Health & Disease - Core B

Question 1

Define Health

Answer 1

A state of complete physical, mental, and social well-being, not merely the absence of disease or infirmity.

Question 2

Define Disease

Answer 2

A disorder of structure or function in a living organism that produces specific symptoms, affecting health.

Question 3

Causes of infectious diseases

Answer 3

Pathogens, ie.
- Bacteria (cholera, tb, strep throat)
- Virus (influenza, measles, chicken pox)
- Fungi (tinea, athletes foot)
- Parasites (tape worm, head lice)
- Protozoa (malaria, sleeping sickness)
- Prions (kuru, Creutzfeldt-Jakob Disease)

Question 4

Causes for non-infectious diseases

Answer 4

• genetic mutations (sickle cell, cystic fibrosis)
• environmental factors (heavy metal poisoning, cancer)
• lifestyle (scurvy, obesity, heart disease)

Question 5

What’s an infectious disease?

Answer 5

Caused by the spread of pathogens that have invaded the body - they can be transmitted between individuals.

Question 6

What’s a non-infectious disease?

Answer 6

Not caused by pathogens, caused by malfunctions in the body and cannot be transmitted between individuals.

Question 7

What’s a pathogen?

Answer 7

Micro-organisms that cause disease. When it invades the body, it grows and multiplies and secretes poisoning toxins which damage body tissues.

Question 8

Characteristics of bacteria

Answer 8

Single-celled organisms that can reproduce quickly. ie. (E. coli)

Question 9

Characteristics of virus

Answer 9

Non-living agents that require a host cell to replicate. ie. Influenza virus, HIV

Question 10

Characteristics of fungi

Answer 10

Thrive in damp environments; can be multi- or single-celled. ie. Candida albicans causing Thrush

Question 11

Characteristics of parasite

Answer 11

Live in or on a host and extract nutrients for survival. ie. tapeworm

Question 12

Characteristics of protozoa

Answer 12

Single-celled organisms, often parasitic in nature. ie. Giardia species

Question 13

Characteristics of prions

Answer 13

Misfolded proteins that cause degenerative brain diseases. ie. Creutzfeldt-Jakob Disease

Question 14

What do antibiotics do?

Answer 14

Kill or inhibit bacterial growth (e.g., penicillin for strep throat).

Question 15

What do antivirals do?

Answer 15

Target viruses by interfering with their replication (e.g., oseltamivir for influenza).

Question 16

Antifungals

Answer 16

Treat fungal infection by interfering with the fungal cell membranes (e.g., fluconazole for candidiasis).

Question 17

Why Don’t antibiotics Work for Viruses?

Answer 17

Viruses replicate within host cells, and antibiotics target bacterial structures, not host cells.

Question 18

What did the soap practical show?

Answer 18

Showed that soap and water effectively reduce bacterial presence compared to water alone or no washing - and sanitiser with alcohol is ineffective. Found the most bacteria on classroom door handles and desks, reinforcing the need for hygiene practices.

Question 19

Examples of Lifestyle for non-infectious disease

Answer 19

Obesity → Heart disease
Smoking → Lung cancer

Question 20

Examples of genetics for non-infectious disease

Answer 20

Inherited conditions like Cystic Fibrosis, Huntington’s disease.

Question 21

Examples of environmental factors for non-infectious disease

Answer 21

Pollution → Asthma
Asbestos exposure → Mesothelioma

Question 22

What are the human defence mechanisms (3)

Answer 22

First Line: Skin, mucus, saliva, and stomach acid prevent pathogen entry. They use enzymes, act as a physical barrier, trap pathogens, or flush them out

Second Line: (immune system) White blood cells (like phagocytes), inflammation, and fever to slow down pathogen replication.

Third Line: (immune system)
B cells that produce antibodies targeting specific pathogens.
T cells that destroy infected cells or regulate immune responses.
Memory cells that “remember” pathogens for faster responses during future infections.

