Exam 1 chapter 2 Flashcards
prokaryotic comes from the greek words
pre-nucleus
eukarytic comes from the greek word
true nucleus
karyon is greek for
nut/kernal
eukaryotes have
histones
oganelles
polysacharide cell walls
mitotic spindle
paired chromosomes in nuclear membrane
prokaryotes have
one ciruclar chromosome no membrane
no histones
no organelles
bacteria: peptidoglyan cell walls
archaea-psuedomurein cell walls
binary fission
moephology means
shape
most bacteria are
monomorphic (some pleomorphic)
3 Major bacterial cell morphologies
coccus (spherical)
bacillus(rod shaped)
spiral
diplo, clusters, and chains are abbreviations for what shapes
pairs, clusters, chains
Size range for prokaryotes:
0.2 μm to >600
μm in diameter
Size range for eukaryotic cells
5 to >100 μm in
diameter
Small cells have more ________
relative to cell volume than large cells
surface area
small cells Tend to grow ____ than larger cells
faster
cell wall of prokaryotes do what
Prevents osmotic lysis
Bacteria divided into two broad groups based on cell
wall can be shown different by
stained with the Gram stain
gram positive
thick peptidoglycan
teichoic acids
gram negative
thin peptidoglycan
outer membrane
periplasmic shape
Disaccharide polymer is made of
N-acetylglucosamine (NAG)
N-acetylmuramic acid (NAM
peptidogylcan made of
disacharide polymer
amino acid bridges
and lysine or diamonopimelic acid
gram positive cell walls contain _____ peptidoglycan
90%
gram positive cell walls have _____ acids
teichoic
gram positive cell walls may regulate movement of
cations
polysacharides provide _________ in gram positive cell walls
antigenic variation
Gram Negative Cell Walls contains about _____ peptidoglycan
10%
in Gram Negative Cell Walls most of the cell wall is composed of
outer membrane
Gram-Negative Outer Membrane provides protection from
phagocytes, complement, and
antibiotics
key features of Gram-Negative Outer Membrane
O polysaccharide antigen, e.g., E. coli O157:H7
Lipid A is an endotoxin
Porins (proteins) form channels through membrane
Gram Stain Mechanism for positive
crystal violet-iodine (CV-I) crystals form in cell
alcohol dehydrates peptidoglycan
CV-I crystals do not leave
Alcohol dehydrates
peptidoglycan
Gram Stain Mechanism for negative
Crystal violet-iodine (CV-I) crystals form in cell
Gram-positive
Alcohol dissolves outer membrane and leaves holes in
peptidoglycan
CV-I washes out
An additional protective layer commonly
found in free-living bacteria and archaea
S layer
where is the s layer located
outermost layer
the s layer is a
Crystalline layer of thick subunits consisting
of protein or glycoprotein
the s layer may contribute to
cell shape
and help protect the cell
from osmotic stress
what are the Atypical Cell Walls
Acid-fast cell walls, Mycoplasmas, archaea
Mycoplasmas lack
cell walls, and sterols in plasmsa membrane
archaea are wall-less or walls are
pseudomurein
pseudomurein
lack NAM and D-amino acids
Acid-fast cell walls
Like gram-positive cell walls
Waxy lipid (mycolic acid) bound to peptidoglycan
Also includes unusual sugars (arabinogalactans)
Mycobacterium and Nocardia
Glycocalyx characteristics
cell wall, sticky, involved in biofilm formation,
capsules in glycocalyx prevent
phagocytosis and dehydration
in glycocalyx there are 2 types
Capsule: neatly organized
Slime layer: unorganized and loose
flagella
Allow for motility, Via rotation
Extends outside the cell wall
Made of chains of flagellin (protein)
Attached to a protein hook
Anchored to the wall and membrane by the
basal body
Fimbriae
Protein structures
Allow attachment
Flagella proteins are ____ antigens
H
pili usually longer then a
Usually longer than fimbriae
types of pili
Conjugation Pilus, Type IV Pilus
type IV Pilus
Gliding motility/Twitching motility
Attachment
conjuction pilus
Facilitate transfer of DNA from one cell to
another
functions of the plasms membrane
protein enachor, permability, defines existence
location of proton motive force
plasms membrane
structure of the plasms membrane phospholipid bilayer
made up of proteins
what proteins make up plasms membrane
peripheral proteins and integral proteins
plasms membrane movement
proteins move to function, phospholipids rotate and move laterally
A ______ consists of
glycerol with ester links to
two fatty acids and a
phosphoryl head group
phospholipid
the two layers of
phospholipids in the bilayer
are called
leaflets.
