Bacteria Flashcards

1
Q

two types of cells

A

eukaryotic cell and prokaryotic cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

three domains of life

A

eukarya, archaea, bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

prokaryotes

A
  • are microscopic organisms that contain no nucleus
  • they include the bacteria and archaea
  • prokaryotes are the most abundant and diverse organisms on earth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

archaea

A
  • no known pathogens
  • some archaea live in extreme environments and are called extremophiles
  • extreme halophiles = high saline environments
  • extreme thermophiles = hot environments
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

general features of a bacterial cell

A
  • lack nucleus but have nucleoid region
    prokaryotes - have small genomes
    - one big ring in nucleoid region = chromosome
    - smaller rings = plasmids
  • ribosomes are smaller and have a different makeup than the ribosomes of eukaryotes
    - different protein and RNA content
  • the genes for these rRNAs are often used for classification
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

bacterial genomes

A
  • the prokaryotic genome has less DNA than the eukaryotic genome
  • the typical prokaryotic genome is a ring of DNA (a circular chromosome) that is not surrounded by a membrane and that is located in a nucleoid region
  • some species of bacteria also have smaller rings of DNA called plasmids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

smaller rings of DNA in bacterial genomes- plasmids

A
  • plasmids can replicate independently of the chromosome
  • often have genes useful for the survival of the bacteria (e.g. for resistance to antibiotics, or for the ability to metabolize a particular nutrient like lactose)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

prokaryotes divide by

A

binary fission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

eukaryotes dived by

A

mitosis/meiosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

bacterial classification - historically

A
  • microscopic observations (e.g. shape, response to stains)
  • biochemical characteristics (& growth conditions)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

bacterial classification - more recent

A
  • serological characterization (using antibodies/immune response)
  • compare DNA sequences (% similarity of rRNA genes)
    - for clinical analysis, we can identify bacteria using PCR (a method to amplify DNA)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

bacterial morphologies - coccus

A

circle/sphere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

bacterial morphologies - bacillus

A

rod shaped

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

bacterial morphologies - vibrio

A

curved rod shape/comma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

bacterial morphologies - spirillum

A

squiggly/ spiral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

bacterial morphologies - staphylo

A

cluster

15
Q

bacterial morphologies - diplo

A

pairs of spheres

16
Q

bacterial morphologies - strepto

A

line

17
Q

peptidoglycan

A

is used for support in bacterial cell walls

18
Q

gram stain - red/pink

A

gram-negative

19
Q

gram stain - purple

A

gram-positive

20
Q

gram-negative bacteria have

A

less peptidoglycan and an outer membrane that can be toxic, and they are more likely to be antibiotic-resistant

21
Q

gram-positive stain

A
  • thick wall
    - peptidoglycan
  • e.g. bacillus anthracis
22
Q

gram-negative stain

A
  • thin wall between 2 membranes
  • e.g. e.coli
23
Q

gram-negative - periplasm

A
  • the region between the membranes
    • contains enzymes which can degrade toxins & antibiotics
24
Q

gram-negative - lipopolysaccharides (LPS)

A
  • a unique lipid/carbohydrate found on the outer layer of the outer membrane
  • LPS is an endotoxin (may cause a severe immune reaction
25
Q

toxins

A

are substances (such as proteins) produced by some microorganisms that can cause pathologic effects associated with infectious diseases
- non-infectious (they cannot be transmitted from person to person)
- non-replicating
- can cause acute toxic disease, as well as long-term effects
- classified as either endotoxins or exotoxins

25
Q
A
26
Q
A
27
Q
A
28
Q
A
29
Q
A
30
Q
A