6B

Question 1

What is non specific response

Answer 1

Same regardless of the pathogen that invades the body

Question 2

What’s is specific

Answer 2

Specific to particular pathogen

Able to recognise specific pathogen due to the presence of antigens on their cell surface

Question 3

What steps of inflammation
Non specific

Answer 3

Mast cells respond to tissue damage by secreting histamine

This causes blood vessel to dilate leading to redness reducing the reproduction rate of pathogen

Histamine makes the cell forming the walls of the capillaries separate slightly thus making the Capillary walls become more permeable allowing fluids to enter the tissue and create swelling
—> releasing plasma contains leukocytes out forcing antibodies out of the capillaries
Disabling pathogens

The antibodies disable the pathogens and macrophages and neutrophils destroy them by phagocytosis

Phagocytes leave the blood and enter the tissue to engulf foreign particles

Question 4

What do interons do

Answer 4

They inhibit the production of viral proteins preventing the virus from replication

They activate white blood cells involved with the specific immune response to destroy infected cells

They in case the non specific immune respe

Question 5

How does fevers

Why does the Hypothalamus reset the body temperature higher
Non specific

Answer 5

Many pathogens reproduce quickly at 37c can’t below so higher temperatures will reduce their ability to effectively reproduce

Specific immune response function better at higher temperature making combat against the infection more successful

Question 6

How is fever beneficial

Answer 6

Patient will start to sweat to cool the body down releasing fluid and electrolyte

If not replaced this could lead to severe dehydration it can cause enzyme to denature resulting permanent tissue damage

Question 7

Phagocytosis

Answer 7

1)Chemicals released by pathogens as well as chemicals released by the body cells under attack

2)They move towards pathogen and recognise the antigens on the surface of the pathogen as Beng non-self

3) the cell surface membrane of phagocytes extend out and around the pathogen, engulfing it and trapping the pathogen within a phagocytes vacuole
—> endocytosis

4) enzyme are released into the phagocytic vacuole when lysosome fuse with it

5) these digestive enzyme, which includes lysosomes digest the pathogens

6)after digesting the pathogen , the phagocytes will present the antigens of the pathogen on its cell surface membrane

Question 8

Where is T cell produced from

Answer 8

Produced in the bone marrow and activated in the thymus gland

Question 9

What’s is T killer cell used for

Answer 9

Produce chemicals to destroy infected cells

Question 10

What is helper T cell usedfor

Answer 10

Activate plasma cell to produce “ antigens - specific” antibodies and secrete opsonin to label pathogens for phagocytosis

Question 11

T memory cell

Question 12

Where is B cell produced and what it produces

Answer 12

Produced in the bone marrow

These cells have globular receptor proteins sued in producing immunoglobulin (antibodies

Question 13

What does B effector cells do

Answer 13

Divide to form plasma clones

Question 14

What does plasma cell

Answer 14

Produce antigen specific antibodies

Question 15

B memory cell

Answer 15

Provide immunological memory (secondary response)

Question 16

What does humoral response

Answer 16

Production of antibodies

Question 17

Humoral response

Answer 17

T helper activation stage

Effector stage

Question 18

T helper activation stage

Answer 18

1)Bacterium with antigens on surface

2) bacterium engulfed by a macrophages

3)macrophages present the antigens from the bacterium on major his to compatibility complexes (MHCs) it becomes an antigen presenting cell (APC)

4) a macrophages APC binds to T helper cell. Once the T cell is activated, it divides to form T memory cells and active T helper cell

Question 19

Effector stage

Answer 19

1)Bacterium with antigens on surface

2) antigens binds to B a cell with complementary receptor. The B cell engulfs the bacterium by endocytosis and enzyme break it down to leave antigen fragments

Question 20

Effector step 3

Answer 20

B cells becomes an APC

Question 21

Effector step 4

Answer 21

An activated T helper cell with a complementary receptor binds to the APC. It produces cytokines that stimuli the B cell

Question 22

Effector stage 5

Answer 22

The B cell divides to give B memory and B effector cells

Question 23

Effector stage 6

Answer 23

B effector cells differentiate into plasma cell

Plasma cells secrete antibodies these bind to the antigens on other similar pathogens identifying them so they are easier to destroy

