chapter 10 cell growth & division section 10–1 cell growth
TRANSCRIPT
Chapter 10Chapter 10Cell Growth & DivisionCell Growth & Division
Section 10–1Section 10–1Cell GrowthCell Growth
ObjectivesObjectives
What problems does growth cause What problems does growth cause for cells?for cells?
Limits To Cell GrowthLimits To Cell Growth
Key ConceptKey Concept::The The LargerLarger A Cell Becomes, The A Cell Becomes, The More DemandsMore Demands The Cell Places The Cell Places On Its DNA And The More On Its DNA And The More Trouble The Cell Has Moving Trouble The Cell Has Moving Enough Nutrients And Waste Enough Nutrients And Waste Across The Cell MembraneAcross The Cell Membrane
DNA OverloadDNA Overload
Extra Copies Of DNA Are Not MadeExtra Copies Of DNA Are Not Made Like A Small Town – Infrastructure Like A Small Town – Infrastructure
Needs To Grow As The Town GrowsNeeds To Grow As The Town Grows
DNA OverloadDNA Overload
Exchanging MaterialsExchanging Materials
Cell Membrane Cell Membrane (Surface Area)(Surface Area)
Nutrients EnterNutrients Enter Waste And Products LeaveWaste And Products Leave The Amounts Of Nutrients Needed The Amounts Of Nutrients Needed
And The Amount Of Waste And The Amount Of Waste ProducedProducedDepends On The Cells VolumeDepends On The Cells Volume
Ratio of Surface Area To VolumeRatio of Surface Area To Volume
As Cell Size IncreasesAs Cell Size Increases Volume Increases More Volume Increases More Rapidly Than Surface Area Rapidly Than Surface Area (cell membrane)(cell membrane)
Cell Membrane Can Not Cycle Cell Membrane Can Not Cycle Nutrients and Wastes Fast Nutrients and Wastes Fast
Enough.Enough.
Cell DivisionCell Division
Cells DivideCells Divide
Before They BecomeBefore They Become
To LargeTo LargeCell Division Is The Process By Which A Cell Division Is The Process By Which A
Cell Divides Into Two Cell Divides Into Two Daughter CellsDaughter Cells
Cell DivisionCell Division
Before A Cell DividesBefore A Cell Divides
It Replicates Its DNAIt Replicates Its DNA
So Each Cell HasSo Each Cell Has
An Exact CopyAn Exact Copy
Chapter 10Chapter 10Cell Growth & DivisionCell Growth & Division
10-2 Cell Division10-2 Cell Division
ObjectivesObjectives
What are the main events of the cell What are the main events of the cell cycle?cycle?
What are the four phases of mitosis?What are the four phases of mitosis?
ChromosomesChromosomes
Carry Genetic Information From One Carry Genetic Information From One Generation of Cell to the Next Generation of Cell to the Next Generation of CellsGeneration of Cells
Made Up Of: Made Up Of:
DNA + ProteinDNA + Protein
ChromosomesChromosomes
Every Organism Has A Every Organism Has A Specific Number Of ChromosomesOf Chromosomes
Fruit Flys = 8Fruit Flys = 8
Carrots = 18Carrots = 18
Humans = 46Humans = 46
Giraffe = 30Giraffe = 30
King Crab = 208King Crab = 208
ChromosomesChromosomes
Not Visible Except During Not Visible Except During DivisionDivision
Well Before Division They Well Before Division They DuplicateDuplicate
ChromosomesChromosomes
ChromatidsChromatids Just Before Division Chromosomes Just Before Division Chromosomes
Condense Into Compact, Visible Condense Into Compact, Visible Structures Called Structures Called ChromatidsChromatids
CentromereCentromere Each Chromosome Has Two, Identical Each Chromosome Has Two, Identical
Chromatids Connected By A Chromatids Connected By A CentromereCentromere
ChromosomesChromosomesChromatid A
Chromatid A
Copy of Chromatid A
Copy of Chromatid A
Centromere
Microtubulesor
Spindle Fibers
Kenitophore
The Cell CycleThe Cell Cycle
Key ConceptKey Concept::