Question 23

What’s active immunity?

Answer 23

Developed after exposure to a pathogen or vaccine, creating long-term memory.

Question 24

What’s passive immunity?

Answer 24

Antibodies are introduced from an external source, rather than being made by the individual’s immune system. Temporary protection through antibodies from another source (e.g., breast milk).

Question 25

Types of vaccines

Answer 25

Live-Attenuated Vaccines: contain weakened (attenuated) forms of the actual pathogen, which cannot cause severe disease in healthy individuals. ie. measles Inactivated Vaccines: Contain pathogens that have been killed or inactivated. ie. hepatitis A Subunit: use specific parts of the pathogen (like proteins or sugars) to trigger immunity. ie. hpv mRNA Vaccines: Use messenger RNA to instruct cells to produce a harmless piece of the pathogen, usually a protein, to provoke an immune response. ie. covid vaccines (Pfizer)

Question 26

How do vaccines work?

Answer 26

Introduce a harmless part of a pathogen to stimulate the immune system without causing disease. They are training your immune system to recognise and fight specific pathogens.

Question 27

6 Vaccines on the are on the Australian immunisation schedule for children.

Answer 27

- Measles - Mumps - Rubella - Polio - Hepatitis B - Whooping Cough

Question 28

What's Herd Immunity?

Answer 28

When 95% of the population is vaccinated, it protects those who can’t be vaccinated, because there are less people infected.

Question 29

Benefits of Vaccines

Answer 29

1. Prevents the spread of infectious diseases. 2. Protects vulnerable populations. 3. Reduces healthcare costs long-term.

Question 30

Risks of Vaccines

Answer 30

1. Side effects like soreness. 2. Rare allergic reactions. 3. Some people's immune systems are too weak to handle the vaccine

Question 31

Define Epidemic

Answer 31

Localised outbreak of a disease (e.g., Ebola outbreak in West Africa).

Question 32

Define Pandemic

Answer 32

Worldwide spread of a disease (e.g. COVID-19).

Question 33

Outline a recent pandemic and what is being done to control the issue

Answer 33

COVID-19 resulted in millions of deaths and significant disruptions to healthcare systems and economies. Control Measures: Mass vaccination, Social distancing, mask mandates, and hand hygiene. Ongoing Research: Studies continue to monitor variants and improve treatments.

Question 34

Outline a non-infectious and what is being done to control the issue

Answer 34

Skin cancer is one of the most common types of cancer, with melanoma being the most serious form. Australia has one of the highest rates in the world, because of high levels of UV radiation. Control Measures: Wearing hats, sunscreen, Regular dermatologist visits. Restrictions on tanning beds and improved workplace safety for outdoor workers. Research: Advances in immunotherapy and targeted treatments for melanoma

Question 35

Create a flow chart of what happens in the human body when pathogens enter the body

Answer 35

1. Pathogen Enters the Body - Through a cut, inhalation, ingestion, or other means. ⬇ 2. First Line of Defence (Barriers) - Physical barriers like skin and mucus block entry. - Chemical barriers like stomach acid, tears, or saliva kill or flush out pathogens. - If this fails, the pathogen progresses further. ⬇ 3. Second Line of Defence (Innate Immune System) - Inflammation: Increases blood flow to the area. - Phagocytosis: White blood cells (like macrophages) engulf and destroy pathogens. - Fever: Body temperature rises to slow pathogen growth. - If the pathogen persists, it triggers the next line of defence. ⬇ 4. Third Line of Defence (Adaptive Immune System) - T-cells recognize and attack the pathogen or infected cells. - B-cells produce antibodies that bind to and neutralize the pathogen. - Memory cells are created to ensure faster responses in future infections. ⬇ 5. Pathogen is Neutralised or Eliminated - The immune system clears the infection. ⬇ 6. Healing and Recovery Begin - Damaged tissues repair, and the immune system returns to a baseline state.