bacteria Flashcards Preview

Ap Biology > bacteria > Flashcards

Flashcards in bacteria Deck (50)
Loading flashcards...
1
Q

first living things

A

anaerobic, heterotrophic, and bacteria

2
Q

traits all organisms got from universal common ancestor

A

DNA( universal genetic material- same nucleotides and double helix)
DNA replication to reproduce (semiconservative with same enzymes like helicase and polymerase)

3
Q

Domains

A
domain bacteria (most primitive, branched off first), domain archaea (live in old ways like extreme environments)(archaeobacteria)
domain eukarya
4
Q

bacterial ancestral traits

A

no histones,

single main chromosome

5
Q

bacteria cellular structures

A
Nucleoid 
Plasmid 
 Ribosomes
 Pili
 Capsule
Flagella
6
Q

nucleoid

A

main chromosome

7
Q

plasmid

A

small circular DNA trading cards, extra copies of important genes

8
Q

pili

A

projections of cell membrane, how plasmids are passed

9
Q

capsule

A

gelatinous coating

10
Q

flagella

A

with no microtubules/basal body

11
Q

what type is bacterial replication

A

asexual, rapid, only differences are produced with mutations

12
Q

bacterial replication process

A

Origin duplicated
DNA helicase unwinds DNA
DNA polymerase complex called replisome
2 replication forks move opposite directions
Topoisomerase cuts DNA to avoid over-coiling

13
Q

prokaryotic fission process

A

Origins attach
Cell elongates-through adding phospholipids to elongate space between origins
Cytoplasmic division
No random assortment

14
Q

how to get genetic variation in bacteria

A

lateral genetic exchange- giving genes to friends and neighbors, not genetically related, not linear

15
Q

advantages to lateral gene transfer

A

rapid passing of new phenotypes

16
Q

conjugation

A

bacteria to bacteria via tube, direct contact

17
Q

transduction

A

virus introduces new DNA, injects bacterial DNA by accident

18
Q

transformation

A

uptake of DNA through cell membrane (plasmids)

gaining new phenotypes by the environment through the cell membrane

19
Q

famous transformation experiment by Griffith

A

infects mouse with rough and smooth pneumonia. Lives with rough, but dies with smooth because it protects from immune system. Killed smooth strand put in with rough strands, and mouse dies because the smooth transfers plasmids to rough bacteria

20
Q

bacterial conjugation process

A

. Donor cell (F+) gives a plasmid to recipient cell
F+ fertility plasmid directs sex pilus formation (forms tube)
Conjugation tube joins cytoplasm
Relaxase nicks donor plasmid (cuts covalent bond in backbone and then unwraps helix)
One strand of plasmid nucleotides moves into recipient cell
Both strands replicated back into double helix

21
Q

bacterial mutation rates

A

very high due to reproduction rates

22
Q

identifying/classifying bacteria

A

Characteristics that are considered

a) Shape
b) Gram staining ( + or -)
c) Metabolism
d) Gene sequencing

23
Q

gene sequencing

A

causes re-structuring of classification

shows genetic divergence from all other life shortly after emergence of first cell

24
Q

shape cocci

A

round

25
Q

shape bacilli

A

rod

26
Q

shape spirilli

A

spiral

27
Q

cell arrangements diplo

A

pairs

28
Q

cell arrangements strepto

A

chains

29
Q

cell arrangements staphylo

A

bunches

30
Q

gram staining

A

used when bacteria is hard to treat, can be positive or negative

31
Q

gram staining positive

A

picks up stain so turns violet, want positive because most antibiotics can get to cell, lots of peptidoglycan in cell wall

32
Q

down side of gram staining positive

A

form endospores

33
Q

gram staining negative

A

stains red, less peptidoglycan

outer membrane- resistant to drugs, membranes make it hard to get antibiotics to the cell

34
Q

Peptidoglycan =

A

sugars cross-linked by peptides

35
Q

Chemoheterotrophs –

A

E from bonds, organic C

parasites, saprobes, decomposers

36
Q

Chemoautotrophs –

A

E from bonds, C from CO2

thermophilic bacteria, some of most primitive. Energy from iron or sulfur compounds (volcanos)

37
Q

Photoautotrophs –

A

E from sun, C from CO2

cyanobacteria, stromatolites

38
Q

what does gene sequencing show?

A

Shows bacteria diverged from all other lineages shortly after first cells appeared, made it why we needed domains

39
Q

example of an analogous structure for eukaryotic and prokaryotic

A

flagella

40
Q

bacteria flagella

A

ATP run protein motor,

has a hook & filament

41
Q

Archean flagella

A

same design as bacteria, ATP run protein motor with a hook & filament, but different proteins

42
Q

eukaryotic flagella

A

is covered in a membrane and has microtubules with basal body

43
Q

Signal transduction –

A

extra cellular signaling molecule binds to receptor and initiates response

44
Q

taxis

A

innate behavioral response to move toward or away from directional stimulus

45
Q

4 types of taxis

A

magnetotactic (magnetic fields)
phototactic (light)
thermotactic (heat)
geotactic (gravity)

46
Q

kinesis

A

non-directional change in activity in response to a stimulus (bad feeling, need to move, don’t know where just move)

47
Q

quorum sensing

A

intercellular communication Bacteria use signaling molecules (specific to species) to sense bacterial cell density. inducible operon

48
Q

in quorum sensing what happens with sufficient signal molecule concentration

A

triggers communal response
gene expression activated,
proteins produced & excreted

49
Q

QS enables bacteria to

A

to co-ordinate their behaviour. As environmental conditions often change rapidly, bacteria need to respond quickly in order to survive. ex; bacteria in body to escape immune system,

50
Q

virulence bacteria

A

Virulence factors are molecules expressed and secreted by pathogens that enable them to achieve:
colonization of a niche in the host
Immunoevasion- evasion of the host’s immune response
Immunosuppression- inhibition of the host’s immune response
Entry into and exit out of cells