Health, Diease, Defence Mechanisms And Treatments

Question 1

Define communicable disease

Answer 1

One that can be passed from one organism to another

Question 2

Define non-communicable disease

Answer 2

One that is not passed from one organism to another.

Question 3

What type of disease is HIV? How is it spread and prevented?

Answer 3

Virus
Spread by exchange of bodily fluids during sex and infected blood
Prevented by using a condom, as will drug addicts not sharing needles
Currently controlled by drugs

Question 4

What type of disease is colds/flu and how is it spread and prevented?

Answer 4

Virus
Spread by airborne (droplet infection)
Flu vaccination for targeted groups

Question 5

What type of disease is HPV how is it spread and prevented?

Answer 5

Virus
Sexual contact
HPV vaccination given to 12-13 year old girls to protect against developing cervical cancer

Question 6

What type of disease is salmonella? How is it spread and prevented?

Answer 6

Bacterium
Contaminated food
Always cook food thoroughly; not mixing cooked and uncooked foods can control spread
Treatment with antibiotics

Question 7

What type of diesel is TB, how is it spread and prevented?

Answer 7

Bacterium, droplet airborne infection
BCG vaccination, if contracted treated with drugs including antibiotics

Question 8

What type of disease is chlamydia? How is it spread and prevented?

Answer 8

Bacterium
Sexual contact
Using a condom will reduce risk of infection
Treatment with antibiotics

Question 9

What type of disease is athletes foot? How is it spread and prevented?

Answer 9

Fungus
Spread through contact
Reduce risks of infection by avoiding direct contact where spores are likely to be present, e,g wear flip flops in changing rooms/swimming pools.

Question 10

What type of disease is potato blight? How is it spread and prevented?

Answer 10

Fungus
Spores spread in air from plant to plant, particularly in warm humid conditions.
Crop rotation and spraying plants with fungicide.

Question 11

Name 3 ways the body stops microorganisms entering it

Answer 11

Skin- barrier that stops microorganisms entering body
Mucous membranes- thin membranes in the nose and respiratory system that trap and expel microorganisms
Clotting- closes wounds quickly to form a barrier that stops microorganisms gaining energy (also stops blood loss)

Question 12

What is a lymphocyte?

Answer 12

A type of white blood cell that produces antibodies

Question 13

What is an antigen?

Answer 13

A distinctive marker on a microorganism that leads to the body producing specific antibodies

Question 14

What is an antibody?

Answer 14

A structure produced by lymphocytes that has a complimentary shape shape and can attract to antigens on a particular microorganism.

Question 15

What is a memory lymphocyte?

Answer 15

A special type of lymphocyte that can remain in the body for many years and produce antibodies quickly when required.

Question 16

What is the role of white blood cells?

Answer 16

Lymphocytes produce antibodies, these are complimentary in shape to the antigens and clump them together. They can then be destroyed or engulfed by phagocytes.

Question 17

What is a phagocyte?

Answer 17

A type of white blood cell that destroys microorganisms by engulfing and digesting them. This process is called phagocytosis.

Question 18

What is the primary response?

Answer 18

Antibody numbers being high enough to provide immunity

Question 19

What is the secondary response

Answer 19

The body producing memory lymphocytes that remain in the body for many years.

Question 20

Define immunity

Answer 20

Freedom from disease

Question 21

Define active immunity

Answer 21

The type of immunity produced when the body produces antibodies.

Question 22

Define passive immunity

Answer 22

The type of immunity produced by injecting antibodies

Question 23

What are differences between active and passive immunity?

Answer 23

Active is slow acting whereas passive is fast acting
Active lasts a long time whereas passive only lasts a short period of time.

Question 24

Define vaccination

Answer 24

The injection of dead or modified pathogens with the purpose of raising antibody and memory lymphocyte levels in the blood.

Question 25

What is a booster vaccination?

Answer 25

One we get to make sure that we remain immune for a reasonable period of time. The is known as a follow up booster.

Question 26

What defence against disease do plants have?

Answer 26

Waxy cuticles- prevents microorganisms entering leaves Thick cell walls- surround cells Chemical- procure anti microbial chemicals harmful to infectious microorganisms. E.g in mint

Question 27

Who discovered the first antibiotic and what was it called

Answer 27

Alexander Fleming discovered penicillin in 1928

Question 28

How did Fleming discover penicillin?

Answer 28

Observed that bacteria could not grow close to the fungus Concluded that something was spreading from the fungus and killing bacteria.

Question 29

Who isolated the chemical responsible and was able to mass produce it?

Answer 29

Florey and Chain. They were able to isolate the chemical responsible. This chemical was the commercially produced as penicillin. The microbes that make the penicillin are grown in large biodigesters or fermenters that create perfect conditions for fungal growth.

Question 30

What happens in preclinical trials?

Answer 30

Stage 1 in vitro testing. Tests on living cells and tissues in laboratory. Drugs are tested to see if they are effective and if it does harm. Allows testing before use on living organisms. An initial trial and error process. Stage 2- animal testing, tests to see how they work on a whole organism.

Question 31

What are the benefits of animal testing?

Answer 31

Avoids testing on humans Can check for side effects in living organisms

Question 32

What are the disadvantages of testing on animals?

Answer 32

Animals are different from humans, so the drug may react differently in humans. Raises ethical issues.

Question 33

Define preclinical trials

Answer 33

The stages involved in testing drugs and medicines that occur before testing on human volunteers.

Question 34

What happens in clinical trials

Answer 34

Testing on a small number of healthy human volunteers and then patients. Testing for how effective the drug is and finding optimum dosage and possible side effects. Peer review then happens

Question 35

Define clinical trials

Answer 35

The stages involved in testing drugs and medicines that use healthy human volunteers and volunteer patients.

Question 36

What does peer review involve?

Answer 36

Involves new research and new discoveries being scrutinised by other scientists of at least equal standing to investigator. Provides detailed feedback and suggest refinements where appropriate.

Question 37

Define antibiotic

Answer 37

A chemical produced by fungi that kills bacteria

Question 38

What is antibiotic resistance?

Answer 38

Bacteria can evolve so that antibiotics mo longer have an effect. Bacteria can mutate Their DNA can change and develop new properties, this can make them resistant to antibiotics

Question 39

How are superbugs formed

Answer 39

Overuse of antibiotics

Question 40

What procedures are there to reduce the incidence of superbugs?

Answer 40

Not overusing antibiotics when not needed. Increased hygiene in hospitals. E.g staff and and visitors washing hands or hand gel Isolating patients infected with superbugs.

Question 41

How is the aseptic technique carried out?

Answer 41

1.Pass the metal loop through the flame of the Bunsen Bruner 2. Allow the metal loop to cool off 3. Remove the lid of the culture bottle and glide loop over the surface of agar. (Inoculation) 4. Replace lid of culture bottle to prevent contamination. Sweep neck of bottle through flame to destroy any airborne microorganisms. 5. Spread microbes on agar in petri dish. Important to hold lid at angle to reduce the chance of unwanted microbes from air entering dish. 6. Metal loop is heated to high temperature again to ensure any microorganisms remaining on loop is destroyed. 7. Petri dish should be taped and heated at 25°C. 8. Important to work near Bunsen burner during transfer to create an upward current of air, moving microorganisms away 9. When investigation is complete it it important to clean all surfaces.