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NEU Microbiology Spring 2011 Lec 3
These flashcards cover all review material presented for the end of lecture 3 (chapter 4)
36
Microbiology
Undergraduate 1
01/20/2011

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Cards

Term
Is cell morphology a good predictor of other properties of the cell?
Definition

Morphology typically doesn't affect other various properties but it could affect things like nutrient/ion uptake and movement abilities

Term
What physical property of cells increases as cells become smaller?
Definition

Their surface-to-volume ratio increases as they get smaller

Term
Contrast the linkage between glycerol and the hydrophobic portion of lipids in bacteria and archaea
Definition

Glycerol is facing outwards on either side of the membrane while the hydrophobic portions are facing inwards

Term
List 2 reasons why a cell can't depend on diffusion as a means of acquiring nutrients
Definition

Some compounds are just flat out too big to diffuse through the membrane and various nutrients that have a certain charge associated with them can't be passed through the membrane either

Term
Why is peptidoglycan such a strong molecule?
Definition
It's a very rigid molecule and its structure is interlinking
Term
What does the enzyme lysozyme do?
Definition

It degrades the bond between the N-acetylmuramic with the fourth carbon of N-acetylglucosamine which essentially destroys the cell wall

Term
What components constitute the LPS later of gram - bacteria?
Definition

LPS consists of the core polysaccharide and O-polysaccharide

Term
Why does alcohol readily decolorize gram - but not gram + bacteria?
Definition
Term
What is the ABC (ATP binding cassette) transport system?
Definition

The ABCTS is a membrane transport system consisting of three proteins, one of which hydrolyzes ATP, which transports specific nutrients into the cell

Term
What is the basal body?
Definition

The basal body is the "motor" portion of the bacterial flagellumm, embedded in the cytoplasmic membrane and wall

Term
What is a capsule?
Definition

A capsule is a polysaccharide or protein outermost layer, usually rather slimy, present on some bacteria

Term
What is chemotaxis?
Definition

Chemotaxis is the directed movement of an organism toward (positive chemotaxis) or away from (negative chemotaxis) a chemical gradient

Term
What is dipicolinic acid?
Definition

Dipicolinic acid is a substance unique to endospores that confers heat resistance on these structures

Term
What is an endospore?
Definition

An endospore is a highly heat resistant, thick-walled, differentiated structure produced by certain gram+ bacteria

Term
What is a flagellum?
Definition

A flagellum is a long, thin cellular appendage capable of rotation and is responsible for swimming motility in prokaryotic cells

Term
What are gas vesicles?
Definition

Gas vesicles are gas-filled cytoplasmic structures bounded by protein which confer buoyancy on cells

Term
What are gram- bacteria?
Definition

Gram- bacteria are prokaryotic cells whose cell wall contains small amounts of peptidoglycan, and an outer membrane containing lipopolysaccharides, lipoproteins and other complex macromolecules

Term
What are Gram+ bacteria?
Definition

Gram+ bacteria are prokaryotic cells whose cell walls consist chiefly of peptidoglycan and lacks the outer membrane of gram- bacteria

Term
What is a gram stain?
Definition

A gram stain is a differential stain technique that stains cells either purple (Gram+) or pink (Gram-)

Term
What is group translocation?
Definition

Group translocation is an energy-dependent transport system in which the substance transported is chemically modified during the transport process

Term
What is a lipopolysaccharide (LPS)?
Definition

A lipopolysaccharide is a combination of lipid with polsaccharide and protein that forms the major portion of the outer membrane in gram- bacteria

Term
What is a magnetosome?
Definition

A magnetosome is a particle of magnetite (Fe3O4) organized into a nonunit membrane-enclosed structure in the cytoplasm of magnetotatic bacteria

Term
What is morphology?
Definition

Morphology is the shape of a cell

Term
What is the outer membrane?
Definition

The outer membrane is a phospholipid and polysaccharide-containing unit membrane that lies external to the peptidoglycan layer in cells of gram- bacteria

Term
What is peptidoglycan?
Definition

Peptidoglycan is a polysaccharide composed of alternating repeats of N-acetylglucosamine and N-acetylmuramic acid arranged in adjacent layers and cross-linked by short peptides

Term
What is the periplasm?
Definition

The periplasm is a gel-like region between the outer surface of the cytoplasmic membrane and the inner surface of the lipopolysaccharide layer of gram- bacteria

Term
What is peritrichous flagellation?
Definition

Peritrichous flagellation  consists of flagella located in many places around the surface of the cell

Term
What is phototaxis?
Definition

Phototaxis is the movement of an organism toward light

Term
What are pili?
Definition

Pili are thin, filamentous structures that extend from the surface of a cell and, depending on type, facilitate cell attachment, genetic enchange or twitching motility (depending on specific function)

Term
What are polar flagellations?
Definition

Polar flagellations are organisms which have flagella which eminate from one of both poles of the cell

Term
What is poly-(beta)-hydroxybutyrate (PHB)?
Definition

PHB is a common storage material of prokaryotic cells consisting of a polymer of (beta)-hydroxybutyrate or another (beta)-alkanoid acid or mixtures of (beta)-alkanoic cells

Term
What is the protoplast?
Definition

The protoplast is an osmotically protected cell whose cell wall has been removed

Term
What is the S layer?
Definition

The S layer is an outermost cell surface layer composed of protein or glycoprotein present on some bacteria and archaea

Term
What is a simple transport system?
Definition

A simple transport system is a transporter that consists of only a membrane-spanning protein and typically driven by energy from the proton motive force

Term
What is sterol?
Definition

Sterol is a hydrophobic heterocyclic ringed molecule that strengthens the cytoplasmic membrane of eukaryotic cells and a few prokaryotes

Term
What is teichoic acid?
Definition

Teichoic acid is a phosphorylated polyalcohol found in the cell wall of some gram+ bacteria

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