During The Cell CycleDuring The Cell Cycle: : A Cell GrowsA Cell GrowsPrepares For DivisionPrepares For DivisionDivides To Form Two Divides To Form Two Daughter CellsDaughter CellsEach Daughter Cell Then Each Daughter Cell Then Begins The Cycle AgainBegins The Cycle Again
Cell CycleCell Cycle
InterphaseInterphase
Time In-Between Time In-Between Cell DivisionsCell Divisions
Cell Division Cell Division oror M phase M phase
Events Of The Cell CycleEvents Of The Cell Cycle
InterphaseInterphaseMay Be Quite LongMay Be Quite Long
Divided Into 3 PartsDivided Into 3 Parts
The 3 Parts of InterphaseThe 3 Parts of Interphase
G1 PhaseG1 Phase
Cell Grows In SizeCell Grows In Size
Synthesize New Proteins & Synthesize New Proteins & OrganellesOrganelles
The 3 Parts of InterphaseThe 3 Parts of Interphase
S PhaseS Phase
Chromosomes Are Chromosomes Are ReplicatedReplicated
Once This Phase Begins The Once This Phase Begins The Cell Completes DivisionCell Completes Division
The 3 Parts of InterphaseThe 3 Parts of Interphase
G2 PhaseG2 Phase
Organelles & Proteins Organelles & Proteins Required For Mitosis Are Required For Mitosis Are ProducedProducedCell Is Now Ready To EnterCell Is Now Ready To Enter
M Phase (Mitosis)M Phase (Mitosis)
MitosisMitosis
Key ConceptKey Concept::Biologists Divide The Events Of Biologists Divide The Events Of
Mitosis Into Mitosis Into Four Phases:Four Phases:
1.1. ProphaseProphase
2.2. MetaphaseMetaphase
3.3. AnaphaseAnaphase
4.4. TelophaseTelophase
ProphaseProphase11stst & Longest & Longest
PhasePhase Chromosomes Chromosomes
Become Become VisibleVisible
CentriolesCentrioles Separate & Separate & Take Up Take Up Position On Position On Opposite Sides Opposite Sides Of The NucleusOf The Nucleus
SpindleSpindle Begins Begins To FormTo Form
ProphaseProphaseIn AnimalsIn Animals
Spindle Fibers Spindle Fibers Attach To Attach To Centromere On Centromere On Each ChromatidEach Chromatid
In PlantsIn PlantsNo Centromere, No Centromere,
Spindle Fibers Spindle Fibers Still Form From Still Form From CentrosomesCentrosomes
Late ProphaseLate Prophase Nucleolus Nucleolus
DisappearsDisappears
Nuclear Nuclear Envelope Envelope Breaks Breaks DownDown
MetaphaseMetaphaseShortShort
Just A Few MinutesJust A Few Minutes Chromosomes Chromosomes
Line Up Across Line Up Across Center Of The CellCenter Of The Cell
Microtubules Microtubules Connect The Connect The Centromere To Centromere To The Poles Of The The Poles Of The SpindleSpindle
AnaphaseAnaphase Centromeres Centromeres
SeparateSeparate Sister Sister
Chromatids Chromatids SeparateSeparate
Each Set Of Each Set Of Chromosomes Chromosomes Pulled To Their Pulled To Their PolesPoles
TelophaseTelophase
Chromosomes Chromosomes DisperseDisperse
New Nuclear New Nuclear Envelopes FormEnvelopes Form
Spindle Breaks Spindle Breaks ApartApart
Nucleolus Nucleolus ReformsReforms
CytokinesisCytokinesis There Are Now Two There Are Now Two
Nuclei In One CellNuclei In One Cell Cytokinesis Is The Cytokinesis Is The
Division Of The Division Of The Cytoplasm Into Cytoplasm Into Two CellsTwo Cells
The Cell Membrane The Cell Membrane Is Drawn Inward Is Drawn Inward Until The Cell Until The Cell Pinches Into Two Pinches Into Two Equal PartsEqual Parts
Cytokinesis In PlantsCytokinesis In Plants
A New Cell Plate A New Cell Plate Forms In The Forms In The Middle Of The Middle Of The Cell Which Cell Which Attaches To, And Attaches To, And Becomes Part Of, Becomes Part Of, The Cell WallThe Cell Wall
Chapter 10Chapter 10Cell Growth & DivisionCell Growth & Division
Section 10-3Section 10-3
Regulating Cell GrowthRegulating Cell Growth
ObjectivesObjectives
How is the cell cycle regulated?How is the cell cycle regulated?
