Infection and Immunity Flashcards
(59 cards)
What 6 things make individuals more susceptible to particular infections?
- Weakened immune system
- Poor nutrition
- Poor living conditions
- No access to health care
- Genetic disposition
- Lifestyle
What is an infection?
- The colonisation of a pathogen microbe on/in a susceptible host with associated dysfunction or damage.
What is the outcome of infection influenced by?
- The host’s immune system
- The affected body systems
- The drugs used
What is a pathogen?
- A bacterium, virus or other micro-organism that can cause disease.
What is the use of Gram stain reactions?
- To allow the detection and classification of most bacteria.
Why does gram negative stain red?
- As the iodine complex does not remain in the bacterium, as the cell wall isn’t thick enough to retain it.
- It is drawn out by the methanol/acetone and reacts to form a red colour.
Why are Gram positive bacteria stained blue?
- As the iodine complex remains in the cell
- The methanol/acetone cannot withdraw the iodine complex due to the thickness of the cell walls so it remains blue
Name the characteristics of Eukaryotes.
- No cell wall
- No envelope
- No capsid
- Membrane bound organelles
- DNA & RNA
- No pili or flagella
- No reverse transcriptase.
Name the characteristics of bacteria.
- Peptidoglycan or lipopolysaccharide cell wall
- No capsid
- No membrane bound organelles
- No nucleus only circular DNA
- DNA & RNA
- Pili and flagella
- No reverse transcriptase
Name the characteristics of Viruses.
- Can be enveloped
- No organelles
- Can have capsids
- DNA OR RNA
- No pili or flagella
- Can have reverse transcriptase.
- Needs the support of a cell to multiply
What are the two main groups of prokaryotes?
- Archea
- Bacteria
What are the two main groups of eukaryotes?
- Fungi
- Protozoa
What type of ribosomes do prokaryotes and eukaryotes contain?
- 70s
- 80s
What are viroids and prions?
- Infectious agents that appear to only consist of nucleic acid (Viroids) and protein (Prions)
What is a reservoir?
- Any habitat in which an infection agent can multiply
What is a source?
- A readily available form of an infectious agent
Give 5 modes of transport for an infectious agent into the host.
- Ingestion
- Inhalation
- Sexual contact
- Physical contact
- Innoculataion
What is a carriage?
- The passage taken by the micro-organisms
What is normal flora?
- Non-pathogenic bacteria that’s naturally found in our bodies.
What does commensal mean?
- Relationship in which one species derives benefit and the other is unaffected.
Staphylococcus aureus.
- Gram positive
- Food poisoning
- Toxic shock syndrome
- Abscesses
- If in blood stream: Endocarditis & osteomyelitis
Streptococcus pyogenes
- Gram positive
- Necrotising fasciitis
Group B Streptococci
- Gram positive
- Neonatal Sepsis
- Meningitis
Streptococcus pneumoniae
- Gram positive
- Pneumonia