_____ have the most extreme variations in
phospholipid side-chain structures
Archaea
archaea’s Lipids lack fatty acids; have ___
isoprenes
archaea Exist as
lipid monolayers, bilayers, or a mixture
what causes leakage of cell contents in plasms membrane
Damage to the membrane by alcohols, quaternary
ammonium (detergents), and polymyxin antibiotics
in plasmsa membrane Photosynthetic pigments on foldings are called
chromatophores or thylakoids
plasms membrane enzymes help with ____
ATP
plasmsm membrane has Secretion of
virulence factors and communication
signals
Simple diffusion
movement of a solute from an
area of high concentration to an area of low
concentration
Facilitated diffusion
solute combines with a
transporter protein in the membrane
osmosis
the movement of water across a
selectively permeable membrane from an area of
high water to an area of lower water concentration
osmotic pressure
the pressure needed to stop the
movement of water across the membrane
osmosis occurs through ______ in aquaporins
lipid bilayer
aquaporins are
water channels
Active Transport Systems used to transport nutrients against
concentration
gradients
active transport system requires a ______ and _____
transporter protein and energy in some
form
three major types of active transport systems in prokaryotes
Simple transport
Group translocation
ABC system
three possible transport events
uniport, antiport, symport
uniport explain
one goes through
antiport explain
one comes in and one can come out at same time
symport explain
2 can enter same side same time
The substance inside the plasma membrane
cytoplasm
nuceloid describe
haploid
no histones
closed circular
bacterial chromosome
haploid
single set of chromosomes
the nucleoid forms
about ___ loops or
domains.
50
in nuceloid Within each
domain, the DNA is
supercoiled by DNA-
binding proteins.
The Escherichia coli
nucleoid appears as
clear regions that
exclude the ____
and contain the___
ribosome; DNA
strands.
function of prokaryotic ribosomes
protein synthesis
the strcutre of a prokaryotic ribosome is
70S-50S+30S subunits
cell inclusions are
non-living, non-membrane-bound structures found within the cytoplasm of cells
(cell inclusions) Polysaccharide granules important
energy reserves
importance of the cell inclusion- Polyphosphates
inorganic phosphate
important of the cell inclusions sulfur globules
elemental sulfur
important of the cell inclusion Carboxysomes
Ribulose 1,5-diphosphate
carboxylase
for CO2 fixation
importance of the cell inclusion Magnetosomes
magnetic storage inclusions
what is the cell inlcusion gas vessicles
protein-covered cylinders
endospores are the ______ stage of bacterial cell cycle
dormant
endospores are Resistant to
desiccation, heat, chemicals, and
radiation
endospores Can be dispersed
by wind, water, feces
sporulation does what
endospore formation
structure of endospore
has a little bit of water, lots of dipicolinic acid and calcium ions, it also has a small acid-soluable spore proteins
the endospore spore structure
core, cortex, outer membrane, endospore coat, exosporium
Histones are in
eukaryotes
Histone-like proteins in
prokaryotes
cytoskeleton structure in n eukaryotes composed of:
microfilaments, intermediate
filaments, microtubules
cytoskeleton structures in prokaryotes composed of
actin and tubulin homologs
ribosomes are responsible for
protein synthesis
eukaryotes are __S
80
prokaryotes are ___S
70
in eukaryotes ribosomes are located
Membrane-bound: attached to ER
Free: in cytoplasm
in prokaryotes ribosomes ar elocated
in chloroplasts and mitochondria
Think of these implications
in eukaryotes the nucleus contains
chromosomes
what organelles are found in eukaryotes
ER
GOLGI compelx
Lysosome
Vacuole
Mitochondion
Chloroplast
Peroxisome
Centrosome
ER is a
transport network
golgi compelx does what
membrane formation and secretion
lysosome is the
digestive enzyme
vacuole
brings food into cells and provides support
mitochondrion is responsible for
cellular resperiation
chloroplast is responsible for
photosynthesis
peroxisome does what
oxidates of fatty acids; destroys H2O2
centrosomes consist of
protein fibers and centrioles
