Bugs In The System Flashcards
What causes infection?
Viruses, bacteria, protozoa, parasites, insects
What is infection?
Invasion of a host organism by disease causing agents, their multiplication and reaction of host cell
Why do some people get certain infections?
From friends or famoly Poor hygeine Poor diet Airborne Weakened immune system Genetic lredisposition
What influences the outcome of infection?
Diet Health of individual Available treatments Hygeine Timely diagnosis and treatment
What are the shapes of bacteria?
Staphylococci- ball of beads
Streptococci - caterpillar
Backlli - rods
Diplococci - two
Describe bacteria structure
Peptidogylgan cell wall, circular dna/rna
Describe virus structure
Can be enveloped, have capsid, no organelles, dna/rna, no reverse transcriptase
How does bram staining work?
+(blue) or -(red) depending on cell wall
+vely charged crystal violet binds to -ve cell components
Iodine forms a karbe molecular complex witn crystal violet
Acetone or methanol extract the complexes through the gram negative cell eall
A red dye used to stain the now unstained gram -ve wall
How does acid fast work?
Allow us to detect bacterial causes of tb and leprosy that cant be detected by gram staining
As mycoplasmas dont have a cell wall
Define pathogen
Disease causing organism (bacterium, virus,other)
Define non pathogen
Doesnt cause disease
Explain the significance of genome composition for classification and detection of viruses
Rna viruses more likely to mutate as rna less stable
Explain the significance of envolope for classification and detection of viruses
Viruses with envolope cant survive if holes in envolope - easy to sterilise
Explain the significance of replication strategy for classification and detection of viruses
Rna viruses can use reverse transcriptase (hiv)
Dna viruses use cell machinery (hpv)
Some viruses carry their own replication enzymes
Describe some dna enveloped viruses
Hepatitis b - inflamed liver
Herpes - oral genital wall
Smallpox
