Bacteria + Archaea + Eukarya Flashcards
(83 cards)
1
Q
bacteria evolved
A
3.5-4 bill yrs ago
2
Q
bacteria cause
A
- bubonic plague
- typhoid
- tuberculosis
- cholera
- gonorrhea
- lepsory
- botulism
- whooping cough
3
Q
do bacteria have introns?
A
no
4
Q
bacteria are
A
- opportunistic
- only cause illness when defense are weakened
5
Q
linking diseases to bacteria began in the late 1800s. who was first to make this connection?
A
Robert Koch (used anthrax and tuberculosis)
6
Q
Koch’s postulates (4)
A
- FIND SAME PATHOGEN IN EACH: researcher must find the same pathogen in each diseased individual
- ISOLATE PATHOGEN: isolate pathogen from diseased and grow in pure culture
- INDUCE DISEASE: induce disease into experimental animals by transferring the pathogen from the culture
- RE-ISOLATE: after (if) disease develops, re-isolate the same pathogen from experimental animals
7
Q
super-bugs are aggravated/created by
A
excessive antibiotic use
8
Q
beneficial prokaryotes
A
- prod vitamins
- decompose org material
- recycle nutrients (C, S, N)
9
Q
how many bacterial cells have been found in oceans?
A
10^29
10
Q
why are prokaryotes difficult to classify?
A
- limited fossil record
- structural simplicity
- DNA swapping (HGT)
11
Q
phylogeny of prokaryotes is now determined by
A
sequencing regions of the SSU-rRNA
12
Q
how small are bacteria?
A
200nm to 2microm
13
Q
bacteria shape
A
- cocci
- bacilli
- spirilla and spirochetes
14
Q
what do bacterial cell walls do?
A
- maintain shape
- protects from hypotonic envs
- contain peptidoglycan
15
Q
bacterial movement
A
flagella
- convergent evolution with euk flagella
16
Q
reproduction
A
- no sex
- binary fission
- speedy
17
Q
bacterial genomes
A
- 1/1000th as much DNA as in euk genomes
- very little non-coding DNA (85% coding)
- genomic degradation
- circular chromosomes
- 20 000 genes
- approx. 3 billion chromosomes in genome
- 17 000 bp’s
18
Q
how much of our DNA is non-coding?
A
98.5%
19
Q
circular chromosomes
A
- 15% noncoding
- in nucleoid region
- not bound to histones
20
Q
operon
A
cluster of genes under the control of a single promoter
21
Q
plasmid
A
- small circular pieces of DNA
- 2000 to 10 000 bps
- can be horiz transferred
22
Q
biotech: to amplify a gene of interest
A
- using recombinant DNA tech
1. cut gene out with restriction enzyme
2. put it into a plasmid
3. seal with DNA ligase
4. mix w/ bacteria
23
Q
3 ways prokaryotes exchange DNA
A
- transformation
- transduction
- conjugation
24
Q
transformation
A
- incorporate foreign DNA from surrounding env
- Frederickson
25
transduction
movement of genes btwn bacteria by bacteriophages
26
conjugation
- involves cell-to-cell contact
| - sex pili allow DNA transfer
27
cDNA
DNA with introns removed = RNA + reverse transcriptase (used to make human insulin)
28
like bacteria, archaea have...
- no membrane-bound organelles
- circular chromosomes
- similar ribosomes
29
like eukarya, archaea have...
- no peptidoglycan
- introns (in some)
- have histones
30
archaea live in...
- low E envs
| - marginal habitats
31
3 types of archaea
- methanogens (prod methane)
- halophiles (salty)
- thermophiles (hot)
32
phototrophs
obtain e from light
33
chemotrophs
obtain e from chemicals
34
autotrophs
need only inorganic CO2 to make org molecs
35
heterotrophs
need to consume at least 1 org molec
36
nitrogen fixation
- breaking the N triple bond and make it into NH3/NH4+
37
obligate aerobes
req O2 for cellular respiration
38
facilitative anaerobes
will use O2 if present, but can use fermentation
39
obligate anaerobes
poisoned by O2 and use fermentation
40
bacterial success
metabolic diversity & fast repro
41
euk success
diversity of shapes and sized, and fine control of gene expression
42
mixotrophs
photo + hetertrophic
43
dynamic cytoskeleton (3)
- faster/bigger
- change shape
- movement and phagocytosis
44
endomembrane system moves molecs faster or slower than diffusion?
