Diseases Flashcards
Communicable disease
Can be passed from one organism to another, in animals
Often from one individual species to another but some BETWEEN species - vectors
What is a communicable disease?
Can be passed from one organism to another, in animals- often from one individual to other, in animals. Often from one individual of a species to another -but some BETWEEN species- vectors
Types of pathogen
Bacteria, Virus, Protoctista, Fungi
Bacteria
Prokyaryotes
Don’t have a membrane bound nucleus/organelles
Damage host by releasing waste products and toxins
Live in vascular tissues and causes BLACKENING and deaths of tissues
How are bacteria classified?
By their basic shape- rod, spherical, comma shaped, spiralled, corkscrew
By their cell walls-2 main types of bacteria cell have different structures - react differently to gram staining
Gram staining
Gram positive bacteria look blue-purple under light microscope e.g. MRSA
Gram negative bacteria- red e.g. gut bacteria E.coli
Type of cell wall affects how bacteria reacts to different antibiotics
Viruses
Genetic material surrounded by a coat of protein
Cannot reproduce without cells
0.02-0.3um in diameter
50 time smaller than an average bacterium
Viruses reproduce rapidly and evolve by developing adaptations to their host
How do viruses destroy cell
Invade living cells, where the genetic material of the virus takes over biochemistry f host cell t make more viruses
Protoctista
A group of eukaryotic organisms with a wide variety of feeding methods
Includes single celled organisms and cells groups into colonies
Enter host and feed on contents as they grow
Mauy need a vector
Parasitic - use animals as host
Fungi
Eukaryotic and multicellular
Yeasts that cause human iseases are single celled
Cant phosynthesise, digeest good EXTRACELLULARLY before absoribing teh nutrients
Many fungi are sprophytes =feed on dead and deayign matter
Parasitic
Fungal infections often affect the leaves of teh plant and stop them photosyntehsis - quickly killplant
Reproduce = millions of tiny spores
Netweork of fibre fialment called hyphae formin the mycellium
Damaging host tissue directly
VIRUSES- Take over cell metabolism
-The viral genetic material gets into the host cell and inserted into host DNA , Virus then uses host cell to make new viruses which burst out if cell
PROTOCTISTA -Take over cells and break them open as the new generation emerge, but they do not take over the genetic material of the cell. DIgESt and use cell contents as they reporduce e.g, malaria
FUNGI - Digest living cells and destroy them
Producing toxins which damage host tissue
BACTERIA- Produce toxins that posion or damage the host cell in some way, causign disease
- Somr damage the host cells by breakign down the cell memrbanes , sme inactivate enzymes and sme interfere with the gentic info so cellw ont divide
FUNGI - Some fungi produce toxins which affect the host cells and cause disease
Plant bacterial disease
RING ROT
RIng rot
Bacterial disease of potatoes , tomatoes and aubergines
Gram positive
Transmissin= direct contact, cotnaminated potato waste/water supply
EFFECT= Vascular tissues appear glassy and eater soaked. 80% of crops destroyed
SOLUTION- No cure, practice good hygeine and plant only classified seeds
Plant virus
Tobacco mosaic virus
TMV
Infects tobacco plants and 150 other specieis
e.g. tomatoes, peppers, cucumbers
Damages laves, flowers
Transmission- water and via plant and plant seeds
solution- resistant crop strains, good hygiene , regularly inspect plant and burn infected plants
Potato /tomato blight
protoctista Water rot, brown lesions Hyphae penetrate host cells Fungal spores by wind No cure
Tuberculosis
Bacterial disease of humans, cows, pigs
Effect -damages and destroys lung tissues and and suppresses the immune system so the body iks less’s able to fight off diseases
Global rise of HIV/AIDS has a large impact on tose suffering from Tb
Antibiotics
Types of pathogens
Fungi
Bacteria
Protoctista
Virus
Bacteria ?
Prokaryotic
DO NOT have a membrane bound nucleus/organelles
Damage host by releasing waste products and toxins
Live in vascular tissues and causes BLACKENING and deaths of tissues
How are bacteria classified
By basic shape - may be rod shaped, spherical, comma shaped, spiralled and corkscrew
By their cell walls- 2 main types of bacteria cell wall have different structures and so react differently to gram staining
Gram staining
Gram positive bacteria look blue- purple under light microscope e.g. MRSA
Gram negative- red e.g. Gut bateria E.coli
Type of cell wall affects how bacteria reats to different antibiotics
What are the modes of action for damaging that pathogens can take
Damaging host cells directly
Releasing toxins which damage host tissue
Damaging host tissues directly - Modes of action for pathogens
VIRUSES- Take over cell emtbolism
The viral genetic material gets into the host cell and inserted into host DNA. Virus then uses the host cll to make new viruses which burst out of cell-infect more
PROTOCTISTA- take over cells and break them open as the new generation emerge - dont take over the genetic material, digest and use
FUNGI- Digest living cells and destroying them
Producing toxins which damage host tissue- pathogens, modes of transport
BACTERIA- Produce toxins that poision or damage the host cell in some way, causing disease
- Some bacterial toxins that damage the host cell by breaking down the cell membranes, some damage enzymes, some interfere with the host cell genetic info so cells cant divide
FUNGI - Some fungi produce toxins which affect the host cells and cause disease
Black sigatoka
Banana disease
FUNGUS
Effect- brown rusty paint liek spots, attacks and destroys eaves- hypahe penetrate and digest cells turning them black
50% reduction in yield
SOLUTION- Resistant strains are beign developed
HIV/aids
Targets T helper cells in the immune system , gradually destroying
Humans and non human primates
Retrovirus with RNA as its genetic material, contain the enzyme reverse transcript 0 transcribes teh RNA to a single strand of DNA to produce single strand in host cell-
Bodily fluids
No vacccine or cure
Malaria
Protoctista plasmodium
Anopheles mosquito
2 hosts - people, and mosquito
Reproduce inside mosquito, when it feeds on blood - plasmodium is passed on
Invades blood cell, liver and brain
200 million get it a year
No vaccine, antimalarial tabs, drain stagnant water
Bacterial meningitis
Bacterial infections of the meniges of the brain
an spread into the rest of the body causing septicemia
Blotchy red and purpole rash
10% infected die
Sneezing transmission
Solution = antibiotics
Athletes foot
FUNGAL Form of ring worm Grows on and digests warm, moist in between toes Contact with infected Antifungal medicine
Influenza
Virus
Infects ciliated epithelial cells in gas exchange system
Kills them - leaving airways open to second infection
Severe seconadry bacterial infections on top of original
Classified by proteins on surfaces
Vaccine, rest
Ringworm
Fungi
Antifungal cream
grey white crusty areas
