The Search For Better Health
HSC Biology Teacher Workshop
Monday, 25th September, 2006
Nicole Sherry
Ambarvale High School
Course Requirements
Biology Syllabus p.10
The HSC course incorporates the study of:
a) the core, which constitutes 90 indicative hours and includes:
• Maintaining a Balance (30 indicative hours)
• Blueprint of Life (30 indicative hours)
• The Search for Better Health (30 indicative hours)

b) ONE option, which constitutes 30 indicative hours and may comprise any one of the
following:
• Communication
• Biotechnology
• Genetics: The Code Broken?
• The Human Story
• Biochemistry
Scope & Sequence
Topic
Homework
Syllabus
Reference
Lesson
Pre-reading
1.1
H pp 336-338
What is a healthy organism
Q p339
1a,b,c
1.2
H pp 340-343
Prac 9.4.1: Identifying
microorganisms
Write up practical
2a,b,c,d
Continued
Write up practical
1.3
1.4
H pp 346-347
Prac 9.4.2: Treatment of drinking
water
Answers to practical
questions, Q p347348
2e
1.5
H pp 349-351
Prac 9.4.3: Pasteur Experiment
Write up practical
3a,d
1.6
H p 360
Prac 9.4.4 Malaria
Q p353
3e
1.7
H p 362
Prac 9.4.6:Antibiotics (P.M Activity
7.9)
Answer questions to
P.M
3c,g
Register
Practical Hours
Biology Syllabus p. 9

Practical experiences are an essential component of both the
Preliminary and HSC courses. Students will complete 80 indicative
hours of practical/field work during both the Preliminary and HSC
courses with no less than 35 indicative hours of practical
experiences in the HSC course. Practical experiences must include at
least one open-ended investigation integrating skill and knowledge
outcomes in both the Preliminary and HSC courses.

We need to include at least 10 hours practical experiences in this unit.
Practical Register
Practical
No.
Title
Syllabus outcome
No. Hours
9.4.1
Identify microbes in food or in water
2d
1
9.4.2
Treatment of Drinking Water
2e
1
9.4.3
Pasteur’s Experiment
3d
1
9.4.4
Malaria
3e
1
9.4.5
Research an Infectious Disease
3f
2
9.4.6
Antiobiotic Resistance
3g
1
9.4.10
Plant Diseases
7c
1
TOTAL
12hours
Date
completed
1. What is a healthy organism?

Discuss the difficulties in defining the terms ‘health’ and ‘disease’
- definition for health
- definition for disease
- difficulties associated with these definitions

Outline how the function of genes, mitosis, cell differentiation and
specialisation assist in the maintenance of health.

Use available evidence to analyse the links between gene expression
and maintenance and repair of body tissues.
2. Cleanliness in food, water &
personal hygiene.

distinguish between infectious and non-infectious disease
- definition for infectious
- definition for non-infectious
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explain why cleanliness in food, water and personal hygiene practices
assist in control of disease

identify the conditions under which an organism is described as a
pathogen
Practical Activity

2d. identify data sources, plan and choose equipment or
resources to perform a first-hand investigation to
identify microbes in food or in water

Which outcomes from 9.1 Biology skills can be met during
this experiment?
9.1 Biology Skills

During the practical you can meet outcomes 9.1 Biology
Skills:
11.3 choose equipment or resources by:
a) identifying and/or setting up the most appropriate
equipment or combination of equipment needed to
undertake the investigation
1. Using agar plates to culture bacteria and fungi. Placing
food or water samples on the agar and incubating for a
couple of days.
2. Moistening a piece of bread in a petri dish and leaving in a
warm location if you do not have an incubator.
Biology Skills
11.3 b) carrying out a risk assessment of intended
experimental procedures and identifying and addressing
potential hazards
Risk Assessment:
Activity:
Growing micro-organisms
Risk:
micro-organisms may be harmful.
Precautions:
Seal the petri dish with sticky tape and clearly label the date and what the sample is.
After the experiment the micro-organisms will need to be destroyed before discarding if
using plastic petri dishes. If using glass petri dishes they will need to be sterilised before
reusing.
9.1 Biology Skills
12.1 perform first-hand investigations by:
c)disposing carefully and safely of any waste
materials produced during the investigation
d) identifying and using safe work practices
during investigations
2d. Treatment of Drinking Water

Gather, process and analyse information from
secondary sources to
- Describe ways in which drinking water can be treated
and use available evidence to
- Explain how these methods reduce the risk of infection
from pathogens.
Secondary Sources
Sydney Catchment Authority
http://www.sca.nsw.gov.au
They will be releasing an on-line activity on their
website – “Water Quality: HSC Chemistry” in
December 2006 (if you don’t already have the
CD)

