Micro Exam 1 Test Questions – Flashcards

Unlock all answers in this set

Unlock answers
question

Transmembrane protein

Integral protein

Peripheral protein

answer

t: protein that spans the entire biological membrane; type of intergral protein

i: protein that is permanently attached to the biological membrane

p: temporarily adhere to the biological membrane; attach to integral

question
Nicholson-Singer fluid mosaic membrane model
answer

membrane/proteins are capable of lateral motion

some proteins embedded in membrane

in prokaryotic or eukaryotic

still considered most viable model of membrane since 1972

question
2 structures for membrane stabilization
answer

1. Sterol- planar molecule, eukaryotic, cholesterol

2. hopanoid- 5 rings structure, prokaryotic, diploptene hopanoid

question
Membrane functions (6)
answer

1. Semipermeable barrier

2. Regulation (metabolite uptake, waste release)

3. Redox reactions (electron transport systems)

4. Coordination of binary fission and sporulation (septum formation)

5. Synthetic reactions

6. Chemotaxis/sensing apparati

question
3 types of synthetic reactions
answer

- lipids

- peptidoglycan

- secretory proteins

question
How do molecules pass through a biological membrane?
answer

Phagocytosis

Endocytosis

Exocytosis

question
Passive diffusion vs. facilitated transport
answer

p: water/co2 can simply diffuse high to low through membrane

f: need transport or carrier protein when available

question
Other terms for facilitated diffusion
answer

Transporters

Permeases

Facilitators

Carriers

question
Sources of energy in a cell
answer

ATP- adenosine triphosphate

PMF- proton motive force (electrochemical gradient)

question
2 types of transporters
answer

MFS- major facilitator superfamily

IDS- ion dependent transport system

** depend on concentration gradient**

question
Cotransport systems (3)
answer

Utilize energy of PMF

1. Symport- same way down channel, prokaryotic sugars/ eukaryotes

2. Antiport- one in, one expelled

3. Uniport- one one material down channel

question
Efflux system
answer

part of antiport

expulsion of antibiotic or waste

question
ABC transport system
answer

ATP binding cassette

3 regions:

1. Solute binding protein (SBP)- attaches to appropriate protein and brings to mouth of channel (g+ can diffuse away, g- close because of periplasm)

2. Membrane spanning domain (MSD)- 2 barrel channel through protein, 12 alpha helices lining

3. Nucleotide binding domain (NBD)- binding of ATP

question
Group translocation system
answer

Prokaryotes only

chemically alters substrate

12 alpha helices in transmembrane protein

phosphorylation energy from PEP

question
Do prokaryotes or eukaryotes have more proteins?
answer

Prokaryotic - 800

Eukaryotic- 225

question
Bactoprenol
answer
transports NAM and NAG across the cell membrane in the synthesis of peptidoglycan
question
Secretory systems (4)
answer

Translocase (expulsion)

Sec system

Type III (injectisome)

Signal sequence

question
Sec system
answer

- secA translocase- secretion and insertion of proteins in the cell membrane

- leader sequence of 15-20 amino acids

question
Type III secretion system
answer

- AKA: injectisome

- in gram negative bacteria

- produce a toxin that inserts into eukaryotic cell

question
Characteristic structures when the cell membrane invaginates
answer

- still continuous with cell membrane

- see by electron microscopy

- structures: tubes, vesicles, bundled tubes, stacks, lamellae

question
Another name for glycocalyx
answer
EPS- extracellular polymeric substance
question
Types of glycocalyces
answer

1. capsule- distinct gelatinous layer for protection/attachment

2. slime layer- diffuse and irregular layer for protection/attachment

question
Visualization of glycocalyx
answer

external to cell wall

do not stain well

- negative/background stain (stain everything were not interested in)

- india ink

question
3 bacteria causing pneumonia
answer

Klebsiella pneumoniae

Streptococcus pneumoniae

Mycoplasma pneumoniae

question
Glycocalyx colonies (2)
answer

1. smooth- AKA mucoid, mucous/stringy

2. rough- little extracellular matrix material

question
Chemical composition of glycocalyx
answer

primarily sugar polymers (polysaccharides)

few amino acids (polypeptides)

question
What makes up polysaccharides?
answer

glucans and dextrans

(glucose)

question
What genus gives a proteinacious glycocalyx?
answer
Bacillus spp.
question
Glycocalyx functions (6)
answer