Question 24

What is agglutination

Answer 24

Binding to antigens on pathogens to make them stick together

Question 25

What is opsonisation

Answer 25

Antibodies act as an opsonin making pathogens more easily recognised by phagocytosis

Question 26

What neutralisation

Answer 26

Binding to bacterial toxins to reduce their effect

Question 27

Cell mediated response step 1

Answer 27

A bacterium infects a host cell

Question 28

Cell mediated response step 2

Answer 28

Host cell present the antigens on MHCs and become an APC

Question 29

Cell mediated response step 3

Answer 29

T killer cell with complementary receptor binds to the APC Cytokines from activated T helper cells

Question 30

Cell mediated response step 5

Answer 30

Stimulated by cytokines from the T helper cell the T killer cell divides and differentiate to form two clones one of the active T killer cells and one of T killer memory cells

Question 31

Cell mediated response step 6

Answer 31

The active T killer cells bind to infected cells presenting antigens on MHCs

Question 32

Cell mediated response step 7

Answer 32

The T killer cells releases chemicals causes lysis in the infected cell as pores form in the membrane the infected cell dies

Question 33

What happens in primary response

Answer 33

Number of T and B cells with correct membrane receptors are Low To be activated and divide and differential into different cell types It can take several days before plasma cells develops and are able to start producing antibodies against antigen —> infected person will experience symptoms Both B and T cells produce memory cells during the primary respe which will remain in the blood after infection is over

Question 34

Secondary response

Answer 34

Faster and stronger than the primary response Memory cells are present in larger quantities tha the mature lymphocytes at the start of the primary response so the correct memory cell are able to detect an antigen activate divide by mitosis and differentiate much more quickly Antibodies are produced more quickly and are in larger quantities

Question 35

Natural active immunity

Answer 35

When your body comes into contact with a foreign antigen, causing the immune system to be activated to produce antibodies against the pathogen to destroy it

Question 36

What is natural passive immunity

Answer 36

Temporary immunity given from the mother to the fetus , through the transfer of pro formed antibodies through placenta or the mother milk and this last until the fetus immune system become active

Question 37

Artificial passive immunity

Answer 37

Where antibodies from one individual are extracted and injected in another , which prevents development of the disease , but not give long term immunity

Question 38

Artificial active immunity

Answer 38

Small amount of a safe form the pathogen are used to grant immunity - injection of detoxified form of toxin -inactivated viruses or dead bacteria -attenuated pathogens -using fragments of outer coat of viruses

Question 39

Eradication of disease

Answer 39

Disease not found in either people animals or anywhere in the environment

Question 40

Elimination of disease

Answer 40

Disease disappears but remains in animals, the environment or mild infection so immunisation must continue regardless of the number of cases

Question 41

Here immunity

Answer 41

Large portion of the population is vaccinated against a disease, so that it becomes very difficult for the disease to keep affecting who can be vaccinated is vaccinated, so that those who cannot be vaccinated don’t catch the disease. It is important to provide herd immunity when there is a serious outbreak of a disease

Question 42

Drugs against micro-organism

Answer 42

Antibiotics destroy microorganisms or prevent them from reproducing, and along with immunisation this has cured many diseases. Antibiotics work based on selective toxicity, by interfering with the chemistry or metabolism of the bacteria without affecting the human host

Question 43

What is bacteriostatic

Answer 43

Inhibit the growth of bacteria

Question 44

Define Bactericidal

Answer 44

Kills bacteria

Question 45

What are the 2 actions of bacteriostatic

Answer 45

Interrupting metabolic pathways to block nucleic acid or viral nutrients synthesis Protein synthesis inhibition or prevention of transcription and translation of microbial genes

Question 46

What are Bactericidal 3 actions

Answer 46

1) prevent formation of cross linking cell walls to kill bacteria by lysis 2) damage the cell membrane so water moves in to metabolite or move out killing the bacteria 3) stop bacterial DNA winding into rings so that it can no longer fit inside the cell

Question 47

Factors that affect the antibiotics

Answer 47

- concentration of drug around infected area -local pH -whether the pathogen or host cell destroy the antibiotics -susceptibility of pathogens to the antibiotics used

Question 48

Dose of drug

Answer 48

If the standard dose of drug destroy the pathogens and cures the disease, the pathogen is said to be sensitive to the antibiotic.

