inheritance

Question 1

gene

Answer 1

section of DNA that codes for a specific protein
protein used by the cell for a specific function

Question 2

genotype

Answer 2

the genetic constitution of an organism

Question 3

gene pool

Answer 3

all the alleles within an interbreeding population

Question 4

population

Answer 4

all the individuals of the same species that occupy the same habitat at the same time

Question 5

phenotype

Answer 5

expression of its genetic constitution and its interaction within the environment

Question 6

allele

Answer 6

different version of the same gene
dominant , recessive or codominant

Question 7

multiple alleles

Answer 7

more than 2 alleles for the same gene
produces a hierarchy of dominance

Question 8

locus

Answer 8

different alleles for the same gene are found at the same position on the homologous chromosome

Question 9

homozygous

Answer 9

organism has two copies of the same allele

Question 10

heterozygous

Answer 10

two copies of a gene are different alleles

Question 11

dominant allele

Answer 11

always expressed in the phenotype

Question 12

recessive allele

Answer 12

only expressed in the phenotype if the genotype is homozygous

Question 13

codominant alleles

Answer 13

equally expressed within the phenotype
eg C(r)C(w)
cross 2 heterozygous always 1:2:1 ratio

Question 14

pedigree charts
dominant characteristic rules

Answer 14

affected offspring must have at least 1 affected parent
unaffected parent only have unaffected offspring
if both parents affected and have an unaffected offspring both parents must be heterozygous

Question 15

hardy weinburg equations

Answer 15

p + q = 1
p^2 +2pq + q^2 = 1
P = frequency of dominant allele
q = frequency of recessive allele
p^2 = frequency of homozygous dominant
2pq = frequency of heterozygous
q^2 = frequency of homozygous recessive

Question 16

what does hardy weinburg predict

Answer 16

the allelic frequencies of a particular gene will remain constant over generation

assumes there is no
mutations
migration or emigration
selection for a particular allele
large population
mating is random

Question 17

monohybrid inheritance

Answer 17

normal
inheritance of a single gene which determines a single characteristic
if you cross 2 heterozygous individuals together always a 3:1 ratio

Question 18

pedigree charts
recessive characteristic rules

Answer 18

unaffected parents can have an affected offspring if they are heterozygous

Question 19

sex linked genes

Answer 19

gene found on the x chromosome
a female would need to have two copies of a recessive allele for it to appear in the phenotype whereas male only need one

Question 20

in who are sex linked genes more common

Answer 20

more common in males
they show a mother to son inheritance pattern and often skip a generation

Question 21

to prove a characteristic is not sex linked

Answer 21

dads and daughters
-if a daughter is affected
-her father is not
-it is a recessive characteristic
-it is not sex linked

mothers and sons
-if a son is affected
-his mum is not
-it is a dominant characteristic
-it is not sex linked

Question 22

dihybrid inheritance

Answer 22

when an organism has two genes linked on the same chromosome or on different chromosome
eg AaBb
gametes are
AB Ab aB ab
double heterozygote ratio - 9:3:3:1

Question 23

autosomal linked

Answer 23

when 2 genes are automally linked they do not follow the expected phenotypic ratio for a dihybrid cross between heterozygous parents

Question 24

epistatis

Answer 24

interaction between 2 genes where one allele influences the expression of another
ratios add up to 16 but do not show 9:3:3:1