Mcb 3020C Cell Structure Test 2

Front 1

Frequency of sterols in prokaryotic cells?
Exception to prokaryotic trend?
Function of sterols in eukaryotic cells?

Back 1

-Usually absent in prokaryotes

-Mycoplasma has no cell wall so it uses sterols

-Stabilizes membrane; rigid and planar

Front 2

What kind of environment do mycoplasma live in?

Back 2

osmotically protected

Front 3

Molecules similar to sterols, called __________, are present in the membranes of many Bacteria and may play a role similar to that of sterols in eukaryotic cells. Example?

Back 3

-hopanoids

-diplotene

Front 4

Are hopanoids present in all bacterial membranes? When are they likely to be present?

Back 4

-no

-likely to be present in bacteria that live in unfavorable environments

Front 5

Components of Archaeal Cell membrane?

Analogs of Eubacteria?

Back 5

-L-Glycerol, ether linkage, isoprene unit chains, phosphate

-D-Glycerol, ester linkage, fatty acid chains, phosphate

Front 6

_________ and ________ are the major classes lipids present in Archaea. Examples of each?

Back 6

-Glycerol diethers; Phytanyl (20C)

-diglycerol tetraethers; Biphytanyl (40C)

Front 7

A tetra ether is actually?

Back 7

di-biphytanyl di-glycerol tetra ether

Front 8

Alternative component of Archaeal membrane that contains rings?

Back 8

Crenarchaeol: 5 & 6 C Rings

Front 9

-Produces a lipid monolayer; Typically extremely resistant to heat denaturation; Found in hyperthermophiles

-Produces the lipid bilayer

Back 9

-diglycereol tetraether

-glycerol diether

Front 10

Some membranes are a _______ of monolayers & bilayers

Back 10

mixture

Front 11

Simple Diffusion and Facilitated Diffusion are differentiated by ability to be

Back 11

saturated

Front 12

Driving force in each of the following:
-Simple Transport
-Group Translocation
-ABC Transporter

Back 12

-Proton Motive Force
-Phosphoenolpyruvate
-ATP

Front 13

Example of a symporter in E.Coli?

Back 13

Lac Permease - moves lactose and protons

Front 14

The best studied model of group translocation involves the transport of the sugars _______, _______ and _______, which are ________ during transport by the __________ system

Back 14

-glucose, mannose and fructose

-phosphorylated

-phosphotransferase

Front 15

-Nonspecific components of the phosphotransferase system?

-Specific Components?

Back 15

-Enz-1 and HPr

-Enz-2a, Enz-2b, Enz-2c

Front 16

Proteins transported are synthesized as presecretory proteins called _______ that have a signal peptide at ________ terminus recognized by Sec

Back 16

-preproteins

-amino

Front 17

___________ bind to signal peptides & delay protein folding to keep it in conformation

Back 17

-chaperon proteins

Front 18

_________ removes signal peptide and protein folds into shape

Back 18

-Signal peptidase

Front 19

Most important function of cell wall?

Back 19

Protection from osmotic pressure

Front 20

Peptidoglycan components:

Back 20

-Sugars: N-Acetylglucosamine and N-Acetylmuramic Acid

-Amino Acids: L-alanine, D-glutamic acid, either lysine or diaminopimelic acid (DAP), and D-alanine

Front 21

The small group of amino acids (L-alanaine, D-alanine, D-glutamic acid and either lysine or DAP) are connected to

Back 21

N-acetylmuramic acid

Front 22

Bonds of peptidoglycan?

Can be cleaved by?

Back 22

-Heteropolymer GMGMGM; Beta glycosidic linkage is between the 1 carbon of N-acetylglucosamine and the 4 carbon of N-acetylmuramic acid

Front 23

Similarities of DAP and Lysine?

Differences?

Back 23

-Both have two amino groups - diaminoacids

-DAP has extra carboxyl group - diamino dicarboxylic acid

Front 24

The sugar _________ and the amino acid ___________ are never found in the cell walls of Archaea or Eukarya

Back 24

-N-acetylmuramic acid

-diaminopimelic acid

Front 25

________ are polyalcohols, polyglycerol phosphates, or polyribotol phosphates and are only found in gram positive

Back 25

teichoic acids

Front 26

Examples of bacteria with no cell wall?

Back 26

Mycoplasma and Thermoplasma

Front 27

-The backbone of pseudopeptidoglycan in Archaea is composed of alternating repeats of _______ and _________.

-Type of bonds?

Back 27

-N-acetylglucosamine and N-acetyltalosaminuronic acid

-1,3 Beta linkages (not 1,4)
-pseudopeptidoglycan = pseudomurein

Front 28

Order of layers from outer to inner in LPS?

Back 28

Outermost: O-specific polysaccharides

Core polysaccharides

Innermost: Lipid A

Front 29

How is the LPS linked to the cell wall?

Back 29

linked to Glucosamine (of peptidoglycan) through Amine groups

Front 30

Capsules and Slime layers are secreted slimy or sticky material that consists of either _________ or ________.

Back 30

polysaccharide (most) or protein

Front 31

Pili are similar to fimbriae but are generally ______ in length and can act as ___________ for viruses.

Back 31

-longer
-receptors

Front 32

H2S often oxidized to sulfur to produce _________, which are stored in ________

Back 32

-sulfur globules
-periplasm

Front 33

Notable genera of spore forming bacteria? Cell shape of each, aerobic or anaerobic?

Back 33

-Bacillus are gram + aerobic robs

-Clostridium are gram + anaerobic rods

Front 34

One chemical substance that is characteristic of the endospore core but not present in vegetative cells is _________

Back 34

dipicolinic acid

Front 35

Functions of dipicolinic acid?

Back 35

-Ionic form complexes with calcium and dehydrates cell
-Intercalates between DNA bases & stabilizes DNA to prevent denaturation

Front 36

SASPS: Small Acid-Soluble Proteins

Back 36

-Function as C & E source for outgrowth of a new vegetative cell from endospore during germination

Front 37

How do SASPS protect DNA from damage by UV radiation & drying

Back 37

Change molecular structure of DNA form B to A form.
A is more compact
A form is more resistant to formation of pyrimidine dimers by UV, a mechanism of mutation

Front 38

Endospore components?

Back 38

Exosporium (protein)
Spore coat (protein)
Cortex (peptidoglycan)
Core (spore protoplast)

Front 39

Exosporium made up of?

Back 39

protein

Front 40

Spore coat made up of ?

Back 40

protein

Front 41

Cortex made up of ?

Back 41

peptidoglycan

Front 42

Core made up of?

Back 42

spore protoplast