1. Adhesions/adherence

2. Protection against dessiccation

3. Protect against bacteriophage infecton and noxious chemicals

4. Carbohydrate reserve (?)

5. Protection against elimination by phagocytosis (virulence mechanism)

6. Classification and type specific markers for Streptococcus pneumoniae 

question

Biofilm

(definition and 3 examples)

answer

polysaccharide encased mass of bacteria coating a surface

- can only cause disease if encapsulated

ex) Streptococcus mutans - dental plaque

Streptococcus pneumoniae - low bar pneumonia (elderly)

Haemophilis influenzae- infections in children (ear)

question
Classification by type specific markers
answer
K or Vi antigens
question
Dental caries
answer

dental plaque

Streptococcus mutans

most common infectious disease

due to excess sucrose

attaches to teeth, anaerobic environment, sugar ferments, acid prodcued, tooth erosion

question
Types of pili/fimbriae
answer

1. Conjugal, fertility, sexual- has to do with genes (uncommon)

2. Somatic/body- designated by type and function

question
CFA & PAK
answer

CFA: colonization factor antigen in E. coli

PAK: causes thrush

question
Functions of pili
answer

1. gene transfer (conjugation)

2. Anti-phagocytic

3. Adherence

question
Adherence mechanisms among prokaryotes (2)
answer

Afimbrial: due to glycoclayx, adhesins embedded

Fimbrial: due to fimbriae/pili, adhesins at end of pilus with O markers

question
E. coli fimbrial systems (5)
answer

1. ETEC- enterotoxinogenic ecoli- binds to enterocytes in intestinal epithelium

2. EIEC- enteroinvasive ecoli

3. EAEC- enteroaggregative ecoli

4. EPEC- enteropathogenic ecoli

5. EHEC- enterohemorrhagic ecoli (O157)

question
Fimbrial system bacteria (3)
answer

Klebsiella pneumoiae

Pseudomonas aeruginosa (cystic fibrosis)

Candida albicans (eukaryotes, fungus, PAK)

question

Tropism

(definition and 2 examples)

answer

act on cell with appropriate receptor

Streptococcus pyogenes - receptors in back of the throat

Bordetella pertusis- whooping cough, receptors in respiratory tract

question
Flagella shapes (5)
answer

1. Monotrichous: polar, single flagella on one side

2. Amphitrichous- 2 to 4 flagella on both sides

3. Lophotrichous- many flagella on one side

4. Peritrichous- flagella all around, evenly distributed

5. Atritrichous- no flagella, still motile

question
Sinusoidal shape of flagella
answer

same wavelength and amplitude

rigid

helical

question
Pilin
answer
protein subunits of pili that are unique in every pilus
question
3 components of flagella
answer

Basal body/granule

Hook

Filament

question

Basal body/granule

(definition & g+/g-)

answer

- tube with several sets of rings attached

in every bacterial cell w/ flagella

- anchors flagellum to cell wall/membrane

g-: 2 sets of rings, top & by stator, perimplasmic space

g+: one set of rings around stator

question
Stator
answer

part of basal body/granule

where motion is generated from PMF

rapid rotation

embedded in cell membrane

question
Hook
answer

-part of flagella that swings out due to centrifugal force

-amino acids/proteins

-connects filament to cell surface

question
Circumferential slip
answer

push or pull bacteria from aqueous environment

- due to rotation from basal body

- drill bit

question
Filament
answer

rigid

rotates

extends into exterior environment

majority of flagella (stringy)

question
3 ways to identify flagella
answer

1. leifsons flagellar stain: salt along flagella visible with light microscopy

2. wet mounts- see organism as it moves through aqueous environment

3. motility detection medium

question
Spirochetal Ultrastructure
answer

type of flagella in spirochetes

spirillum morphology

AKA: endoflagella & axial fibrils

question
Inside spirochetal ultrastructure
answer

1. peptidoglycan: patches, flexible

2. axial filaments: folded inside cell

3. protoplasmic cylinder: cell membrane, peptidoglycan, outer sheath

question
Where is flagella in spirochetal ultrastructure? How does it move?
answer

- inside (endoflagella)

- pairs that overlap

- moves by internal rotation- entire body rotates

question
Spirochetosis baceria
answer

Treponema spp. (treponematosis)

Leptospira spp.