Sydney Water
http://www.sydneywater.com.au


Water Made Clear: A consumers guide to accompany
the Australian Drinking water Guidelines 2004.
Activity: Treatment of Drinking
Water

Scan through “Water Made Clear” and
complete the table on the front.
3. Pasteur & Koch

3a. describe the contribution of Pasteur and Koch to our
understanding of infectious diseases
3b. distinguish between:
– prions
– viruses
– bacteria
– protozoans
– fungi
– macro-parasites
and name one example of a disease caused by each
type of pathogen
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Practical Activity

3d. perform an investigation to model Pasteur’s
experiment to identify the role of microbes in decay
from Surfing Biology
9.1 Biology Skills
11.2 plan first-hand investigations to:
a)
demonstrate the use of the terms ‘dependent’ and
‘independent’ to describe variables involved in the
investigation
Turn to Prac 9.4.3 – Pasteur’s Experiment & complete
Independent Variable:
(what we are manipulating) air can re-enter/not re-enter
Dependent variable:
(what we are measuring) presence of microbes, decay
9.1 Biology Skills
b) identify variables that need to be kept constant, develop
strategies to ensure that these variables are kept constant
and demonstrate the use of a control
Variables that need to be kept constant:
Amount of water, amount of heating, amount of broth.

Use of a control:
Leave one flask untreated
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Exam Questions

Question 27 (8 marks)
Evaluate the contributions made by both Louis Pasteur and
Robert Koch to our present understanding of the causes
and possible prevention of infectious diseases.
Evaluate:
Make a judgement based on criteria

What things should be included in this for an 8 mark
answer?
For the full 8 marks students are
required to:

Describe the work of Koch and Pasteur

Relate these to our present understanding of both the cause
and possible methods of prevention of disease caused by
micro-organisms.

Include a judgement of the impact of Pasteur and Koch’s
work
2002 HSC Notes from the Marking Centre Biology
From the markers:

This question was well answered. Most candidates were able to
describe Pasteur’s experiment and Koch's postulates.

Candidates were also able to evaluate, but many wrote more than
required and went beyond the space suggested in the answer booklet.
(a full page of 25 lines was given)

There was a small number of candidates who found it difficult to relate
the work of these scientists to modern practices. This was particularly
so for Koch.

A small number of candidates did not discuss the scientists separately.

The best responses included a judgement about the scientists' work as
part of their evaluation.
Infectious Disease

-
3f. identify data sources, gather process and analyse
information from secondary sources to describe one
named infectious disease in terms of its:
cause
transmission
host response
major symptoms
treatment
prevention
control
Exam Question
2005 HSC exam
Question 19 (4 marks)
During your study of Biology you have been required to gather and
analyse information on an infectious disease.
Fill in the table below for ONE infectious disease.
Name of the disease ___________________________________

Feature
Cause
Symptom
Treatment
Prevention
Description
4. Immune Response
a. identify defence barriers to prevent entry of pathogens in humans:
- skin
- mucous membranes
- cilia
- chemical barriers
- other body secretions
b. identify antigens as molecules that trigger the immune response
c. explain why organ transplants should trigger an immune response
d. identify defence adaptations, including:
- inflammation response
- phagocytosis
- lymph system
- cell death to seal off pathogen
Immune Response

