The Search for Better Health.

Question 0

Which of the following prevents the entry of pathogens into the human body?

A) Cell death to seal off a pathogen
B) Mucus lining the respiratory tract
C) Phagocytosis performed by B cells
D) Destruction of pathogens by the lymphatic system

Answer 0

B

Question 1

What are the main components of the immune response involved in organ rejection?

A) Antibodies, T cells and B cells
B) Antibiotics and white blood cells
C) T cells, B cells and red blood cells
D) Red blood cells, white blood cells and antigens

Answer 1

A

Question 2

Vaccination can control the spread of

A) a genetic disorder.
B) an infectious disease.
C) a nutritional deficiency.
D) an environmental disease.

Answer 2

B

Question 3

Why are quarantine measures needed when there is an outbreak of an infectious disease in Australian farm animals?

A) To prevent the spread of the disease to food imported into Australia
B) To prevent Australian farm animals from becoming immune to the disease
C) To prevent introduced plants threatening the survival of Australian farm animals
D) To prevent the disease from spreading to farm animals in different regions of Australia

Answer 3

D

Question 4

Describe the difference between the roles of TWO named types of T cells in the immune response in humans.

Answer 4

Includes:
-The T helper cell is part of an initial response to an antigen, releasing chemicals to stimulate growth of B cells that respond to the antigen. A T memory cell responds differently, interacting initially with an antigen but remaining dormant until the next time the body is infected, when it is quickly activated so that there is a faster response to the antigen.

Question 5

Outline the work done by Morgan that has led to our understanding of sex linkage.

Answer 5

Includes:
-Morgan bred fruit flies and observed that the eye colour was not inherited in normal
Mendelian ratios. The white eye colour was common in males and rare in females.

Question 6

List TWO observations that indicated the presence of pathogens on plant shoots and/or leaves.

Answer 6

Includes:
-Black spots on leaves; appearance of ‘fur’(mould) on the leaf; white spots/growth on shoots;
presence of abnormal tissue growth on/in leaves/shoots.

Question 7

Define gene expression.

Answer 7

Includes:
-Gene expression refers to a gene being ‘turned on’. When a gene is ‘turned on’ the coded information in the gene is used to produce a polypeptide. Gene expression causes cells to differentiate into particular types of cells.

Question 8

What is a promoter?

Answer 8

Includes:

-A promoter is a regulatory area at the start of a gene that acts as the binding site for RNA polymerase.

Question 9

Outline a way which will cause a gene not to be expressed.

Answer 9

Includes:

• The interruption or alteration in the process of producing a particular polypeptide means a particular chemical reaction may be unable to occur, which may lead to a disease.
• If there is a problem with the promoter there will be a problem with transcription and thus the polypeptide will not be synthesised and the gene will not be expressed.

Question 10

Use an example to show how a knowledge of gene expression could aid sufferers of a particular disease.

Answer 10

Includes:

-

Question 11

What is cancer?

Answer 11

Includes:
-Cancer involves the rapid cell division without cell differentiation so that a mass of cells accumulates in one place forming a tumour.

Question 12

Explain the difference between a pair of identical twins that developed from the same fertilised egg, and the two genetically identical animals produced as a result of nuclear transfer cloning.

Answer 12

Includes:
- Nuclear transfer cloning involves the artificial production of offspring that is genetically identical to another organism, Whereas a pair of identical twins have been developed by the same fertilised egg and is not an artificial means of fertilisation. The technique involves transferring the nucleus from the cell of an adult into an egg cell that has had its nucleus removed. The egg is then implanted into the uterus of a female, where it can grow as a normal embryo.

Question 13

Which statement best explains the use of genetically engineered organisms?

A) Genetic engineering produces better specimens.
B) Genetic engineering will help humans survive better.
C) Genetically engineered organisms can improve agricultural production.
D) Genetically engineered organisms are useful in medicine.

Answer 13

C

Question 14

Which statement represents the best definition of a clone?

