Inheritance

Question 1

Meaning of multiple alleles

Answer 1

More than 2 alleles

But only 2 can be present

Question 2

How do you draw co-dominance in the diagram

Answer 2

Use superscript on a letter

ie small letters floating in the air next to the big letter

Question 3

What is the dominance hierarchy

Answer 3

sometimes if more than 3 alleles they’re arranged in a hierarchy
Dominant above, recessive below

Question 4

In a pedigree chart, what does a square represent?

Answer 4

Male

Question 5

In a pedigree chart, what does a circle represent

Answer 5

Female

Question 6

In a pedigree chart, what does shading represent?

Answer 6

Sufferer

Question 7

In a pedigree chart, what does half shading or a dot represent?

Answer 7

Carrier

Question 8

Meaning of co-dominance

Answer 8

Both alleles are equally dominant

Question 9

What is the hardy-Weinberg equation used for?

Answer 9

Predicting the number of dominant and recessive alleles in a population

Question 10

What is the hardy-Weinberg equation?

Answer 10

P2 + 2pq + q2

Question 11

What does allelic frequency mean?

Answer 11

The number of times an allele occurs in a gene pool

Question 12

what is a gene pool

Answer 12

All the alleles of all the genes of all the individuals in a population at any one time

Question 13

In the hardy-Weinberg equations what does P2 represent

Answer 13

Homozygous dominant

Question 14

In the hardy-Weinberg equation what does q2 represent?

Answer 14

Homozygous recessive

Question 15

In the hardy-Weinberg equation what does 2pq mean?

Answer 15

Heterozygous

Question 16

When can’t you use the hardy-Weinberg equation?

Answer 16

If small population
If mutations arise
If individuals are mating randomly
If natural selection happening
If gene flow between populations from migration or transfer of gamets

Question 17

What does it mean if a population is said to be in hardy-Weinberg equilibrium

Answer 17

A population’s genotype and allele frequencies will remain unchanged over successive generations

Question 18

How do you work out the genes in a population using the hardy-Weinberg equation?

Answer 18

Get q2
Square root it to find q
Do p = 1 - q
Do p2 by doing p xs p
Put back into equation

Question 19

What is the process of speciation

Answer 19

Mutation creates variation
Geographical isolation 
Breeding between them prevented
Selections pressures different
Advantage
Survive and reproduce
Alleles frequency increase or decrease
Speciation

Question 20

What happens to two groups of animals if speciation occurs

Answer 20

They can no longer produce fertile offspring if they breed

Question 21

What is directional selection

Answer 21

Selections favours individuals that vary in one direction from the mean of the population

Question 22

What is stabilising selection

Answer 22

Selection favours average individuals

Question 23

What happens if directional selections occurs

Answer 23

Characteristics of populations changes, new mean created

Question 24

What happens if stabilising selection occurs

Answer 24

Characteristics of population is preserved

Question 25

Explain what is meant by a recessive allele

Answer 25

Expressed in phenotype if homozygous

Question 26

The observed ratio of offspring is not the same to the expected ratio from theory. Explain why

Answer 26

Chance related to mating
Random fusing of gametes
Small sample size

Question 27

Why is the estimated percentage of heterozygous in the population likely to be lower than the actual percentage in the population. Explain why

Answer 27

Small gene pool
Small founder population
High probability of mating with person having recessive alleles