1 - Cell Biology –Intro to Cell Biology
-
Upload
anthony-james -
Category
Documents
-
view
280 -
download
3
Transcript of 1 - Cell Biology –Intro to Cell Biology
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
1/34
Introduction to the Study of
Cells
Chapter 1
Pages 1-24
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
2/34
Discovery of Cells RobertHooke:corkcomposedofsmallchambersReportedin1665
Madepossiblebydevelopmentofmicroscope
Termedporouschambers"cells"Actuallyobservedcellwalls
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
3/34
Anton van Leeuwenhoek: first descriptions
of cellsGroundlensesashobby
Observedprotistsinpondwatertermed"animacules"
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
4/34
Importance of cells realized in 1830s with
publication of 2 papersMatthiasSchleiden:plantscomposedofcells
TheodorSchwann:first2tenetsofcelltheory Allorganismsarecomposedofoneormorecells
Thecellisthestructuralunitoflife
Schleiden Schwann
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
5/34
Rudolf Virchow: third tenet of cell theory in1855
Cellscanariseonlybydivisionofapreexistingcell
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
6/34
Basic Properties of Cells
1. Highlycomplexandorganized
Differentlevelsoforganization
atoms molecules macromolecules complexes organelles cells tissues
Mostbasicprocessesandstructuresremarkablysimilarinallorganisms
Informationfromoneorganismgenerallyapplicabletootherorganisms
Modelorganismsforintensiveinvestigation
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
7/34
Bacterium
Escherichia coli
Yeast
Saccharomycescerevisiae
Model Organisms
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
8/34
Nematode
Caenorhabditis elegans
Flowering PlantArabidopsis
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
9/34
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
10/34
Basic Properties of Cells2. Possessgeneticprogramandmeanstouseit
Genesblueprintsforcellularconstruction&activities
3. Capableofreproduction
4. Acquire
and
utilize
energy
Requireconstantinputofenergy
Conversionofelectromagneticradiationtochemical
energystored
in
carbohydrates
Conversionofstoredchemicalenergyintousableformforcellularactivities(usuallyATP)
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
11/34
5. Carryoutavarietyofchemicalreactions
Sumtotalofchemicalreactionsincellmetabolism
6. Engageinnumerousmechanicalactivities
Structuresassembledanddisassembled
Materialstransportedfromplacetoplace
Manycellsmove7. Respondtostimuli
Receiveandreacttosignalsfromothercellsandtheenvironment
8. Capableofselfregulation
Obviouswhenregulatorymechanismsbreakdown
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
12/34
Two Classes of Cells Basedoninternalcomplexity
Prokaryoticcellsofarchaebacteriaandeubacteria
Eukaryoticcellsofallotherorganisms
Namefrompresence/absenceofnucleus Karyon=kernelornucleus
Pro
=
before Eu=wellortruly
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
13/34
Common Characteristics of Prokaryoticand Eukaryotic Cells
1. Similarconstruction
of
plasma
membrane
2. GeneticinformationencodedinDNA
3. Similarmechanisms
for
synthesizing
proteins
transcriptionandtranslation
Madebyribosomessimilarbutnotidenticalin
prokaryoticand
eukaryotic
cell
4. Sharemetabolicpathways
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
14/34
Common Characteristics of Prokaryoticand Eukaryotic Cells
5. Similarmechanism
for
ATP
production
6. Similarmechanismofphotosynthesis
(cyanobacteria
and
green
plants)7. Similarmechanismforsynthesizingand
insertingmembraneproteins
8. Similarproteasomesstructuresfordigestion
ofproteinsincytosol
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
15/34
Unicellular eukaryotic organisms range fromrelatively simple (yeast)
to perhaps the most complex ofall cells (protozoa and algae)
Eukaryotic cells more complex
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
16/34
Activities of multicellular organisms dividedamong different types of specialized cells
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
17/34
Features of Eukaryotic Cells not Found inProkaryotes
OrganizationofDNA
Longlinearstrandsassociatedwithproteins
Capableofcondensingintomitoticchromosomes
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
18/34
DNAsegregatedinnucleus
Complexmembranedelimitedorganellesin
cytoplasm
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
19/34
Specializedorganellesforaerobicrespirationand
photosynthesismitochondria
and
chloroplasts
ContainownDNAandproteinsynthesizingmachinery
Divide
to
increase
number
Believedtohavecomefromprokaryoticcellsengulfedbyeukaryoticancestor
mitochondria chloroplast
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
20/34
Endoplasmicreticulum(ER)systemofinterconnectedflattened
sacs
and
tubes
Originof mostcellmembranecomponentsandmaterialsexportedfromcell
SmoothversusRoughER dependentonpresenceofribosomes
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
21/34
Golgiapparatus
Stackofflattenedsacs ReceivesmoleculesfromERanddirectsthemappropriate
destination
Oftenmodifiesmoleculesinprocess
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
22/34
Lysosomes(protozoaandanimalcells)
Oftenirregularlyshapedwithheterogeneousinterior Sitesofintracellulardigestion
Peroxisomes Membraneboundedwithgranularinteriorandoftenwith
crystallinecore
Siteofchemicalreactionscoupledtosynthesisand
degradationof
hydrogen
peroxide
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
23/34
Vacuoles(serveaslysosomesinplantcells)
Differenttypesofsmallvesiclesfortransportbetweenorganelles
Processesofendocytosisforingestingfluidandparticulatematerial,andexocytosisforreleaseof