A) A clone is a collection of genetically identical organisms.
B) A clone is an exact copy of a different species.
C) A clone is an organism produced by genetic engineering.
D) A clone is a genetically modified organism.

Answer 14

C

Question 15

Outline two examples of ways in which gene technology can be used in medicine.

Answer 15

Includes:

-

Question 16

Outline two potential benefits to farmers of genetically modified crops and livestock.

Answer 16

Includes:

-

Question 17

Define artificial insemination, artificial pollination and cloning.

Answer 17

Artificial Insemination:
Artificial Pollination:
Cloning:

Question 18

For a named plant and a named animal that have been genetically modified, predict the potential impact of this on the genetic diversity of the species.

Answer 18

Includes:

-

Question 19

What is Neurospora?

Answer 19

Includes:

- Neurospora Crassa is a bread mould, a fungus with a haploid genome.

Question 20

How did Beadle and Tatum produce mutants?

Answer 20

Includes:

- Beadle and Tatum produced mutant forms of Neurospora by exposing the wild type to radiation.

Question 21

Describe the control in Beadle and Tatum’s experiment.

Answer 21

Includes:

- The control is the normal type which can be compared to the other forms to show differences.

Question 22

How was the Beadle and Tatum hypothesis modified?

Answer 22

Includes:

-

Question 23

What was the evidence which led to Beadle and Tatum’s ‘one gene one protein’ hypothesis?

A) Interbreeding different pea plants to form hybrids.
B) Showing the bacteria, Escherichia Coli, can be infected by viral DNA.
C) Growing bread mould, Neurospora Crassa, on different agar growth mediums.
D) Splicing RNA of the ciliated protozoan, Tetrahymena, using ribozomes.

Answer 23

C

Question 24

Name some diseases that are caused by transmission of pathogens through water supplies.

Answer 24

Includes:

-

Question 25

Sedimentation, coagulation, filtration, and disinfection are all used to purify water. Define these terms.

Answer 25

Sedimentation: Clumps of dirt and particles sink to the bottom of calm, still water to form sludge.
Coagulation: Aluminium sulfate is added to help sink flocs, and make sedimentation faster.
Filtration: Water is filtered, e.g. through sand beds, so that leaves, algae, dirt, sticks are trapped and the water is clean.
Disinfection: Involves the addition of chemicals for disinfection to destroy pathogens.

Question 26

Outline the events of the 1998 outbreak of Cryptospordium and Giardia in Sydney’s water supply.

Answer 26

Includes:
- Low levels of cryptosporidium and giardia were first detected in the water supply on 21 July. The levels were within acceptable health limits. In days following, much higher levels were recorded, and on 27 July the first “boil water” alert (in which residents were instructed to boil their tap water before use) was declared for the eastern Sydney central business district. On 29 July a “boil water” alert was issued for the south of Sydney Harbour and on 30 July a Sydney-wide “boil water” alert was issued.
The Sydney Water Corporation announced the water safe to drink again on 4 August.

Question 27

Describe the current procedures that Sydney Water uses to prevent any future outbreak of pathogens in Sydney’s water supply.

Answer 27

Includes:

-

Question 28

Evaluate the the contributions made by both Louis Pasteur and Robert Koch to our present understanding and possible prevention of infectious diseases.

Answer 28

Includes:

• Relate each scientist’s work to how we currently treat and manage disease in society today.
• Provide an overall judgement of how their research has affected health of society.
• Make reference to Koch Postulates.
• Make reference to Pasture’s Swan Neck experiment.
• Make reference to how Koch and Pasteur disproved the theory of spontaneous generation, with the germ theory of evolution.

Question 29

The most important innovation in Pasteur’s ‘swan neck flask’ experiment was:

A) The experiment could look for contamination without disturbing the experiment.
B) A glass barrier prevented contamination.
C) Fresh air could directly contact the medium.
D) Heating media prevented microbial growth.

Answer 29

C