Past Mock Questions

Question 1

What term is used to describe a group of organisms that produce fertile young after interbreeding?

Answer 1

Species

Question 2

Explain the role of genes in the process of heredity

Answer 2

Genes are responsible for passing on characteristics/traits from parent to offspring

Question 3

The formation of which type of biomolecule is controlled by genes?

Answer 3

Proteins

Question 4

All human genes have sections of DNA whose function is unknown. What name is given to these sections?

Answer 4

Non-coding or junk DNA

Question 5

Explain what is meant by the term DNA profilling

Answer 5

A method of making a unique a pattern of bands from the DNA of a person, which can then be used to compare with the DNA profile of another person

Question 6

During DNA profiling the DNA is cut into fragments.

Explain how this process occurs

Answer 6

Through the use of restriction enzymes

Question 7

Having obtained the fragment of DNA, describe the process which much occur in order to produce a DNA profile
(6)

Answer 7

The fragments are separated by a process called gel electrophoresis

An electric current is applied to a sugar-based gel containing the invisible DNA fragments

The small DNA fragments are separated from the larger fragments as they can travel faster through the gel

A radioactive material is added to the gel which produces a fluorescent image when combined with DNA

A photographic copy of the final pattern of DNA bands is obtained

The patterns are then compared

Question 8

As part of your laboratory investigation you isolated DNA from plant tissue

Describe one step you carried out to release the DNA from the plant cell
(2)

Answer 8

Washing up liquid was added to the solution of water, salt and chopped up onion

The washing up liquid dissolved the cell and the nuclear membranes to release the DNA from the cell

Question 9

As part of your laboratory investigation you isolated DNA from plant tissue

What was added at the end of the procedure to make the threads of DNA visible?

Answer 9

Freezer cold ethanol

• Not ‘ice cold’
• Freezer cold is the only acceptable answer

Question 10

Give one application of DNA profiling

1/2

Answer 10

Used in forensic science to compare DNA samples from a crime seem with that of a suspect

This can identify if a suspect was associated with a crime

It can also be used to identify the paternity or maternity of a child

Question 11

What is an allele?

Answer 11

Alleles are different/alternative forms of the same gene

Question 12

What is the significance of an allele not being linked?

1/3

Answer 12

This means independent assortment can occur

There can be a greater variety of offspring

Either of a pair of alleles is equally likely to combine with either of another pair of alleles

Question 13

Define the term evolution

Answer 13

Evolution is the way in which living things change genetically to produce new forms of life over long periods of time

Question 14

Name the mechanism proposed by the Darwin-Wallace theory to explain evolution

Answer 14

Natural Selection

Question 15

In genetics, what is meant by variation?

Answer 15

Variation within a species means that a group of successfully interbreeding organisms the individual members show different characteristics

Question 16

Explain the link between variations and mutations

Answer 16

Mutations can be caused by variations and variations can be caused by mutations

Question 17

What is a gene mutation?

Answer 17

A gene mutation is a change in a single gene

Question 18

Give one example of a disorder caused by a gene mutation

1/5

Answer 18

Sickle-cell anaemia 
Colour blindness 
Cystic Fibrosis 
Albinism 
Haemophilia

Question 19

Explain what is meant by ‘species’

Answer 19

A species is a group of similar organisms that are capable of naturally interbreeding

Question 20

State one piece of evidence to support the Darwen-Wallace theory of natural selection

Answer 20

The existence of fossils

Question 21

Name the type of nucleic acid that contains the sugar deoxyribose

Answer 21

DNA

Deoxyribose nucleic acid

Question 22

Name the group of chemicals to which nitrogenous compound found in nucleic acids belong

Answer 22

Bases

Question 23

With reference to protein synthesis explain what is meant by:

Translation

Answer 23

The conversion of a sequence of genetic bases on messenger RNA into a sequence of amino acids

Question 24

With reference to protein synthesis explain why the process of joining amino acids together to form a protein eventually cease.

Answer 24

This process will continue until the stop codon is reached

Question 25

Human growth hormone can now be produced by bacteria

Explain the role of genetic screening in this process

Answer 25

Genetic screening identifies the gene responsible for producing growth hormone

Question 26

Human growth hormone can now be produced by bacteria

Explain the role played by bacteria in the production of this hormone
7

Answer 26

The plasmid of a bacteria cell is isolated

The plasmid is cut open using restriction enzymes

The target gene is cut from it’s chromosome using the same restriction which ensures the sections will be complementary to each other

The cut plasmid and target gene sections are combined by base pairing

The plasmid is returned to the bacterial cell

The bacterial containing the target gene are cloned

The bacterial cell reproduce and form their product (human growth hormone) - often occurs in a bioreactor

Question 27

For a new species to be formed what conditions must be met by all offspring

Answer 27

The offspring must be fertile

Question 28

Give one example of variation in humans

Answer 28

Different eye colour

Question 29

Name one cause of different eye colour in humans

Answer 29

Sexual reproduction and independent assortment

Question 30

Explain the term non-coding DNA

Answer 30

DNA that does not cause the production of a protein

Question 31

Name the sugar found in DNA nucleotides

Answer 31

Deoxyribose

Question 32

What is the function of restriction enzymes in the process of DNA profiling?
(2)

Answer 32

Restriction enzymes cut DNA into fragments

Each different restriction enzyme cuts DNA at specific base sequences

Question 33

Write out the complementary base pair of the STR ACTT

Answer 33

TGAA

Question 34

Name the type of bonding found between complementary base pairs

Answer 34

Hydrogen bonds