4.1 Communicable Disease Flashcards
1
Q
what is a pathogen?
A
a microorganism that causes disease
2
Q
how do pathogens survive?
A
- live in hosts
- take nutrition from their host and cause damage at the same time
3
Q
what is bacteria?
A
prokaryotic organisms that are able to reproduce rapidly
4
Q
how does bacteria cause disease?
A
animals: damage cells and release toxic waste products
plants: bacteria live in vascular tissue and cause blackening and death of these tissues
5
Q
tuberculosis
A
- caused by mycobacterium tuberculosis
- spreads by air droplets from infected to uninfected host
- destroys lung tissue and other body tissues
6
Q
meningitis
A
- (caused by neisseria meninitidis)
- infects the meninges, membrane that surrounds the brain and spinal cord, they become swollen and may cause damge to the brain and nerves
7
Q
ring rot
A
- (caused by clavibacter michiganensis)
- cause ring of decay in vascular tissue
- leaves wilt
8
Q
how dies viruses cause disease?
A
- invade cells and take over genetic machinery and other organelles in the cell
- cause cell to produce more copies of the virus
- host cell bursts releasing lots of new viruses which infect healthy cells
9
Q
HIV
A
human immunodeficiency virus
- attacks cells of the immune system resulting in death from opportunistic disease such as tuberculosis
10
Q
Influenza
A
- constantly change and mutate
- attack respiratory system
- muscle pains
11
Q
tobacco mosaic virus
A
- cause mottling and discoloration of leaves
- doesn’t kill plants
12
Q
how does fungi cause disease in animals?
A
- often live in the skin of host, its hyphae grow under the skin and form a mycelium (mass of hyphae)
- fungus sends out specialised reproductive hyphae to the surface of the skin it cause redness and irritation
13
Q
athlete’s foot
A
- (caused by trichophyton rubrum)
- grows under skin of foot
- fungi
14
Q
ringworm
A
growth of fungus in skin with spore cases erupting through skin to cause a rash
15
Q
how does fungi cause disease in plants?
A
- plant fungi live in vascular tissue in order to gain nutrients
- hyphae sends out extracellular enzymes to digest the surrounding tissue which cause decay
- leaves become mottled, curl up, shrivel and die
- fruit and tubers turn black and decay
