Host Invasion by Microorganisms Flashcards

Host invasion

Question	Answer	Article
By what three routes can pathogens enter the body?	Contact Aerosol Orofecal	Link to Answer Article

Viruses

Question	Answer	Article
Naked viruses contain only...?	RNA/DNA and protein coat	Link to Answer Article
Name three functions of viral structural proteins	Protection of the genome Attachment to host cell Fusion of envelope to host cell membrane	Link to Answer Article
Name the two main innate defences against viral infection	Interferon Natural killer cells	Link to Answer Article
Upon viral infection, which antibody isotype is increased at mucosal surfaces?	IgA	Link to Answer Article
What do antibodies stop free virus particles from doing?	Binding to host cell, entering and uncoating	Link to Answer Article
By what mechanism is complement able to damage the virion envelope?	Virolysis	Link to Answer Article
When coupled with antibodies, what mechanisms does complement aid in immune defence?	Blocking the virus receptor Lysis of infected cells Opsonisation of free particles or infected cells	Link to Answer Article
What are the main cytokines CD4+ T cells release to recruit macrophages?	IFN-γ TNF	Link to Answer Article

Bacteria

Question	Answer	Article
Describe three ways prokaryotic DNA differs from eukaryotic DNA	Few repeated sequences Most of the DNA is transcibed No intervening sequences within structural genes	Link to Answer Article
These surface components allow bacteria to move around	Flagella	Link to Answer Article
Bacteria with an outer layer of lipopolysaccharide are classed as...	Gram-negative	Link to Answer Article
Bacteria with a round shape are classed as...	Cocci	Link to Answer Article
Bacteria with a long shape are classed as...	Rods or bacilli	Link to Answer Article
What are the four rules summarising the cause and effect relationship between bacteria and infection?	Koch's postulates	Link to Answer Article
What is the condition, characterised by excessive cytokine production, that is caused by bacterial components such as LPS?	Endotoxin shock	Link to Answer Article
By what mechanism do most bacteria replicate?	Binary fission	Link to Answer Article
By what three mechanisms can bacteria transfer DNA?	Transformation Transduction Conjugation	Link to Answer Article

Parasites

Question	Answer	Article
Do protozoa have a eukaryotic or prokaryotic cell structure	Eukaryotic	Link to Answer Article
What are the two main groups of helminth parasite?	Nematodes Platyhelminthes	Link to Answer Article
What is the main cell type that mediates the destruction of larger parasites?	Eosinophils	Link to Answer Article
What T cell subtype is required to fight intracellular protozoa	Th1	Link to Answer Article
What T cell subtype is required to fight intestinal worms?	Th2	Link to Answer Article
How do antibodies defend against parasitic infection?	Directly damaging protozoa Activating complement Blocking attachment to host cells Enhancing macrophage phagocytosis Antibody-dependent cell-mediated cytotoxicity	Link to Answer Article