Prokaryotes: Bacteria & Archaea Flashcards
(61 cards)
1
Q
Prokaryotes thrive almost everywhere:
- ——: can live in very high salinities
- ——: can survive 3 million rads of radiation (3,000 x human fatal dose)
- ——: can live at temperatures as high as 80° C (176° F)
- ——: can grow at pH 0.03 (acidic enough to dissolve metal)
A
- Halobacterium Species
- Deinococcus Radiodurans
- Thermus Aquaticus
- Picrophilus Oshimae:
2
Q
Prokaryotes are most —, and likely the —, orgnaisms on earth
A
- Abundant
2. First
3
Q
Prokaryotes are divided into what 2 domains?
A
- Bacteria
2. Archaea
4
Q
We actually have more — cells than our — cells
A
- Bacterial
2. Own
5
Q
Because bacteria are so much smaller, only comprise about —% of our body weight
A
0.3%
6
Q
Common features among all cells:
- ——
- —
- ————
- —
A
- Plasma Membrane
- Cytoplasm
- Double-stranded DNA Genome
- Ribosomes
7
Q
Cell Wall:
- — have peptidoglycan
- — lack peptidoglycan
A
- Bacteria
2. Archaea
8
Q
DNA replication:
- Both have single origin of —
- Archaeal DNA replication is more similar to that of —
A
- Replication
2. Eukaryotes
9
Q
Gene Expression:
*Archaeal — and — are more similar to those of eukaryotes
A
- Transcription
2. Translation
10
Q
Autotrophs – carbon from inorganic CO2
- —: energy from Sun
- —: energy from oxidizing inorganic substances (e.g., H2S, NH3 or Fe2+)
A
- Photoautotrophs
2. Chemolithoautotrophs
11
Q
Heterotrophs – from organic molecules:
*—: light as energy source but obtain organic carbon made by other organisms
*—: both carbon atoms and energy from organic molecules
Humans are another example
A
- Photohetrotrophs
2. Chemoheterotroph
12
Q
Prokaryotic metabolism varies with respect to O2:
- ——: require O2 for cellular respiration
- ——: poisoned by O2 and use anaerobic respiration/fermentation
*——: use O2 if present, but also carry out anaerobic respiration/fermentation if not
A
- Obligate Aerobes
- Obligate Anaerobes
- Facultative Anaerobes
13
Q
Most prokaryotes are:
- —, although some species form colonies
- 0.5–5 µm, much — than eukaryotic cells (10–100 µm
A
- Unicellular
2. Smaller
14
Q
Prokaryotic cells have a variety of shapes; 3 most common are:
- —
- —
*—
A
- Spheres (cocci)
- Rods (bacilli)
- Spirals
15
Q
An important feature of nearly all prokaryotic cells is their cell wall:
- Maintains ——
- — the cell
- Prevents — in a hypotonic environment
A
- Cell Shape
- Protects
- Bursting
16
Q
Eukaryotes (plants and fungi): made of — or —
A
- Cellulose
2. Chitin
17
Q
Prokaryotes:
- Bacteria: contain —, a network of sugar polymers cross-linked by polypeptides
- Archaea: contain — & — but lack peptidoglycan
A
- Peptidoglycan
2. Polysaccharides & Proteins
18
Q
Used to classify bacteria by cell wall composition
- ———: have less peptidoglycan and an outer membrane that can have toxic lipopolysaccharides
- ———: have simpler cell walls with a large amount of peptidoglycan
A
- Gram-negative bacteria
2. Gram-positive bacteria
19
Q
Gram-negative bacteria:
- —— of — in cell walls are toxic, causing fever or shock
- Tend to be more —— because outer membrane impedes drug entry
A
- Lipid portions of lipolysaccharides (LPS)
2. Antibiotic resistant
20
Q
Gram-positive bacteria:
- Some are — and — to one or more antibiotics
- Many antibiotics (e.g., penicillin) target — and damage bacterial ——
A
- Virulent & Resistant
2. Cell walls
21
Q
Capsule: —— or —— that covers some prokaryotes
*Allows adherence to the —, or other individuals, and can shield pathogenic bacteria from the host immune system
A
- Sticky polysaccharide
- Protein layer
- Substrate
22
Q
—: extensions of some prokaryotes that help them stick to their substrate or other individuals in a colony
A
Fimbriae
23
Q
—: longer than fimbriae and allow prokaryotes to exchange DNA
A
Pili
24
Q
Most motile bacteria propel themselves by —
- Scattered about the surface or concentrated at one or both ends
- — of bacteria, archaea, and eukaryotes perform similar functions, but are composed of different proteins and likely evolved independently
A
- Flagella
2. Flagella
25
~Half of all prokaryotes exhibit —: the ability to move toward or away from a stimulus
*E.g., — is the movement toward or away from a chemical stimulus
1. Taxis
| 2. Chemotaxis
26
Internal structure is simpler than in eukaryotes
| *Prokaryotic cells usually lack ——
Complex compartmentalization (organelles)
27
Some prokaryotes do have specialized membranes that perform ——
