6.1.2 Patterns of Inheritance

Question 1

What is the phenotype?

Answer 1

The appearance of the organism (the way the characteristic is displayed)

Question 2

What influances the phenotype?

Answer 2

The genotype and environment

Question 3

What genetic factors cause variation?

Answer 3

Mutation

Question 4

What are mutagens?

Answer 4

Things that cause mutations

Question 5

What are examples of mutagens?

Answer 5

x-rays, Gamma Rays, UV light.
Toxic Gases.
Viruses.

Question 6

What mutations can you have?

Answer 6

Specific genes.
Chromosomes.

Question 7

Are phenotypes caused by changed genetics passed on?

Answer 7

Yes - the offspring could have the same phenotype

Question 8

Are phenotypes caused by environmental factors passed on?

Answer 8

No - they don’t change the genes so don’t get passed onto offspring

Question 9

What are examples of phenotypes caused by enviromental factors?

Answer 9

Speakign with a certain dialect.
Loosing a limb.
Having Scars.
Beaks - as a result of diet.

Question 10

What is etiolation?

Answer 10

Plants growing in a partial or complete lack of light.

Question 11

What happens to a plant during etiolation?

Answer 11

Leaves do not develop and the lack of chlorophyll means that the plant is yellow or yellow-white.
The plant is described as chlorotic or suffering from chlorosis.

Question 12

How is chlorosis an example of environment changing the phenotype?

Answer 12

Chloric plants have the genes to produce chlorophyll but due to the environmental factors, it isn’t turned on.

Question 13

When do you use a monohybrid cross?

Answer 13

For simple tests involving only one characteristic with one pair of contrasting traits.

Question 14

What gametes are produced from homozygous parents?

Answer 14

The allele for the individual. Either Dominant or recessive.
e.g.
TT -> T X2
tt -> t X2

Question 15

What gametes are produced from heterozygous parents?

Answer 15

One of each type of allele that they have.
e.g.
Tt -> T and t

Question 16

What is the ratio for a monohybrid cross of heterozygous parents?

Answer 16

3:1
Dominant : Recessive

Question 17

How do you set up a punnet square?

Answer 17

All possible gametes are arranged in rows. Females vertically and males horizontally.
The predicted genotypes of the next generation are produced by combining the male and female gametes

Question 18

What does it mean to have multiple alleles?

Answer 18

The gene has more than two alleles. However, an individual can only possess two alleles at a time - one on each gene locus in a pair of homologous chromosomes.

Question 19

What are the Human blood groups?

Answer 19

A, B, O, AB

Question 20

What are the alleles for human blood groups?

Answer 20

Ia, Ib, Io

Question 21

What alleles are dominant and recessive in the human blood groups?

Answer 21

Ia and Ib are dominant.
Io is recessive.

Question 22

What happens if you get both Ia and Ib appearing on the gene for blood group?

Answer 22

You have the blood group AB. They share dominance - an example of co-dominance.

Question 23

What colour is an agouti rabbit?

Answer 23

Grey base, Yellow band and a black tip.

Question 24

What colour is an albino rabbit?

Answer 24

White - no pigment develops.

Question 25

What colour is a chinchilla rabbit?

Answer 25

Silvery grey - lack the yellow band of agouti.

Question 26

What colour are Himalayan rabbits?

Answer 26

White with black feet, nose ears and tails.

Question 27

What effects the colour of rabbits?

Answer 27

A single gene that has 4 alleles.
C - Agouti
Cch - Chinchilla
Ch - Himalayan
c - Albino

Question 28

What is the dominant higharqy of for rabbit fur colour?

Answer 28

C - Agouti is most dominant
Cch - Chinchilla is more dominant than Ch - Himalayan. c - Albino is recessive to all others.