Boriella spp.

question
Treponema bacteria (4)
answer

Treponema pallidum- syphillis

Treponema microdentia

Treponema denticole

Treponema vincentii- ANUG: acute necrotizing ulcerative gingivitis 

question
Leptospira spp. is from what and causes what disease?
answer

from contaminated waters

causes weils disease

question
Lymes disease bacteria
answer
Borrelia burgdorferi
question
Nucleoid characteristics (7)
answer

1. Chromatin material

2. Electron opaque region by EM

3. Covalently closed double stranded circular DNA

4. Haploid

5. Multiple identical copies

6. Associated with cell membrane

7. Can be stained and seen by light microscopy

question
mbp in nucleoid compared to eukaryotic cell
answer

mbp: million base pairs

nucleoid = 4.5

eukaryotic = 40 to 50

question
Supercoiled DNA
answer

- compactness

- replication requires breaking one strand

- need enzymes: topoisomerase II/DNA gyrase to wind, topoisomeras IV to unwind

- unique to prokaryotes

- ex) E. coli is 2-3 nm big, but 1 mm of DNA fits

question
Plasmid functions (3)
answer

1. extrachromosomal DNA (outside chromosome)

2. Non- essential genes

3. Replication

question
Episomes
answer

can jump into chromosomes

considered to be extrachromosomal DNA

question
Non-essential genes
answer

- gives advantages in environment

- pathogenicity islands- clustered together to form virulence mechanism

ex) having an extracellular matrix

question
2 types of replication in plasmids
answer

Relaxed: have necessary information to replicate itself

Stringent: replicated with bacterial chromosome present

question
Types of plasmids (3)
answer

1. Engineered genes for genetic engineering workbench

2. Virulence plasmids for pathogenicity islands

3. R (resistance) factors- genes that inactivate antibiotics

question
R plasmids
answer

- R factors (whole plasmid) can be transferred to other bacteria

- Self transmissable (itself) vs. mobilizable (help)

-  R factors are not limited to antimicrobials

- All linked, 6-12 antibiotic resistance

question
RTF
answer

resistance transfer factor

- genes necessary for replication

- conjugation

- resistance to antibiotics

- resistance to elements: antimony, arsenic, mercury, lead

question
Ribosomal function
answer

protein synthesis

joining of amino acids

question
Ribosome ultrastructure
answer

70S: prokaryotic, 30S + 50S

80S: eukaryotic

- differences are targets of antibiotics

- higher number = faster to settle, higher density

- highly conserved rRNA and protein

- significance in medicine

question
Endospore details (4)
answer

1. produced by specific genera: bacillus spp. & clostridium spp.

2. Resistance structure: no reproductive value, resistant to extremes

3. Produced under threatening environmental conditions and complex developmental program

4. Long state of dormancy

question
Bacillus & Clostridium spp. examples (4)
answer

Bacillus anthracis

Clostridium botulinum- food exotoxin

Clostridium tetani- tetanus

Clostridium perfringens - gas gangrene

question
Sporulation and germination
answer

s: formation of endospore, low C/N amount

g: exit dormant stage and create vegetative cell by cortex cracking

question
Identification of endospores (5)
answer

1. Position

2. Size

3. Shape: central/metacentric, subterminal, terminal

4. Laminated appearence

5. Unique chemical compostion

question
Endospore stain and common location
answer

stain: schaefer-fulton

location: soil

question
Gonnorhea bacteria
answer
Neisseria gonorrhoeae
Get an explanation on any task
Get unstuck with the help of our AI assistant in seconds
New