* There are usually — of the plasma membrane
1. Metabolic functions
| 2. Infoldings
28
Physical arrangement of DNA is also simpler:
* Prokaryotes lack a —; chromosome is located in the — region with no surrounding membrane
* Prokaryotic genome has — DNA than the eukaryotic genome
* Most of the genome consists of a —chromosome
* Typical prokaryotes also have smaller rings of independently replicating DNA called —
1. Nucleus
2. Nucleoid
3. Less
4. Circular
5. Plasmids
29
Key features of prokaryotic reproduction:
*—
*Reproduce by ——
*Have — generation times
~Can divide every — hours under optimal conditions
~As a result, populations can reach trillions of individuals
1. Small
2. Binary fission
3. Short
4. 1-3
30
Short generation time allows prokaryotes to evolve —
Quickly
31
Prokaryotes are not “—“ but are highly —
1. Primitive
| 2. Evolved
32
Prokaryotes have considerable ——
Genetic variation
33
3 factors contribute to this genetic diversity is prokaryotes:
* ——
* —
* ——
1. Rapid Reproduction
2. Mutation
3. Genetic Recombination
34
Mutation rates during binary fission are —, but because of rapid reproduction, mutations can accumulate — in a population
1. Low
| 2. Rapidly
35
— diversity from mutations allows for — evolution
1. High
| 2. Rapid
36
Genetic recombination is the combining of — from — sources
1. DNA
| 2. Two
37
Prokaryotic DNA from different individuals can be brought together by:
* —
* —
* —
1. Transformation
2. Transduction
3. Conjugation
38
—: taking up and incorporation of foreign DNA from the surrounding environment
*E.g., nonpathogenic Streptococcus pneumoniae can be transformed to pneumonia-causing strain if exposed to DNA from pathogenic strain
Transformation
39
—: movement of prokaryotic genes between bacteria by bacteriophages
*Usually results from accidents that occur during the phage replicative cycle
Transduction
40
—: process where genetic material is transferred between prokaryotic cells
Conjugation
41
In bacteria, the DNA transfer is always ——
One way
42
A donor cell attaches to a recipient by a pilus, pulls it closer, and transfers DNA through “——”
Mating Bridge
43
A piece of DNA called the —— is required for the production of pili
F Factor (F for fertility)
44
F Factor can exist either as a:
* —
* Segment of — within the bacterial —
1. Plasmid
2. DNA
3. Chromosome
45
Cells containing the F factor as a plasmid (F+) function as — donors during —
1. DNA
| 2. Conjugation
46
Cells without the F factor (F-) function as —— during conjugation
DNA Recipients
47
An F+ cell converts an F- cell to F+ if a copy of the entire F plasmid is —
Transferred
48
A cell with the F factor built into its chromosomes also functions as a donor during conjugation
*Called an ——
Her Cell (for High Frequency of Recombination)
49
F- cells also function as DNA recipients during — with ——
1. Conjugation
| 2. Hfr Cells
50
The recipient becomes a — F- bacterium, with genomic DNA from two different cells
*—— become an F+ or Hfr cell! No F factor is retained.
1. Recombinant
| 2. Does NOT
51
——: carry genes for antibiotic resistance
R Plasmids
52
Antibiotics kill antibiotic-sensitive bacteria, but not — with specific —— that counter the antibiotic
1. Bacteria
| 2. R Plasmids
53
Through ——, the fraction of bacteria with genes for resistance — in a population exposed to antibiotics
*Antibiotic-resistant strains of bacteria are becoming — common
1. Natural Selection
2. Increases
3, More
54
Some prokaryotes are ——, but many others have — interactions with humans
1. Human Pathogens
| 2. Positive
55
Human intestines are home to about —— species of bacteria
500-1,000
56
Many of the species of bacteria in humans are — and break down food that is undigested by our intestines
Mutualists
57
— cause about half of all human diseases
| * E.g. Lyme disease is caused by a — and carried by ticks
1. Bacteria
| 2. bacterium
58
Pathogenic prokaryotes typically cause disease by releasing:
* —: secreted and cause disease even if the prokaryotes that produce them are not present
* —: released only when bacteria die and their cell walls break dow
1. Exotoxins
| 2. Endotoxins
59
Prokaryotes are the principal agents in —, the use of organisms to remove pollutants from the environment
Bioremediation
60
Bacteria can be engineered to produce —,—,— & ——
1. Vitamins
2. Antibiotics
3. Hormones
4. Natural Plastics
61
Bacteria are also being engineered to produce — from waste biomass
Ethanol