faster
45
linear chromosomes (2)
- replicate multiple strands simultaneously
| - large non-coding regions function in gene regulation
46
genetic diversity in bacteria is due to?
horizontal gene transfer
47
sex promotes diversity in euks in two ways
1. gametes are genetically unique
| 2. fertilization is random
48
sperms differ from each other due to (2)
1. recombination/crossing over
| 2. independent assortment
49
genetic diversity in euks
- dynamic cytoskeleton and membrane system
- complex gene regulation
- genetic diversity via sex
50
oldest euk fossils
1.8 bill yrs
51
problems with protista
- defined by exclusion
- poly/paraphyletic
- members not closely related
52
how many species of protists are there?
70 000 +
53
how do protists move?
cilia or flagella
54
protist diseases (4)
malaria, African sleeping sickness, amoebic dysentery, giardia
55
how did the endomembrane system evolve?
infolding the of the plasma membrane
56
endosymbiosis
proposes that mitochondrian and chloroplasts were independent prokaryotes
57
evidence that organelles were once free living
- appearance
- genomes
- enzymes
- ribosomes
- binary fission
58
secondary endosymbiosis
euk eating a euk that has eaten a prok and all retaining membranes
59
why discontinuous presence of Photosynth?
euks acquired Photosynth multiple times by repeated episodes of endosymbiosis
60
7 major superkingdoms of euks
1. amoebazoa
2. archaeaplastids
3. opisthokonts
4. stramenopila
5. alveolate
6. excavates
7. rhizarians
61
ameobozoa contains
- amoebas
- slime molds
- cellular slime molds
62
Archaeplastida contains
- chlorophyta
| - rhodophyta
63
stramenopila contains
- diatoms
| - brown algae
64
alveolate contains
- dinoflagellates
- apicomplexans
- ciliates
65
excavates contains
- euglenids
- trypanosomes
- diplomonads
66
amoebozoa characteristics
- many are unicellular
- found in soil and aquatic envs
- use phagocytosis
- reproduce via mitosis or nuclear fusion
67
amoebas
- lobe shaped pseudopodia
- unicellular heterotrophs
- amoebic dysentry
68
slime molds
- fruiting bodies that prod spores
| - plasmodial and cellular
69
cellular slime moulds
- good conditions, one-celled amoeba
- bad conditions, slug like thing
- individual/multicellularity
70
Archaeplastida characteristics
- cell wall w cellulose
| - chloroplasts are surrounded by two membranes
71
chlorophyta
- green algae
- can be unicellular, colonial, or multicellular
- 10,000 species
72
rhodophyta
- no flagellated sperms
- live in deep w
- red
73
stramenopila characteristics
- have hair like projections on their flagella
| - some heterotrophic, some photoauto's
74
diatoms
- common phytoplankton
- chloroplasts have 3 membranes (2ndary endosymbiosis)
- glass-like walls of hydrated cilica
75
brown algae
- kelp
- complex anatomy similar to plants
- no vascular tissue
- convergent evolution
- Photosynth w "leaves", using bladders to float them close to the sun
76
alveolata characteristics
- very diverse
| - presence of cortical alveoli sacs under their membranes
77
dinoflagellates
- phytoplankton
- foundation of marine food chains
- spin b/c of 2 flagella in perpendicular grooves
- red tide
- zooxanthellae form mutualistic symbioses w/ corals and anemones
78
apicomplexans
- parasites (eg. plasmodium, cicle cell anemia)
| - intricate life cycles
79
ciliates
- diverse
| - use cilia to move and feed
80
excavates characteristics
- basal flagella
| - cytoskeletons
81
euglenids
- anterior pocket w 1/2 flagella
- often mixotrophic
- photosynth
82
trypanosomes
- African sleeping sickness
| - freq changes in surface proteins prevent host developing immunity
83
diplomonads
- lack mitochondria (lost 2ndarily)