Animated information about the immune system,
phagocytosis and lymph nodes is available at:
http://health.howstuffworks.com/adam-200095.htm
5. MacFarlane Burnet
a. identify the components of the immune
response:
- antibodies
- T cells
- B cells
Non-Specific Immunity
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The best action against micro-organisms is to prevent their entry into the body
altogether
This first line of defence against infection takes place at the body surfaces.
Skin - dry, waterproof surface that limits bacterial growth and prevents the
entry of other pathogens.
Mucous membranes & cilia
- mucus secreted by the cells lining your respiratory tract traps
bacteria which are then swept up to the back of the throat by the
action of cilia which line much of the tract.
- the mucus may be swallowed, blown, coughed or sneezed out.
Chemical Barriers
- acidity of the stomach
Other body secretions
- tears & saliva contain lysozyme which causes bacteria to lyse or burst.
- glands in skin secrete fatty acids and sweat contains salt, both of
which inhibit bacteria.
Components of the Immune System
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Bone marrow, the soft tissue in the hollow
centre of bones produces stem cells that
become each type of blood cell.
Lymphoid cells either mature in the
- bone marrow to become –B lymphocytes (B
cells) or
- thymus to become – T lymphocytes (T cells)
Monocytes, macrophages, and neutrophils are
often referred to collectively as "phagocytes."
These scavenger cells engulf and destroy some
invading particles, and clean up the remains of
others that have been destroyed by T-cells or Bcells.
Lymphocytes can travel in the blood vessels or
in the lymphatic vessels.
Cells are exchanged between blood and
lymphatic vessels.
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The organs of the immune system are
positioned throughout the body.
They are called lymphoid organs
because they are home to
lymphocytes.
Lymphatic system monitors the body
for invading microbes.
Lymphatic vessels carry lymph, a
clear fluid.
Lymph Nodes are found along the
lymphatic vessels, with clusters in the
neck, armpits, abdomen and groin.
Removal of lymph nodes: Breast
cancer cells which break off from the
tumor frequently travel through the
lymph fluid to the lymph nodes
where they get trapped.
Immune Cells
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Immune system stockpiles a
huge arsenal of cells.
Some immune cells take on all
comers, while others are trained
on highly specific targets.
To work effectively they all
work cooperatively.
Sometimes immune cells
communicate by direct physical
contact,
Sometimes by releasing
chemical messengers.
Inflammation Response
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Arterioles in the area around a cut dilate, resulting in an
increased blood supply to the area.
The blood carries phagocytes to the area.
Phagocytes that arrive early release chemicals such as
histamine that attract more phagocytes to the infection.
The pathogen is killed and engulfed by the phagocytes,
material that has leaked from the capillaries will form a
clot around the infection and prevent its spread.
Pus is formed from dead white blood cells and other cell
debris.
Eventually the pus and other dead or damaged cells are
reabsorbed by other cells of the body or released from the
skin.
T Lymphocytes (T-Cells)
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Viruses, parasites and bacteria that
invade the body are composed of
cells.
On the surface of each cell are
genetic markers called "antigens."
The immune system knows which
antigens belong in a person's body
and which do not.
When "helper" T-cells spot a
foreign antigen in the body, they
stimulate the production of
"killer" T-cells, which engulf and
destroy the invading cell.
"Suppressor" T-cells shut down
the immune system attack once the
foreign cell is destroyed.
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Helper T-cells can also order the second
type of lymphocytes-B-cells- into
action.
Helper T-cells point out foreign
antigens to the B-cells which, in turn,
replicate rapidly to produce a large
number of plasma cells which produce
a Y-shaped protein called an
“immunoglobulin" or "antibody."
The antibody zeroes in on the antigen
and attaches to the surface of the
invading cell.
The antibody then summons the
''complement system"-a group of
proteins circulating in the bloodstreamto surround the cell and dissolve a hole
in it.
This process is called cell lysis.
Antibodies
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Over the course of a lifetime,
millions of antibodies are
produced by B-cells.
The immunoglobulins of each B
cell have a specific structure
and recognise only one kind of
antigen.
Once an antibody has been
produced, it circulates through
the body for many years,
making the body "immune" to
further attacks by that particular
antigen.
Some of the B cells produced
differentiate into B-memory
cells.
Plasma cells only last a couple
of days.
Memory cells can survive for
years or for life.
Organ Transplants

5d. outline the reasons for the suppression of
the immune response in organ transplant
patients

ABC Catalyst – Transplant Hope
New Scientist – Boldest Cut (29 May 04)

Vaccination Programs

5c. outline the way in which vaccinations prevent
infection
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5e. process, analyse and present information from
secondary sources to evaluate the effectiveness of
vaccination programs in preventing the spread and
occurrence of once common diseases, including
smallpox, diphtheria and polio
6. Epidemiology

6a. identify and describe the main features of
epidemiology using lung cancer as an example

6c. gather, process and analyse information to
identify the cause and effect relationship of
smoking and lung cancer
Non-Infectious Diseases
6b. identify causes of non-infectious disease using an
example from each of the following categories:
- inherited diseases
- nutritional deficiencies
- environmental diseases


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6d. identify data sources, plan and perform a first-hand
investigation or gather information from secondary sources
to analyse and present information about the
occurrence,
symptoms,
cause,
treatment/management of a named non-infectious disease
7. Quarantine

7a. discuss the role of quarantine in preventing the
spread of disease and plants and animals into
Australia or across regions of Australia

7d. process and analyse information from
secondary sources to evaluate the effectiveness of
quarantine in preventing the spread of plant and
animal disease into Australia or across regions of
Australia
www.aqis.gov.au
ABC Catalyst – AQIS


7b. explain how ONE of the following strategies
has controlled and/or prevented disease:
- public health programs
- pesticides
- genetic engineering to produce disease-resistant
plants and animals


7e. gather and process information and use
available evidence to discuss the changing
methods of dealing with plant and animal diseases,
including the shift in emphasis from treatment and
control to management or prevention of disease

Thankyou

nicolesherry@education.nsw.gov.au