Chapter 27: Bacteria and Archaea Flashcards
1
Q
Bacteria Overview
A
- oldest most successful group
- unicellular
- lack nucleus, organelles
- found in all locations, diverse enviroments
2
Q
Bacteria Shape
A
- 3 common shapes
- Cocci (sphere)
- Bacilli (rod)
- Spirilla (spiral)
3
Q
Cell Wall structures
A
- have a cell wall
- categorized by composition
- Peptidoglycan
4
Q
Gram Stains
A
- Gram Positive: large amount of peptidoglycan that traps violet dye in the cytoplasm
- Gram Negative: has less peptidoglycan, and is located in a layer between the plasma membrane and an outer membrane
5
Q
Cell Surface Structure
A
- Capsule or slime layer
- covers cells wall
- used for
- adherence
- defensive shield
6
Q
Endospore
A
- Protective coat
- Surrounds DNA
- dormant for centuries
7
Q
Fimbriae
A
Hairlike; allows for adherence
8
Q
Flagella
A
- Used for movement
- Demonstrate taxis
- movement toward or away from stimulus
9
Q
Prokaryotic Genome
A
- circular chromosomes, located in nucleoid region
- some also have small rings of DNA called plasmids
10
Q
Prokaryotic Reproduction
A
reproduce by binary fission
11
Q
Genetic Variation
A
- ultimate source is mutations
- diversity is due to genetic recombination
- 3 mechanisms:
- Transformation - obtain DNA from environment
- Transduction - virus transfers genes b/w bacteria
- Conjugation - genes transferred b/w bacteria called horizontal gene transfer
12
Q
Nutritional Modes
A
Genetic Diversity allows for modes of nutrition
13
Q
Metabolism
A
- is the making and breaking of substances
- Various metabolism
- Obligate Aerobes - require and use oxygen
- Facultative anaerobes - can use or not use oxygen
- Obligate anaerobes - poisoned by oxygen
14
Q
Phylogeny
A
is tentative; based on molecular systematics
15
Q
Domain Bacteria
A
- 5 groups
- Spirochetes
- Chlamydias
- Cyanobacteria (photoautotrophs)
- 2 Largest Groups:
- Proteobacteria
- Gram- Positive Bacteria
