Microbes And Defence Against Disease

Question 1

How does body defend itself from infections?

Answer 1

Physical barriers eg skin, saliva and non-specific defences to prevent infection
Action of lymphocytes (white blood cells)

Question 2

What do phagocytes do?

Answer 2

Responsible for ‘mopping up’ infected cells + pathogens that have entered the body
Ingest + digest microbes (phagocytosis)

Question 3

4 steps of action of phagocytes

Answer 3

1) detection
2) migration
3) bacteria become engulfed
4) digestion

Question 4

Communicable diseases

Answer 4

Can be transmitted from one person to another

Question 5

Non-communicable diseases

Answer 5

Cannot be transmitted from one person to another

Question 6

Examples of communicable diseases

Answer 6

Measles, mumps, rubella, malaroa

Question 7

Examples of non-communicable diseases

Answer 7

Cancer, heart attack, diabetes, asthma

Question 8

Microbes

Answer 8

Very small living things that can only be seen clearly with a microscope

Question 9

Pathogens

Answer 9

Microorganisms that cause disease

Question 10

3 types of microbes

Answer 10

Viruses, bacteria, fungi

Question 11

Structure of viruses

Answer 11

Head capsul (contains dna) with a long tail with an end plate attatched

Question 12

Dangers of viruses

Answer 12

Cause many diseases including flu, chicken pox, mumps and aids. Flu virus can change into many different forms meaning you can’t be immune to it.

Question 13

Viruses uses

Answer 13

Genetic engineering

Question 14

Outbreak

Answer 14

Sudden rise in number of cases of a disease. May occur on community or affect several countries. May last for days/weeks/years

Question 15

Epidemic

Answer 15

Occurs when an infectious disease spread rapidly to many people

Question 16

Pandemic

Answer 16

Global disease outbreak. Affects wider geographical area than epidemic. Infects greater number of people. Caused by a new virus. Humans usually have little to no immunity against it. Creates social disruption, economic loss.

Question 17

What is SARS

Answer 17

severe acute respiratory syndrome

Question 18

Antibiotics

Answer 18

Group of chemicals that stop bacteria growth.

Question 19

What are vaccines? How can they help in long term?

Answer 19

Introduce antigens into body, which imitate an infection + primes the immune system to respond. Therefore they are good in long term as the immune system knows how to respond and plans.

Question 20

Superbugs

Answer 20

Bacteria resistant to certain antibiotics

Question 21

Antibiotic resistance

Answer 21

1) there are a lot of germs + a few are resistant to antibiotics
2) when antibiotics kill bacteria causing illness, they also kill good bacteria protecting the body from infection.
3) the antibiotic-resistant bacteria grow + take over
4) some bacteria are their antibiotic resistance to other bacteria, causing more problems

Question 22

How are superbugs formed

Answer 22

Caused by the misuse of antibiotics.
When antibiotics are overused or misused, the bacteria that have caused the disease in question are overexposed and produce mutations in attempt to survive

Question 23

Bacteria structure

Answer 23

Cocci are spherical in shape, bacilli are rod shaped, spriochetes are spiralled. Some may have a long filament called flagellum attatched which allows them to move

Question 24

Bacteria dangers

Answer 24

Cause many illnesses, mrsa, salmonella and tuberculosis. Cause food to go off

Question 25

Bacteria uses

Answer 25

Productions of yoghurt, treating sewage, genetic engineering

Question 26

Fungi structure

Answer 26

Spore case + a network of threads forming a structure called mycelium

Question 27

Fungi dangers

Answer 27

Responsible for athletes’ foot infection, ringworm + thrush

Question 28

Fungi uses

Answer 28

Spoil food e,g bread mould.
Yeast (fungus) used in baking + brewing industries.
Used in cheese industry

Question 29

How are pathogens spread?

Answer 29

Airborne, direct contact, indirect contact, water, vector (any organism that can spread a disease)