Exam (elaborations)
bacteriology exam 1 questions with complete solutions
- Course
- Institution
bacteriology exam 1 questions with complete solutions
[Show more]
Content preview
bacteriology exam 1 questions withcomplete solutions
how is the genome different in pro- v eu-karyotes - correct answer ✔✔prokaryotes: 1 chromo, may have
extrachromosomal DNA =plasmids
eukaryotes: mult chromosomes, extrachromasomal DNA = mitochondria
what is the structure of organelles in pro- v eu-karyotes - correct answer ✔✔pro: DO NOT have
membrane bound organelles in the cytoplasm
eu: do have membrane bound organelles --> nucleus, ER, golgi app
what are the basic external structures of a bacteria - correct answer ✔✔surface layers: S layer + capsule
appendages: flagella, pili, fimbriae
what are the boundaries of a bacteria - correct answer ✔✔-outer membrane
-cell wall
-cytoplasmic membrane
what is the fx of the cell wall - correct answer ✔✔maintains integretity of the cell (eg keeping osmotic
pressure in check)
*the only one that doesnt have this is mjicroplasma
what is the fx of the outer membrane - correct answer ✔✔-facilitates nutrient acquisition
-virulence
-protection
**some have, not all
,what is the fx of the cytoplasmic membrane - correct answer ✔✔(fragile, needs protection)
-controls nutrients coming in and out of the sytoplasm
-needs protection! this is why the cell wall is impt
what are the internal components of a bacteria - correct answer ✔✔-cytoplasm
-ribosomes
-inclusion
-nucleoid/chromosome
-cytoskeleton
-endospore
-plasmid
what is the main difference between gram pos and gram neg bacteria - correct answer ✔✔the
components of the cell wall (one can be decolorized and restained (neg), the other cant (pos)
what is the comp of the cell wall for a gram pos bacteria - correct answer ✔✔-they have a cell
membrane
-they have a large/thick peptidoglycan layer
-the surface proteins are on top of the peptidoglycan layer
-gives rigitiy and cell shape
-protects from osmotic challenge and some toxic compounds
what is the comp of the cell wall of a gram neg bacteria - correct answer ✔✔-cell membrane
-thin peptidoglycan layer
-lipoprotein layer
-outermembrane = lipopolysaccharide (LPS) with surface proteins in it)
-can have porins --> allow molecules into the cell (hydrophilic) and eject molecules out
,*uses the other membrane (LPS) for protection
what are the 2 main shapes of bacteria? - correct answer ✔✔rods and cocci (spherical)
-generally 1-10um in length and 0.2-1 um in width
-but they can come in many shapes and sizes
how do we commonly group bacteria? - correct answer ✔✔using gram status and shape
-gram pos rods
-gram pos cocci
-gram neg rods
*dont really see gram neg cocci in vet med but are mucosal flora
what are different examples of bacterial attachement - correct answer ✔✔-fimbriae
-biofilm
-capsule
what is fimbriae - correct answer ✔✔-protein structures on the outside of the cell
-fine, harilike that faciliate adhesion through "grappling hook-like" mechanism
-usually distributed all over the cell surface
-can aid in ID
*amino acid comp of the proteins may be changed in oder to evade immune syst (good target Ag for
immune cells)
what is biofilm - correct answer ✔✔-aggregate of bacteria and extracellular components
-forming complex comminites, often a single spp but not always
, -helps bacteria survive in adverse conditions (decreases immune response, anti microbial drugs are
unable to penetrate through matrix well)
*occurs on implants and invasive devices, in tussues
what is a capsule - correct answer ✔✔in addition to a cell wall, they can have a layer external to cell wall
with mult functions. usually comp of polysaccharides and tightly bound to the cell wall)
-avoid phagocytosis
-resistance to toxic substances
-adherence
what is the S layer - correct answer ✔✔the "slime layer"
-less robust than the capsule
-monolayer of protein used for protection and attachment
-loose structure and loosely adhered to cell (can wash away, but still helpful for protection and
attachment)
what are types of tools do bacteria use to move - correct answer ✔✔-flagella
what is flagella - correct answer ✔✔-long round filaments embedded into cell wall (change direction
with change in rotation
-facilitates spread in response to chemotactic signals (with in environment)
-can be used to ID bact
what are bacterial mechanisms of DNA exchange - correct answer ✔✔-conjugation
-tranformation
-transduction
what is pilus - correct answer ✔✔-mechanism for bacterial cell to cell sharing of chromosomal or
plasmid DNA called conjugation
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller BravelRadon. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $22.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
82871 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now