types of pathogens Flashcards
1
Q
what is a virus?
A
- an extremely small infectious agent
- consists of a protein sheath
- non cellular
2
Q
what is the structure of a virus?
A
- Contains ssRNA or dsDNA
- protein coat to protect nucleic acids
- Envelop made from a lipid bilayer studded with glycoproteins
- Proteins and enzymes
3
Q
how do viruses infect?
A
- they cannot reproduce by themselves
- DNA or RNA induces the host cell to manufacture new virus particles which then leave the cell and infect new
4
Q
what treatments are used for viruses?
A
- vaccines
- antivirals
5
Q
what is bacteria?
A
- single cell living organisms
- found in large numbers, everywhere
- unicellular
- prokaryotic
- spherical, rod, curved
6
Q
how do bacteria infect?
A
Once in the body, FIMBRIE enables bacteria to:
- attach to mucous membranes
- concentrate its attack on nearby tissues of the body
Bacteria release toxins (ENZYMES) that:
- digest the connective tissue of the host, allowing the spread of infection
- alter certain chemical reactions in cells so normal cell function is disrupted or the cell dies
- cause the blood to clot in small blood vessels
- damage to blood vessel walls, leading to leakage and a decrease in blood pressure
7
Q
what is a treatment for bacteria?
A
- improved sanitary conditions
- antibiotics
8
Q
what are the 4 types of bacteria?
A
cocci
baccilli
spirilla
vibrio
9
Q
describe cocci bacteria
A
sperical cells
- may occur singly, in pairs, in clusters or in chains
10
Q
describe bacilli bacteria
A
rod-shaped cells
- may have flagella for movement
11
Q
describe spirilla bacteria
A
twisted cells
12
Q
describe vibrio bacteria
A
curved rods often shaped like a comma