Question 49

Drug resistant

Answer 49

1) a group of bacteria include genetically resistant ones, are exposed to an antibiotic 2) most of the sensitive bacteria die 3) the genetically resistant bacteria starts multiplying 4) eventually the resistant strain replaces the strain affected by the antibiotics

Question 50

How to reduce selection pressure

Answer 50

- use antibiotics only when strictly necessary -making sure people complete their antibiotics course -using as few different antibiotics as possible and introduce new antibiotics when possible

Question 51

MRSA

Answer 51

S.aureus can be the skin or inside nasal passage without affecting, once inside the body it can have negative effect Treated with methicillin but has now develop3d a resistance High dosage with narrow of drugs

Question 52

Clastrrdium difficile

Answer 52

This is an anaerobic bacteria which can be present in the body and not cause harm as they’re their number are limited

Question 53

Controlling the use of antibiotics

Answer 53

Antibiotics should be used carefully only when necessary —> full course should be completed If not completed the immune system will not be able to destroy all the bacteria, and so they can infect other people and grow resistant

Question 54

Hand washing

Answer 54

Wash their hands with alcohol based gels and chlorine disinfectant to destroy any pathogens. In addition they should wear appropriate clothing to avoid spreading pathogens

Question 55

Isolation of patients

Answer 55

HAI infected patients need to be isolated in high level of hygiene and disinfect rooms as to prevent the spread of infection

Question 56

Prevention of infection coming into the hospital

Answer 56

Patients carrying communicable disease need to be treated of them first before they are treated of the main infection As to not spread infection. Moreover unwell people should not visit patients and when visiting visitors should maintain a high level of hygiene

Question 57

Monitoring levels of HAI

Answer 57

Measuring and reporting is important as it is attracts attention so that more effort are put to solve the problem

Question 58

Explain how a mutation in the genome could lead to the host suffering from influenza more than once

Answer 58

On the first infection the host immune system makes antibodies and memory cells against the virus antigens If the same antigens are detected a secondary response is rapid and prevents symptoms developing A mutation will alter the shape of the antigens The host memory cells will no longer recognise the antigens

Question 59

Suggest why this might lead to secondary infection by bacteria

Answer 59

Ciliated cells move mucus up the respiratory tract Infected cells die and the mucus stops moving Bacteria are caught in the mucus Ence ideal conditions and reproduce quickly Bacteria experi

Question 60

Decomposition in nature

Question 61

Conditions for recycling nutrients

Answer 61

Warm and moist —> higher temperature —> greater enzyme activity —> not too high it going to denature Moist - makes dissolving easier -prevent microorganisms from completely drying Plenty of oxygen -decays faster as decomposed respire faster

Question 62

Factors that affect the time of death fat level

Answer 62

Body fat slows down cooling because it acts as an insulator, and so a fatter person will cool slower than the thinner one

Question 63

Factors that affect the time of death mode of death

Answer 63

Someone who died in a cold area will cool faster than in a warm area

Question 64

Factors that affect the time of death surrounding temperature

Answer 64

Someone who died in a cold area will cool faster than in a warm area

Question 65

Factors that affect the time of death surface area ; volume

Answer 65

Smaller people cool faster as diffusion is more sufficient

Question 66

Factors that affect the time of death clothing

Answer 66

Clothes and covering insulate the body and so it cools slower

Question 67

Rigor mortis

Question 68

What are vaccine

Answer 68

Contains antigens whichare put into the body for active artificial Vaccines contain dead or weaken pathogen less harmful strain

Question 69

How vaccination work

Answer 69

Vaccination produce long term immunity as they cause memory cell to be created The immune system recognise the antigens when re-encountered and produce antibodies in a faster, stronger secant response