Biology Unit 1 Chapter 6 – Immunity
Final Exam Questions With Solved
Solutions.
Changes to the protein coat of the influenza virus cause antigenic variability. Explain how antigenic
variability has caused some people to become infected more than once
with influenza viruses. (2) - Answer Memory B cells do not recognise new antigens;
Antibodies previously produced are not effective
(Refer to exam q) The drawings show the changes in a B lymphocyte after stimulation by specific
antigens. Explain how the changes shown in the drawings are related to the function of B lymphocytes.
(4) - Answer Mitochondria provide more energy;
More RER to synthesise proteins;
More Golgi apparatus to modify and package proteins;
These are necessary because B lymphocytes produce antibodies
What is vaccination? (2) - Answer Injection of antigens;
Antigens from dead microorganisms
(Refer to exam q) A test has been developed to find out whether a person has antibodies against the
mumps virus. The test is shown in the diagram. Explain why this test will detect mumps antibodies, but
not other antibodies in the blood. (1) - Answer 2nd antibodies specific to mumps antibody
Explain why it is important to wash the well at the start of Step 4. (2) - Answer Removes unbound 2nd
antibodies;
Otherwise enzyme may be present and changes colour of the solution anyway
Explain why there will be no colour change if mumps antibodies are not present in the blood. (2) -
Answer No antibodies to bind to antigen;
, Therefore 2nd antibody with the enzyme wont bind
The box jellyfish produces a poison (venom) which enters the blood when a person is stung. A person
who has been stung can be treated with an injection of antivenom. This antivenom is produced by
injecting small amounts of venom from box jellyfish into sheep, then
extracting antibodies from the sheeps' blood. These antibodies are then injected into the person who
has been stung.
If a sheep is injected with the box jellyfish venom on more than one occasion a higher yield of antivenom
is obtained. Explain why. (2) - Answer Stimulates memory cells;
So antibodies produced quicker
Injecting antivenom does not give a person lasting protection against the venom of box jellyfish. Explain
why. (2) - Answer Passive immunity;
No memory cells produced
Suggest one possible problem in injecting people with antivenom made in this way. (1) - Answer Could
transfer disease
Some new tests use monoclonal antibodies. Explain why these antibodies are referred to as monoclonal.
(1) - Answer Antibodies produced from the same B cell
Tests using monoclonal antibodies are specific. Use your knowledge of protein structure to explain why.
(3) - Answer Specific primary structure;
Specific tertiary structure;
So only complementary to one antigen
The tests using monoclonal antibodies allow vets to identify brucellosis while they are still on a farm.
Explain the advantages of this. (3) - Answer Rapid treatment of infected cattle;
Reduces spread of disease;
Prevents the death of non-infected animals
Final Exam Questions With Solved
Solutions.
Changes to the protein coat of the influenza virus cause antigenic variability. Explain how antigenic
variability has caused some people to become infected more than once
with influenza viruses. (2) - Answer Memory B cells do not recognise new antigens;
Antibodies previously produced are not effective
(Refer to exam q) The drawings show the changes in a B lymphocyte after stimulation by specific
antigens. Explain how the changes shown in the drawings are related to the function of B lymphocytes.
(4) - Answer Mitochondria provide more energy;
More RER to synthesise proteins;
More Golgi apparatus to modify and package proteins;
These are necessary because B lymphocytes produce antibodies
What is vaccination? (2) - Answer Injection of antigens;
Antigens from dead microorganisms
(Refer to exam q) A test has been developed to find out whether a person has antibodies against the
mumps virus. The test is shown in the diagram. Explain why this test will detect mumps antibodies, but
not other antibodies in the blood. (1) - Answer 2nd antibodies specific to mumps antibody
Explain why it is important to wash the well at the start of Step 4. (2) - Answer Removes unbound 2nd
antibodies;
Otherwise enzyme may be present and changes colour of the solution anyway
Explain why there will be no colour change if mumps antibodies are not present in the blood. (2) -
Answer No antibodies to bind to antigen;
, Therefore 2nd antibody with the enzyme wont bind
The box jellyfish produces a poison (venom) which enters the blood when a person is stung. A person
who has been stung can be treated with an injection of antivenom. This antivenom is produced by
injecting small amounts of venom from box jellyfish into sheep, then
extracting antibodies from the sheeps' blood. These antibodies are then injected into the person who
has been stung.
If a sheep is injected with the box jellyfish venom on more than one occasion a higher yield of antivenom
is obtained. Explain why. (2) - Answer Stimulates memory cells;
So antibodies produced quicker
Injecting antivenom does not give a person lasting protection against the venom of box jellyfish. Explain
why. (2) - Answer Passive immunity;
No memory cells produced
Suggest one possible problem in injecting people with antivenom made in this way. (1) - Answer Could
transfer disease
Some new tests use monoclonal antibodies. Explain why these antibodies are referred to as monoclonal.
(1) - Answer Antibodies produced from the same B cell
Tests using monoclonal antibodies are specific. Use your knowledge of protein structure to explain why.
(3) - Answer Specific primary structure;
Specific tertiary structure;
So only complementary to one antigen
The tests using monoclonal antibodies allow vets to identify brucellosis while they are still on a farm.
Explain the advantages of this. (3) - Answer Rapid treatment of infected cattle;
Reduces spread of disease;
Prevents the death of non-infected animals
