inhertitence

Question 1

genotype

Answer 1

genetic constitution of an organism

Question 2

phenotype

Answer 2

the expression of the genotype and its interactions with the environment

Question 3

alleles

Answer 3

variant of a particular gene

Question 4

what causes multiple alleles

Answer 4

occurs due to mutations in a gene that occur at different position in a gene

Question 5

homozygotes

Answer 5

same type of allele

Question 6

heterozygous

Answer 6

both alleles are different

Question 7

dominant

Answer 7

expressed in the phenotype of a heterozygote, only 1 copy needed for expression

Question 8

recessive

Answer 8

not expressed in the phenotype of a heterozygote, so 2 copies are needed for expression

Question 9

codominant alleles

Answer 9

equally dominant and equally expressed in phenotype e.g. blood type AB

Question 10

monohybrid cross

Answer 10

used to predict outcome of 2 different genotypes

Question 11

what is the layout of a monohybrid cross

Answer 11

1. parental genotype
2. Gametes
   3: cross

Question 12

Test crosses

Answer 12

used to determine unknown genotype
unknown genotype crosses with homozygous recessive individual
if all offspring have dominant phenotype - genotype is homozygous dominant
if half offspring have recessive phonotype the unknown is heterozygous

Question 13

dihybrid cross

Answer 13

inheritance of 2 different genes

Question 14

autosomal linkage

Answer 14

tow or more genes located on the same autosome

Question 15

how does autosomal linked genes inherited together and why (not)?

Answer 15

less likely to be seperated during crossing over so are inherited together

Question 16

how does autosomal linkage affect the offspring genotype

Answer 16

offspring more likely to resemble parental genotype, effects ratio

Question 17

sex linkage

Answer 17

gene is on X chromosome (or Y)

Question 18

how does this affect inheritance of genes in offspring?

Answer 18

males more likely to inherit recessive condition as only require 1 copy for it to be expressed in the phenotype (as males only have 1 X)

Question 19

epistasis

Answer 19

interaction between 2 genes where one gene masks the expression of the other gene in the phenotype

Question 20

what is the gene that supressed the gene called

Answer 20

epistatic gene

Question 21

what is the gene that’s being repressed by the epistatic gene called

Answer 21

hypostatic gene

Question 22

can epistatic interaction be dominant or recessive?

Answer 22

yes, both

Question 23

chi squared test

Answer 23

determines the probability of an unexpected result being due to chance or being significant

Question 24

what is the null hypothesis

Answer 24

any difference that occurs between observed and expected results is due to chance