materialfromcell
2003 Encyclopedia Br itannica, Inc.
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
24/34
actin filaments microtubules intermediate filaments
Complexcytoskeletalsystem
Givescellmechanicalstrength
ControlscellshapeOrganizescytoplasmDrivesandguidesmovements
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
25/34
Major Differences in Features ofProkaryotic & Eukaryotic Cells
Eukaryotic Structureofciliaand
flagellacomplex
Cellulosiccellwallwhenpresent
Multiplechromosomes
Prokaryotic Bacterialflagellaless
complex
Peptidoglycancellwallusuallypresent
Singlecircularchromosome
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
26/34
Major Differences in Features ofProkaryotic & Eukaryotic Cells
Eukaryotic Mitosisutilizing
microtubulecontaining
spindle
Sexualreproductioninvolvingmeiosisand
fertilization
Prokaryotic DuplicatedDNAseparated
bygrowthof cell
membrane
CapableofexchangingpiecesofDNAbutnotrue
sexualreproduction
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
27/34
Unique Characteristics of Archaea Cellwallsdonotcontainpeptidoglycan;contain
auniquemolecularstructureunlikeeubacteria
oreukaryotes Slayer
DNAisassociatedwithhistonelikeproteins
ProteinsynthesizingenzymesandRNApolymerasesmorecloselyresemblethoseof
eukaryotes
Membranelipidsareunique,resembling
neithertheeubacteria oreukaryotes
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
28/34
Unique Characteristics of Archaea
Oftenreferredtoasextremophilesbecauseof
theenvironmenttheyliveinandthematerials
theyutilize
for
energy
(sugar,
ammonia,
sulfur,
hydrogen,metals)
Methanogens oxygenispoisonoustothem
Halophiles liveinhighsaltenvironments
Thermoacidophiles orThermophiles Cannot
surviveat
low
temperatures
(55C)
Endoliths liveinsiderocks,canutilizemineralsor
metalsasanenergysource.
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
29/34
3 Domain System
ProposedbyCarlWoesein1990
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
30/34
Cells are small
Diameter of a sphere in microns (m)
Vo
lumeofa
spherein
nanolite
rs(nL)
100 m diameter = 0.52 nL
300 m diameter = 14.14 nL
3X versus 27X
1 m = 10-6 meters1 nm = 10-9 meters
1 = 10-10 meters
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
31/34
Cells are small Synthesisoflimitednumberofmessagesfromset
amountDNAinagiventime
Thelargerthevolume,thelongerthetimerequiredtomakenumberofmRNAsneededbycell
Decreaseinsurfacearea/volumeratiowithincreasein
size Surfacenotsufficienttotakeupsubstancesrequiredfor
metabolicactivitiesbeyondcertainsize
Diffusionresponsibleformovementofmanysubstancesintoandoutofcell Timerequiredfordiffusionproportionaltosquareofdistance
traversed
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
32/34
Viruses
Smallerandsimplerthanbacteria
Wide
variety
of
shapes
andsizes
ObligateIntracellularparasites
Outsidecell Virion=geneticmaterial+proteincoat(capsid)
Ds
or
Ss
RNA/DNA NOreproduction,metabolism,anyactivitiesassociatedwithlife
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
33/34
Human Immunodeficiency
Virus (HIV)
Bacteriophage
-
8/11/2019 1 - Cell Biology Intro to Cell Biology
34/34
Viruses Mosthavenarrowhostrange;changecanbe
devastating 1918flupandemic(25%ofthe
worlds
population
infected;
3%
died
50
100
millionpeople.
TwotypesofinfectionLytic
StableIntegration(severaloutcomes)
Viroids RNAonly