B6b: Harmful Microorganisms

Despite giving a range of useful products, some microorganisms are dangerous to humans. Each year millions of deaths are directly caused by bacteria and viruses. The work of Lister, Pasteur and Fleming illustrates how uncertainties in scientific knowledge change over time and the role of the scientific community in validating these changes. 

HideShow resource information
How can you prevent antibiotic resistance?
Avoid over-use of antibiotics and to complete the prescribed dose. This helps to slow down the development of other strains of resistant bacteria.
1 of 26
How are some strains of bacteria becoming resistant to antibiotics?
By natural selection 1.in a large population of bacteria,there may be some cells that aren't affected by antibiotica 2.these resistant cells survive&reproduce,while non-resistant cells can't 3.eventually the population consists of resistant bacteria
2 of 26
Do antibiotics work against viruses?
No.
3 of 26
How are antiseptics used in the control of disease?
Antiseptics are substances that can be applied to the skin to kill or stop the growth of microorganisms, including bacteria.
4 of 26
How are antibiotics used in the control of disease?
Antibiotics are substances that kill bacteria or stop their growth.
5 of 26
What did Louis Paster discover?
Pasteur showed food decay is caused by microorganisms in the air.Before this discovery,scientists believed it was air itself that caused decay.Pasteur proposed the ‘germ theory of disease’ - diseases are caused by microorganisms that enter the body
6 of 26
What did Alexander Fleming discover?
Scottish scientist Fleming discovered the first antibiotic - penicillin – in 1928. Since then, many other antibiotics have been discovered or developed.
7 of 26
What did Joseph Lister discover?
He developed use of carbolic acid(phenol)as an antiseptic.He used it to sterilise surgical instruments&area around operations.This reduced rate of infection in operations.However,carbolic acid causes skin burns&safer antiseptics are used today
8 of 26
What is a very dangerous bacteria? and why?
MRSA (methicillin-resistant Staphylococcus aureus’) - it's dangerous because it is resistant to most antibiotics.
9 of 26
What four reasons explain why natural disasters cause a rapid spread of diseases.
Damage to: sewage pipes and water supplies, electrical supplies causing rapid food decay, displacement of people and disruption to health services.
10 of 26
Describe the four stages of an infectious disease.
1. Pathogen enters body 2. Incubation period during which the pathogen grows and/or reproduces rapidly 3. toxins (poisonous chemicals) are released into the body by the pathogens 4. symptoms appear - eg a fever
11 of 26
How can the transmission of a infectious disease be prevented?
The transmission of infectious diseases can be prevented if the pathogens are unable to enter the body. The type of prevention depends on how the pathogen gets in.
12 of 26
Name three ways infectious diseases can be spread.
Food and water, contact and airborne droplets.
13 of 26
Describe what infectious disease can be transmitted through food and water, and how to help prevent this.
Pathogens can spread via contaminated food or water. The body has some natural defences against this, including stomach acid that kills bacteria. Cooking food thoroughly and sterilising drinking water can help to limit the spread of pathogens.
14 of 26
Describe what infectious disease can be transmitted through contact, and how to help prevent this.
Pathogens - such as those that cause STIs (sexually transmitted infections) - can be transmitted from person to person by close contact. The spread of STIs can be reduced by using condoms.
15 of 26
Describe what infectious disease can be transmitted through airborne droplets.
Pathogens - such as the viruses that cause colds and ‘flu - can spread via airborne droplets. When an infected person sneezes, droplets containing viruses pass into the air and may be breathed in by other people.
16 of 26
Describe how you can prevent the spread of the disease through airborne droplets.
The body has natural defences against this, including mucus in the airways to trap pathogens and cilia to move the mucus out of the airways. Face masks can help to limit the spread of pathogens through airborne droplets.
17 of 26
What are some microorganisms?
Pathogens.
18 of 26
In which four ways can pathogens enter the body - give examples.
Nose (airborne microorganisms), Mouth (contaminated food and water), Reproductive organs (contact) and Skin (insect bites, cuts, infected needles)
19 of 26
Name three micro-organisms.
Fungi, bacteria and viruses.
20 of 26
What diseases can bacteria cause?(2)
Cholera and food poisoning .
21 of 26
What disease can fungi cause?
Athlete's foot.
22 of 26
What diseases can viruses cause?(2)
Influenza and chickenpox.
23 of 26
What substance can control harmful bacteria?
Antibiotics.
24 of 26
What can happen between the relationship of bacteria and antibiotics?
Bacteria can become resistant to antibiotics.
25 of 26
Which two diseases can be a major problem following a natural disaster. (Give two examples)
Cholera and Food poisoning - e.g earthquake or volcanic eruption.
26 of 26

Other cards in this set

Card 2

Front

How are some strains of bacteria becoming resistant to antibiotics?

Back

By natural selection 1.in a large population of bacteria,there may be some cells that aren't affected by antibiotica 2.these resistant cells survive&reproduce,while non-resistant cells can't 3.eventually the population consists of resistant bacteria

Card 3

Front

Do antibiotics work against viruses?

Back

Preview of the front of card 3

Card 4

Front

How are antiseptics used in the control of disease?

Back

Preview of the front of card 4

Card 5

Front

How are antibiotics used in the control of disease?

Back

Preview of the front of card 5
View more cards

Comments

helloRiley

Very helpful, thank you!

Similar Biology resources:

See all Biology resources »See all Microbes and disease resources »