bacteria as pathogens

Question 1

what happens if bacteria get into the blood

Answer 1

they can be carried all around system and cause systemic infection

Question 2

different ways bacteria make people ill

Answer 2

some because of how they invade and destroy host tissues
-most through toxins they make as by product of their metabolism
-toxins may incapacitate whole organism or just immune system

Question 3

how can toxins be classified

Answer 3

endotoxins
exotoxins

Question 4

chemical structure of endotoxins

Answer 4

lipopolysaccharides

Question 5

where do endotoxins come from

Answer 5

come from outer layer of cell wall of gram negative bacteria

Question 6

what acts as toxin in endotoxins

Answer 6

lipid part of polysaccharide that acts as toxin while polysaccharide stimulates immune system

Question 7

infection area of endotoxins

Answer 7

they effect around site of infection by the bacteria

Question 8

pathogenic effects of endotoxins

Answer 8

-fever
-vomiting
-diarrhoea

Question 9

examples of endotoxins

Answer 9

salmonella spp
-E.coli

Question 10

how do antibiotics release more endotoxins

Answer 10

when they destroy bacterial cells by lysis of cell wall endotoxins can be released because of lipopolysaccharide component of cell wall

Question 11

diseases caused by salmonella bacteria

Answer 11

salmonellosis gasreoenteritis

Question 12

how do salmonella bacteria act in diseases

Answer 12

invade lining of intestine and endotoxins cause inflammation
-cells no longer absorb water so faeces become liquid
-gut then goes into spasms of peristalsis that result in diarrhoea

Question 13

how is salmonella spread

Answer 13

by ingestion of good and water contaminated with infected faeces

Question 14

who do antibiotics work for when treating bacterial infections

Answer 14

young people
old people
people with compromised immune system

Question 15

what do antibiotics do to most people when taken to treat bacterial infections

Answer 15

just reduce symptoms allowing person to fell better but act as carrier for longer

Question 16

best way to deal with diseases caused by salmonella spp

Answer 16

avoid them by cooking meat all the way
-washing hands after dealing with raw meat
-wash hands after using toilet
-avoid drinking contaminated water

Question 17

s typhi

Answer 17

strain of salmonella spp that causes typhoid

Question 18

features of exotoxins

Answer 18

usually soluble proteins
-produced and releases into body by bacteria as they metabolise and reproduce in cells of their host

Question 19

how are exotoxins produced

Answer 19

by gram negative and positive

Question 20

effect of exotoxins on infection

Answer 20

effect can be more widespread than endotoxins as they act at sites distances from the infecting bacteria

Question 21

specific effects of exotoxins

Answer 21

-some damage cell membranes causing cell breakdown or internal bleeding
-some act as competitive inhibitors to neurotransmitters
-others directly poison cells

Question 22

example of deadly exotoxin caused disease

Answer 22

clostridium botulinum
-produces botulinum toxins
-most toxic natural substance known
-1mg of pure toxin could kill a million guinea pigs

Question 23

example of exotoxin strains

Answer 23

staphylococcus
-one third of us carry at some of then in normal skin and gut flora

Question 24

how to STP cause disease

Answer 24

if they get inside body tissues
-if normal skin flora is changed
-if the person has a compromised immune system due to another disease
-treatments such as chemo

Question 25

what type of bacteria are coccus

Answer 25

gram positive bacteria

Question 26

S aureus

Answer 26

causes skin infections such as styes, boils and impetigo

Question 27

what can coccus diseases be treated with

Answer 27

with antibiotics if they are diagnosed quickly but exotoxins they produce are powerful and can cause death rapidly

Question 28

how do bacterias invade host tissue

Answer 28

invade tissue and damage cells
-response of host organism to cell damage causes of symptoms to disease
-cell damage linked to production of exotoxins or presence of endotoxins in bacterial cell wall

Question 29

another example of an exotoxin

Answer 29

mycobacterium tuberculosis

Question 30

how is TB spread

Answer 30

by droplet infection
-crowded areas
sneezes coughs
-compromised immune systems more likely to catch it

Question 31

other source of infection

Answer 31

mycobacterium bovis
affects cattle
-people become infected drinking infected milk or living in close contact to cattle

Question 32

what does TB affect

Answer 32

respiratory system
-damaging and destroying immune system
-damages lung tissue

Question 33

TB symptoms

Answer 33

coughing up blood
weakness

Question 34

primary infection of TB

Answer 34

bacteria inhaled and invade cells of lungs and multiply slowly
-no symptoms
-if good immune system then localised response contained mass tissue

Question 35

tubercle

Answer 35

mass of tissue immune system makes up by killing containing dead bacteria and macrophages

Question 36

bacteria of mycobacterium TB that survive pass primary infection stage

Answer 36

-produce thick waxy outer layer that protects them from enzymes of macrophages
-with coating they stay in lungs until person weak immune system
-then active TB caused