Structureof Prokaryotic Eukary

Nucleus vs nucleoid DNA : circular vs linear, presence of histonesMembranous organellesCell wall-peptidoglycanCell division: binary vs mitosisRibosomes: 70S vs 80SCytoskeleton

CocciDiplococciStreptococciTetradsSarcinaeStaphylococci

CoccobacilliDiplobacilliStreptobacilli

Vibrio-curved rodsSpirilla-helical & rigidSpirochetes-helical & flexibleOther shapesPleomorphic

Glycolipids or glycoproteinsSurrounds cell Capsule or slime layerCapsule more organized & attached to wallAdvantages of capsule

Surrounds cellLoosely organized & not attachedTangled mass of fibers-dextranAttachment to surfaces -S. mutansShields bacteria from immune defense &

antibiotics

Animal cells have oneMade of carbohydratesNo do not have a cell wallSurround plasma membraneStabilizes PM

MovementSpins like propellerClockwise or counter clockwise

Chemotaxis- movement toward or away

Monotrichous: one at endAmphitrichous: both endsLophotrichous: tuft at end or endsPeritrichous: around the cell

Composition-protein subunits: flagellin (H protein) E. coli H7Chains twisted together with hollow coreHelical shapedFilament, hook, basal bodyHookBasal body:

Basal body

Classified by flagella protein

SpirochetesTreponema pallidum-syphilisBorrelia burgdorferi-Lyme disease

Bundle of fibrials within a sheathCorkscrew motion

Flagella & cilia

9+2 arrangement of microtubules

Cilia in Paramecium & respiratory cells

Made of pilin: string of subunits

Function: attachment

Few to hundredsFimbrae

Pili-longer & fewer

Not in eukaryotes

Function

Basis of Gram stain

PeptidoglycanRepeating subunits of disaccharides

N-acetyl glucosamine (NAG) N-acetyl muramic acid (NAM)Linked alternately in rows

Attached by polypeptidesTetrapeptide side chains link NAM subunitsCross bridge of amino acids link tetrapeptides

Forms lattice

Confers shape & prevents lysisCell growth

Autolysins break cross linkages in peptidoglycan

Transpeptidases seal breaksPenicillin inactivates these enzymes

Existing cellsTreat with lysozyme-tears, saliva etc.Destroys linkages between carbohydrates

Thick layers: 40-80% of dry wt, up to 30 layers

Contains teichoic acidAlcohol and phosphateNegative charge

Cell growth-prevents lysisAntigenic properties

Few layers of peptidoglycan- 10%Outer membrane: bilayer

Periplasm

Strong negative charge

Barrier to some antibiotics

Outer membrane-endotoxinO polysaccharidesLipid-lipid A

Penicillin:

Lysozyme:

Differential stain dev by Hans Gram 1880sClassifies bacteria into 2 groupsBased upon cell wall compositionGram variable stain unevenly

Gram non reactive do not stain or stain poorly

Gram positives

ETOH disrupts outer layerCV-I complex is washed out of thin

peptidoglycan layerCounterstain

Streptococci

Mycobacteria

MycoplasmaPM unique with sterols protect from lysis

Lack a cell wall so pleomorphicClassified with gram positivesSmallest genome of any bacteria

Droplet spread-use regular maskWhy can’t you use penicillin?

Simpler than prokaryotes Algae & plantsFungiYeastsProtozoa

Animals

Thin, fluid structure inside cell wall-viscousProteins

Phospholipids-2 layers

Selective permeabilityPassive transport:Active transport: Enzymes break down nutrientsInfoldings

Phospholipids and proteinsCarbohydrates and sterols-cholesterolMore rigid than prokaryotic PMEndocytosis

Exocytosis

80% water, thick, solutesInflux of water, increase in osmotic pressure

on membraneRigid cell wall prevents lysis

Contains DNARibosomesInclusion bodies

Cytosol-fluid portionCytoskelton

Microfilaments: Microtubules:

Intermediate filaments:Cytoplasmic streaming

Single, ds DNA chromosomeAttached to PM at some pointNucleoid area, not a nucleusPlasmids

Largest structure in cell

Nucleoli

DNA associated with proteins -histones

2 subunits of protein and rRNA70s ribosomesPolyribosomes-chainsProtein synthesisAntibiotics inhibit protein synthesis

Polysaccharide granules

Sulfur granules

Reserve deposits-volutin (phosphates)

Unique to bacteria: Clostridium & BacillusSporulation-formation of spores

Triggered by damage to coatEnzymes break down endosporeWater enters & metabolism beginsNot a reproductive structure

Unique to eukaryotesMembranous structures

Endoplasmic reticulumSmooth & rough

Golgi complexLysosomesMitochondriaCloroplasts

Flattened membranous sacsRough ER-ribosomes attached

Smooth ER- no ribosomes

Free ribosomes- proteins don’t need processing

Stacks of membranous sacsReceive transport vesicles from ERModify molecules to form glycoproteins,

glycolipids lipoproteins Transported in secretory vesicles to PM or to

outside cell

Formed from GolgiContain digestive enzymes: proteases &

nucleasesBreak down old parts of cellBreaks down pathogens

Double membrane

Generation of ATP

Thylakoids-flattened membranous sacs

Contain DNA 70s ribosomesStroma thick fluid in center- Calvin cycleGeneration of ATP & sugars