6 Disease

Question 1

what does TB stand for?

Answer 1

mycobacterium tuberculosis

Question 2

what are the 10 components of bacteria:

Answer 2

1-flagellum
2-lipid granule
3-ribosome
4-pili
5-genetic material
6-slime capsule
7-cell wall
8-plasma membrane
9-cytoplasm
10-plasmid

Question 3

what are the 4 main components of viruses? (gerc)

Answer 3

Genetic material + packaged Enzyme
lipid Envelope
Receptor proteins
Capsid

Question 4

what type of genetic material can viruses have?

Answer 4

DNA or RNA

Question 5

what type of genetic material does bacteria have?

Answer 5

DNA ONLY

Question 6

what does bactericidal antibiotic mean?

Answer 6

the antibiotic will DESTROY bacteria

Question 7

what does bacteriostatic antibiotic mean?

Answer 7

inactivates bacteria by preventing reproduction

Question 8

how do bactericidal antibiotics work?

Answer 8

• inhibit cell wall synthesis → leads to lysis
• disrupt cell membrane so change in permeability = no bonds in cell wall = no growth

Question 9

how do bacteriostatic antibiotics work?

Answer 9

-inhibit nucleic acid synthesis- prevents cell division and the production of proteins

Question 10

how can bacteria spread resistance?

Answer 10

using tubes or pili it can directly share a copy of its DNA plasmid

Question 11

what do antibiotics treat?

Answer 11

bacterial and some fungal infections

Question 12

what is one way codes of practice have evolved?

Answer 12

• doctors less willingly hand out antibiotics to lessen the chances of resistant bacteria developing
• emphasising the importance of carrying out the full dose, the remaining 1% not killed could mutate and gain resistance

Question 13

what’s some improved hospital practice?

Answer 13

• constant washing of hands
• hand sanitiser
• masks

Question 14

what makes agar jelly a good culture medium?

Answer 14

contains food carbs/proteins

Question 15

is TB contagious?

Answer 15

YES

Question 16

how is TB easily spread?

Answer 16

droplets or airborne pathogens

Question 17

Why is it advantageous to TB bacteria to infect the upper part of the lung?

Answer 17

• TB is an aerobic bacterium which needs oxygen
• upper part has highest conc. of oxygen

Question 18

what is meant by granuloma?

Answer 18

a growth of tissue produced around an area of infection

Question 19

what are granulomas like in TB?

Answer 19

anaerobic and contain dead bacteria and macrophages

Question 20

name the process by which macrophages ingest bacteria.

Answer 20

phagocytosis

Question 21

what 3 conditions can weaken the immune system making you more susceptible to TB?

Answer 21

• HIV
• chemotherapy
• recent organ transplant

Question 22

explain how TB can evade the immune response.

Answer 22

• infect macrophages, other WBCs cannot detect them, antigens remain hidden
• cannot be broken down due to tough waxy cell wall
• lies dormant for many years

Question 23

state some symptoms of TB

Answer 23

• coughing blood
• short breath
• fever
• unexplained weight and appetite loss

Question 24

how can TB lead to secondary infections? death?

Answer 24

• macrophages are unavailable to destroy other pathogens
• slower response
• once in blood it can travel to other vital organs and spread

Question 25

why are some countries more prone to TB? 5 points

Answer 25

- poor sanitation - overcrowding - lack of vaccines - cost of antibiotic for the whole 6 months - larger HIV population → more TB

Question 26

why would a HIV infection increase risk of TB?

Answer 26

attacks immune system and T helper cells

Question 27

what organ is most commonly infected with TB?

Answer 27

Lungs

Question 28

outline the treatment for TB

Answer 28

- at least 3 diff antibiotics over 3-9 months - rest and healthy diet

Question 29

what does HIV stand for?

Answer 29

human immunodeficiency virus

Question 30

what does AIDS stand for?

Answer 30

acquired immune deficiency syndrome (final stage of HIV)

Question 31

what are the 6 components of HIV?

Answer 31

- gp 120 molecule (glycoprotein) - lipid bilayer - layer of viral proteins - capsid - 3 viral proteins - 2 RNA strand

Question 32

what are the 3 viral proteins of HIV? (rip)

Answer 32

- **r**everse transcriptase - **I**ntegrase - **p**rotease

Question 33

how does HIV replicate?

Answer 33

- HIV gp120 binds to CD4 receptor - viral RNA and proteins are down into cell - RNA reverse transcribed into DNA - Integrase inserts viral DNA into hosts DNA (latency period) - once translated and transcribed, protease modifies the proteins - viral genetic material and protein packaged in capsid - capsid exits to infect another cell

Question 34

explain the meaning of latency in replication of HIV.

Answer 34

Dna inserted into host cells chromosomes

Question 35

what does reverse transcriptase do?

Answer 35

produce DNA from viral RNA

Question 36

what does integrate do?

Answer 36

inserts viral DNA into host cell DNA

Question 37

what does protease do?

Answer 37

modifies proteins after transcription and translation

Question 38

how is HIV transmitted from person to person?

Answer 38

-semen, blood vaginal fluid via unprotected sex or sharing needles, breastfeeding

Question 39

what type of cells dies HIV infect?

Answer 39

T helper cells - with CD4 receptor

Question 40

what symptoms come from HIV?

Answer 40

flu like eg sweating, vomit, fever, sometimes none

Question 41

how can HIV lead to death?

Answer 41

- high HIV count but Loe T helper (bad as this is important in triggering an immune response) - susceptible to secondary disease eg cancer, TB