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DA genetics

Total questions: 20

Worksheet time: 11mins

Name
Class
Date
1.

Cystic fibrosis is caused by having two copies of a recessive allele (ff). A carrier of cystic fibrosis has the genotype Ff. A person with the genotype FF is neither a carrier nor a sufferer.

The genotype of a carrier would be described as:

a)

Homozygous recessive

b)

Heterozyogous

c)

Homozygous dominant

d)

Heterozygous recessive

2.

Cystic fibrosis is caused by having two copies of a recessive allele (ff). A carrier of cystic fibrosis has the genotype Ff. A person with the genotype FF is neither a carrier nor a sufferer.

What are the possible genotypes of children born to two carriers?

a)

FF & ff

b)

FF & Ff

c)

Ff & ff

d)

FF, Ff & ff

3.

A person with cystic fibrosis has a gene mutation. This means

a)

They have a missing gene

b)

They have an extra chromosome

c)

The amino acid sequence of their DNA is incorrect

d)

The base sequence of their DNA is incorrect

4.

A white flower has the genotype GG and a pink flower has the genotype gg.

Select ALL possible parents of a heterozygous plant

a)

GG and GG

b)

gg and gg

c)

Gg and Gg

d)

GG and gg

5.

A human has 46 chromosomes in their skin cell nucleus. If they are male then they have

a)

46 matching pairs

b)

22 matching pairs

c)

23 matching pairs

d)

Two X chromosomes

6.

Which phrase best describes a heterozygous genotype?

a)

There are two dominant alleles

b)

The individual will display the dominant phenotype

c)

The individual will display the recessive phenotype

d)

There are two recessive alleles

7.

The gene for freckles has two forms. One form will cause the individual to have freckles and the other form will prevent freckles being visible. Different forms of a gene are called (a)   .

8.

Which is the correct Punnett square to show a cross between a homozygous dominant parent and a heterozygous parent?

a)

b)

c)

d)

9.

A man with Huntington's disease has the genotype Hh. His sperm cells will contain

a)

Only H alleles

b)

Only h alleles

c)

Either H or h alleles

d)

Neither H nor h alleles

10.

Which statement is FALSE ?

a)

A human male has an X and Y chromosome

b)

A human male has an X and X chromosome

c)

A human female has an X and X chromosome

d)

A human female has no

Y chromosomes

11.

The photograph shows the chromosomes from a person who has 47 chromosomes. Choose the correct statement.

a)

This is a female who has Down Syndrome

b)

This is a female who does not have Down Syndrome

c)

This is a male who has Down Syndrome

d)

This is a male who does not have Down Syndrome

12.

A mutation in fruit flies causes them to have small non functioning wings called vestigial wings. A normal fly is either NN or Nn, but a vestigial wing fly is nn.

What would you cross a normal winged fly with to determine its genotype?

a)

NN

b)

nn

c)

nn or Nn

d)

NN or nn

13.

A heterozygous wild type male (Nn) is crossed with a heteozygous wild type female (Nn). If they produce 200 offspring, how many of them should be wild type

a)

200

b)

150

c)

100

d)

50

14.

A section of DNA which carries the code for the production of a protein is called a (a)   .

15.

In the technique of amniocentesis

a)

the mother's blood is tested for genetic disorders

b)

the baby's blood is tested for genetic disorders

c)

the fluid around the baby is tested for genetic disorders

d)

the baby's cells are tested for genetic disorders

16.

Which statement best describes a dominant allele?

a)

An allele which affects phenotype when there is at least one copy

b)

An allele which affects phenotype only when there are two copies

c)

An allele which is masked by a recessive allele

d)

An allele which is never passed on to offspring

17.

Yellow alleles are dominant over orange. A pure breeding orange flowered plant is bred with a pure breeding yellow plant, so

a)

all offspring will be yellow

b)

offspring will be yellow or orange in a 2:1 ratio of orange to yellow

c)

all offspring will be orange

d)

offspring will be yellow or orange in a 3:1 ratio of orange to yellow

18.

In pigs, short hair (H) is dominant over long hair (h). If a heterozygous pig is crossed with a long haired pig then

a)

All the offspring will have short hair

b)

The expected offspring ratio of short haired to long haired is 3:1

c)

The expected offspring ratio of short haired to long haired is 2:1

d)

The expected offspring ratio of short haired to long haired is 1:1

19.

When a gene is mutated, what changes in the DNA?

a)

The sugar-phosphate backbone

b)

The amino acids

c)

The order of the bases

d)

The shape of the protein

20.

There are two forms of the Scops Owl. The grey form is dominant, but the tan form has a homozygous recessive genotype. The pair shown here had 4 chicks, 3 were tan and 1 was grey. We can conclude that:

a)

The grey parent was homozygous

b)

Some of the chicks died before hatching

c)

The grey parent was heterozygous

d)

The tan parent was the female