Lecture 1

Question 1

Describe microorganisms

Answer 1

too sm to clearly see w/ the unaided eye (microns to macroscopic)
relatively simple anatomy
lack highly differentiated cells, lack tissues
Types - fungi, bacteria, viruses, (prions)

Question 2

What are the types of microorganisms in order of decreasing complexity

Answer 2

fungi -> bacteria -> virus -> (prions)

Question 3

What is a prokaryote?

Answer 3

single celled organism lacking a true ucleus and membrane bound organelles
have cell walls (except for mycoplasma)

0.1-10um

Question 4

What is a eukaryote

Answer 4

Cells w/ a true nucleus
membrane bound organelles present
cells or higher organisms
can be single-celled or multicellular organisms

10-100 um

Question 5

Describe fungi

Answer 5

Kingdom fungi includes mould and yeast
unicellular organisms but can exist as complex multicellular structures
eukaryotic
can be both asexual or sexual repo cycles

Question 6

What are some examples of fungi?

Answer 6

bread mold, penicillum, mushrooms, ringworm

Question 7

Describe bacteria

Answer 7

Domain bacteria
ubiquitous and can live in extreme enviros
single celled
prokaryotic
majority have cell wall w/ peptidoglycan
lack a membrane-bound nucleus
asexual repro
majority req 1000x magnification to be seen

Question 8

What are acellular infectious agents?

Answer 8

Infection “particles”
are not cells
have the ability to replicate, but only when they have infected a cell
two types:
virus + prions

Question 9

What are virus?

Answer 9

composed of: genetic material, protein capsul, proteins + sugars to attach to host cells, lipic envelope layer
cannot replicate on their own
1000-100,000x smler than bacteria

Question 10

What is one of the lgest and most complex virus?

Answer 10

Influenza

Question 11

What is one of the smlest virus made up of a single strand of DNA?

Answer 11

Parvovirus (250 nucleotides) and a shell containing 2-4 diff proteins

Question 12

What are prions?

Answer 12

Discovered by stanley prusiner in 1982
infectious protein particle
causative agent of the spongiform encephalopathies - bovine spongiform encephalitis (mad cow), scrapies

Question 13

What is Koch’s Postulates?

Answer 13

1. Microorg must be present in every case of disease but absent from healthy individuals
2. Suspected microorg must be isolated + grown in a pure culture
3. The same disease must result when the isolated microorg is inoculated into a healthy host
4. the same microorg must be isolated again from the diseased host

to test if a disease was caused by a germ

Question 14

How does the binomial naming system work?

Answer 14

Genus followed by species
italicise (or underline) both the genus+species
genus is capitalized; species is always lowercase
Can refer to genus by “short form”

Ex. Escherichia coli
E. coli

if referring to geus in general, can refer to genus or generic species within genus

Staphylococcus spp.

Question 15

What is an etiological agent?

Answer 15

whatever causes the disease
can be a toxin, trauma, microorg

Question 16

What is the def of infection?

Answer 16

invasion and multiplication of organisms inside the body
usually causes injury
injury can be direct or indirect

Question 17

what is the def of infectious

Answer 17

capable of causing infection, capable of being transmitted by infection

Question 18

what is the def of infectivity

Answer 18

the ability to enter and replicate in a host

Question 19

what is the def of direct injury

Answer 19

when using in the context of an infection, refers to damage to tissues caused by the infectious organism
ex. toxins produced by the bacteria

Question 20

what is the def of indirect injury

Answer 20

when using in the context of an infection, refers to the damage to tissues caused by the immune system

Question 21

What is the def of host

Answer 21

an animal or plant on or in which a parasite or commensal organism lives
ex. in a case of a cold, cold virus has infected a human host

Question 22

what is the def of a host cell

Answer 22

a cell infected by a microorg, most commonly by a virus
in the case of a virus infection, host cell becomes site of virus replication

Question 23

What is the def of a pathogen?

Answer 23

a virus, bacteria or microorg that can cause disease

Question 24

what is the def of pathogenic

Answer 24

the ability to cause disease

Question 25

What is the def of pathogenic factor

Answer 25

What allows the pathogen to cause disease
ex. tetanus toxin, botulism toxin, endotoxin

Question 26

What is the def of pathogenicity?

Answer 26

measure of how much damage a pathogen is able to cause to a host

Question 27

what is the def of non-pathogenic

Answer 27

unable to cause diseae

Question 28

What is the def of virulence?

Answer 28

similar to pathogenicity, measure of a pathogens ability to overcome the body’s defences

Question 29

What is the def of virulence factors?

Answer 29

similar to pathogenic factors

Question 30

what is the def of normal flora?

Answer 30

normally present on the healthy host

Question 31

what is the def of ubiquitous

Answer 31

found everywhere

Question 32

What is the def of in vivo?

Answer 32

within the living body

Question 33

what is the def of invitro?

Answer 33

“within a glass”
outside the living body, usually referring to a test tube or petri dish

Question 34

what is the def of a culture?

Answer 34

the propagation of microorg or living tissues in special growth media?