Chp 11: Infectious Diseases in Humans Flashcards
parts of bacteria
cell wall
cell membrane
DNA
cytoplasm
plasmid
ribosomes
flagellum
how is bacteria’s nucleus different?
it does not have a membrane-bound nucleus
what are plasmids
see youtube
structure of virus
-protein coat
-genetic material (DNA/RNA)
what dna material does virus have
DNA or RNA
what dna material does bacterial have
DNA
what are the non-living characteristics of virus
- does not have cellular structure like cell membrane, cytoplasm or organelles
- it does not grow, move, feed, respire or excrete
what are the living characteristics of virus
it can reproduce
-only when it enters a living cell (host)
- host cells contains necessary materials for reproduction (like enzymes and organelles like ribosomes)
what causes influenza
influenza VIRUS
complications caused by influenza virus
pneumonia
how is influenza virus transmitted
by touching a surface which has influenza virus and touches their eyes, nose or mouth
what causes pneumococcal disease?
pneumococcus BACTERIA
[streptococcus pneumoniae]
what part of the body does pneumococcal disease affect?
attacks different parts of body
- middle ear infection
- lung infection (pneumonia)
- inflammation of membranes in brain and spinal cord
- infection of blood
how is it transmitted
through respiratory droplets
how does vaccine protect us from diseases
- contains an agent which represents pathogens
- prevents infectious disease by stimulating white blood cells to produce antibodies quickly when pathogens invade
(antibodies are proteins produced to destroy pathogens)
ANTIGENS TRIGGER the production of WHAT
antibodies
what is the PRODUCTION of ANTIBODIES triggered by
antigens
what are transmittable/infectious diseases caused by
pathogens
examples of pathogens
bacteria and virus
how are infectious diseases spread
- through droplets in the air
- by direct contact
- by contaminated food and water
what are the proteins on the surface of pathogens
virus and bacteria
what are viruses and bacteria
antigens
what is one property of antibodies
specific in action
how do WBC prepare to protect us for the future
some of the WBC remain in the blood stream. If in future the same pathogens enter our bloodstream, the WBC recognise and produce antibodies to destroy the pathogens before they infect our cells
what are antibiotics
drugs used to treat bacterial infections
how do antibiotics work?
- used to kill or inhibit the growth of bacteria
- work by interfering with the growth and metabolic activities of the bacteria
do antibiotics work against viruses/bacteria?
antibiotics do not work against viruses, only bacteria
how does antibiotic affect bacterial cell wall
- some antibiotics prevent the synthesis of bacterial cell walls. this weakens the cell wall and allows water to enter the cell via osmosis causing the cell to expand, burst and die
how does antibiotic affect the bacterial cell membrane
- it inhibits cell membrane function by breaking up the cell membrane. without cell membrane, the cell is unprotected from its environment and any substance can move into bacterial cell.
how does antibiotics affect bacterial ribosomes
antibiotics bind themselves to bacterial ribosomes and prevent them from taking part in protein synthesis. therefore, inhibiting cell growth
how does antibiotics affect the cytoplasm
bacteria require a vitamin called folic acid FOR GROWTH. antibiotics inhibit the enzyme needed for the synthesis of folic acid which inhibits cell growth.
why can antibiotics kill bacteria but not viruses
1) antibiotics work on cell walls, viruses do not have cell wall
2) antibiotics work in cell membranes, viruses do not have cell membranes
3) antibiotics work on ribosomes, viruses do not have ribosomes
what happens when you do not finish your antibiotics course
- 1) in a population of bacteria, there are bacteria with less and more sensitivity to antibiotics
2) when antibiotic is taken, more sensitive bacteria are killed, some less sensitive bacteria remain alive
3) if you stop your antibiotic course, the little bacteria left will multiply and infect our cells again
how does antibiotic resistance increase?
-when antibiotic courses are incomplete, some bacteria are left alive
- they will multiply and spread again
- overtime, subsequent generation of bacteria will become more resistant
how can we reduce antibiotic resistance
- do not misuse or overuse antibiotics
- complete the full course of antibiotics prescribed by the doc (to make sure all bacteria are killed)
- use antibiotics only when necessary
