Wk 9- Infectious Microbial Agents

What are the 4 main microorganism? • F- • P- • B- • V-

Microorganism classification: Saprophages: live off dead and d? matter Symbionts: live together with - Commensals: live with and host and cause no harm Parasites: live on/in another o? and cause p? conditions

Fungi: E- Uni cellular = ? Multicellular = ? Yeasts live in - environments ? are visible mycelium Infection = myc?

Fungi mycoses: Types of infections • Su? : outermost surface layer skin • C- : colonise in hair/skin/ nails • Sub C-: entry via skin trauma • Sy? : via spores, most dangerous

Protozoa: Unicellular E- Very mobile Engulf small microorganisms - environments Ingested in contaminated food and drink (g-) Carried by insects

Bacteria: No nucleus= P- No m- bound o- External f- / pili for mobility Bacteria in every habitat on earth

Pathogenic bacteria: E coli Fast replication =1 to 1 - in 8 hours Inhabits i- Cause gastro-

Periodontitis: bacteria Porphyromonas g? Bacterial anti? and immune system Immune cells release ROS( R? Oxygen sp?) super oxide and hydrogen peroxide to attack bacteria ROS attacks host tissue and attracts more - cells

Viruses: Sub microscopic entities They are ultra cellular p- , NOT cells No n? o? or cytoplasm Replicate - host

Virus / virion structure: Viral DNA/RNA encapsulated pr? shell = capsid Viral e? enable insertion into host DNA Outer layer from host cell l? bilayer Use hosts biochemical replication mechanism

Viral Haemagglutinins and Neuraminidase: Haemagglutinins: Anti? glycoproteins on viral s? Binds virus to host cells 1- different H identified

Viral H and N: Neuraminidase: E- on viral surface Acts on infected cells surface to release viral progency - different N’s

Effects of viral infection: L? = cell rupturing , cell swell, functions diminish Syncytia= cells form together into large multi n? mass

Mutations to viral DNA/RNA: Results in different viral s? Difficult for treatment