2.8 Disease, Defence and treatment (new)

Question 1

What is the function of a CELL WALL?

Answer 1

Protects + maintains shape

Question 2

What is the function of a CELL MEMBRANE?

Answer 2

Controls substances entering and leaving the cell

Question 3

What is the function of CYSTOPLASM?

Answer 3

Chemical reactions take place here

Question 4

What is the function of a CHROMOSOME?

Answer 4

Contains DNA

Question 5

What is the function of a SLIME CAPSULE?

Answer 5

Prevent bacteria drying out / Allows bacteria to stick together

Question 6

What is the function of a FLAGELLA?

Answer 6

Allows movement

Question 7

What is the function of PLASMID?

Answer 7

Small ring of DNA

Question 8

What MICRO - Organisms cause disease?

Answer 8

Pathogens

Question 9

Two examples of harmless bacteria?

Answer 9

• bacteria is in yogurt

- yeast in wine / beer

Question 10

Four examples of pathogens

Answer 10

• bacteria , virus, protists, fungi

Question 11

What is the causative agent of AIDS?

Answer 11

H.I.V (human immunodeficiency virus)

Question 12

How does AIDS affect a person?

Answer 12

• Infects lymphocytes

- leads to a lack of immunity to other infections

Question 13

How can AIDS be prevented?

Answer 13

Condom or disposable gloves

Question 14

What is the causative agent of Chlamydia?

Answer 14

Chlamydia trachmatis (bacteria)

Question 15

How does chlamydia affect an infected person

Answer 15

• infertility
• conjunctivitis
• lung problems in babies

Question 16

How can Chlamydia be prevented?

Answer 16

By using condoms

Question 17

What is the causative agent of Malaria?

Answer 17

Plasmodium (protist)

Question 18

How does Malaria affect a person?

Answer 18

• destroys red blood cells

- causing fever

Question 19

How do you prevent the spread of Malaria?

Answer 19

• killing mosquitos

- vaccines

Question 20

How does the body defence itself from disease?

Answer 20

• skin forming a barrier against micro-organisms
• blood clots to seal wounds
• phagocytes IN THE BLOOD ingesting micro-organisms
• lymphocytes producing antibodies and antitoxins

Question 21

What is an antigen?

Answer 21

• They are Protein molecules on cell membranes

Question 22

How do LYMPHOCYTES kill microbes?

Answer 22

• A lymphocytes recognises the antigen of an invading organism
• The antigen on the foreign cell CAUSES lymphocyte to MULTIPLY into clone cells
• then they SECRETE a lot of antibodies SPECIFIC to the antigen into the BLOODSTREAM
• The antibodies attach to the antigens on the microbes
• kill them for them or allow them to be engulfed by pathogens.

Question 23

What is the function of antibodies?

Answer 23

• the antibodies attach to the antigens on the microbes

- to KILL them or allow them to be engulfed by phagocytes

Question 24

How does a vaccine produce memory cells?

Answer 24

the vaccine causes the IMMUNE SYSTEM to produce COMPLEMANTARY antibodies

• The antibodies target the antigen and ATTACH THEMSELVES to it in order to create memory cells.
• These will quickly respond to the antigen if it is encountered again

Question 25

What does a vaccine contain?

Answer 25

- contains antigens derived from a diseased causing organism

Question 26

How do you have immunity after a vaccine?

Answer 26

- (After an antigen is encountered) memory cells REMAIN in the body - Produced QUICKLY , LARGER numbers of antibodies if the same antigen is encountered again - (hopefully destroying microbes BEFORE SYMPTOMS are felt) THIS IS IMMUNITY

Question 27

How were antibiotics ( Inc. Penicillin) produced?

Answer 27

- produced by living organisms ( fungi)

Question 28

How were antibiotics ( Inc. Penicillin) produced?

Answer 28

- produced by living organisms ( fungi)

Question 29

How do antibiotics cure bacterial infections?

Answer 29

- by KILLING bacteria or preventing their growth

Question 30

How do some bacteria (MRSA) become resistant to antibiotics?

Answer 30

over use of antibiotics

Question 31

How do you control MRSA?

Answer 31

- doctors prescribe antibiotics APPROPRIATELY - patients should always complete the full course of antibiotics - the agricultural use of antibiotics should be restricted

Question 32

How can you make sure new drugs are safe?

Answer 32

By testing EXTINSIVELY, at a LARGE SCALE and RIGUROUSLY.

Question 33

What do all drugs have?

Answer 33

Side effects

Question 34

3 Arguments FOR animal testing?

Answer 34

- helps researchers to find drugs and treatments - Improves human health - helps ensure safety of drugs

Question 35

3 Arguments AGAINST animal testing?

Answer 35

- Animals are killed or kept in captivity - it is very expensive - some substances tested may never be used for anything useful

Question 36

What is the process of developing new medicines?

Answer 36

- tested using computer models and skin cells grown using human stem cells in the laboratory. - tested on animals - tested on healthy volunteers to check that they are safe.

Question 37

What are 4 uses of monoclonal antibodies?

Answer 37

• diagnosis of diseases including Chlamydia and HIV • tissue typing for transplants • supporting chemotherapy for cancers - Pregnancy testing

Question 38

How are MONOCLONAL antibodies produced?

Answer 38

1-An antigen is injected into a mouse. 2-The mouse NATURALLY produces lymphocytes, which produce antibodies SPECIFIC to the antigen. 3- Spleen cells are fused with human cancerous white blood cells (MYELOMA CELLS) to form hybridoma cells which DIVIDE INDEFINITELY. 5-These hybridoma cells DIVIDE and produce MILLIONS of monoclonal antibodies SPECIFIC to the original antigen.