equation

p^2 - the frequency of the homozygous dominant genotype
2pq-the frequency of heterozygous genotype
q^2- the frequency of the homozygous recessive genotype

24

what does the hardy weinberg principle predict

that the allele frequency in a population will not change- the population is in a hardy weinberg equilibrium

25

what assumptions/ conditions does the population have to fulfil to be a Hardy weinberg population

No selection based on trait. e.g eye colour
no mutation
large population

26

if you are given the percentage of people who have the recessive phenotype, how do you solve the hardy weinberg equation

convert percentage of recessive phenotype into decimal this is q^2

square root the decimal. this is q

1-q=p

put these numbers back into the equation