How are cancer cells different from How are cancer cells different from other cells?other cells?
Controls On Cell DivisionControls On Cell Division
When Cells In Cell Cultures Come In When Cells In Cell Cultures Come In Contact With Each Other, They Contact With Each Other, They Stop Growing.Stop Growing.
Why?Why?
Controls On Cell DivisionControls On Cell Division
If A Hole Is Made In The Cell Culture, If A Hole Is Made In The Cell Culture, Cell Growth Will Restart & Continue Cell Growth Will Restart & Continue Until The Hole Is Filled.Until The Hole Is Filled.
Why?Why?
Controls On Cell DivisionControls On Cell Division
In Your Body The Rate Of Cell In Your Body The Rate Of Cell Growth Is ControlledGrowth Is Controlled..
Injury Causes Rapid Division Until Injury Causes Rapid Division Until The Wound Is Healed. Then The Wound Is Healed. Then Division Slows Again. Division Slows Again.
Why?Why?
Cell Cycle RegulatorsCell Cycle Regulators
Key ConceptKey Concept::
CyclinsCyclins Regulate The Timing Of The Regulate The Timing Of The Cell Cycle In Eukaryote Cells.Cell Cycle In Eukaryote Cells.Discovered In The 1980’sDiscovered In The 1980’sCyclins Are A Family Of Closely Cyclins Are A Family Of Closely Related Proteins That Rise & Fall Related Proteins That Rise & Fall Within The Cell With The Cell CycleWithin The Cell With The Cell Cycle
Cyclins & Cell CycleCyclins & Cell Cycle
Cell Cycle RegulatorsCell Cycle RegulatorsCyclinsCyclins
When Injected When Injected Into Non-Into Non-Dividing Dividing Cells, Cyclins Cells, Cyclins Cause Mitotic Cause Mitotic Spindles To Spindles To Form.Form.
Cell Cycle RegulatorsCell Cycle RegulatorsCyclinsCyclins
When Injected When Injected Into Non-Into Non-Dividing Dividing Cells, Cyclins Cells, Cyclins Cause Mitotic Cause Mitotic Spindles To Spindles To Form.Form.
Cell Cycle RegulatorsCell Cycle RegulatorsCyclinsCyclins
When Injected Into Non-When Injected Into Non-Dividing Cells, Cyclins Cause Dividing Cells, Cyclins Cause Mitotic Spindles To Form.Mitotic Spindles To Form.
Cell Cycle RegulatorsCell Cycle Regulators
Other Regulator Proteins Other Regulator Proteins Continue To Be FoundContinue To Be Found..
Other Internal RegulatorsOther Internal Regulators
These Proteins Respond To Events These Proteins Respond To Events Inside The Cell.Inside The Cell. Several Make Sure The Cell Does Several Make Sure The Cell Does
Not Enter Mitosis Until All Not Enter Mitosis Until All Chromosomes Have Been Chromosomes Have Been Replicated.Replicated.
Others Stop The Cell From Entering Others Stop The Cell From Entering Anaphase Until All Chromosomes Anaphase Until All Chromosomes Are Attached To The Mitotic SpindleAre Attached To The Mitotic Spindle
Cyclins & Cell CycleCyclins & Cell Cycle
External RegulatorsExternal Regulators
These Respond To Events These Respond To Events Outside The CellOutside The Cell
They Direct The Cell To Speed Up They Direct The Cell To Speed Up Or Slow Down The Cell CycleOr Slow Down The Cell Cycle
These Include These Include Growth FactorsGrowth Factors
Growth FactorsGrowth Factors
Very Active DuringVery Active During Embryonic DevelopmentEmbryonic Development Wound HealingWound Healing
Other External RegulatorsOther External Regulators
Molecules On The Cell Membrane Molecules On The Cell Membrane Of Neighboring Cells Slow The Of Neighboring Cells Slow The Growth ProcessGrowth Process They are like sensors that signal They are like sensors that signal
the cell to slow/stop growththe cell to slow/stop growth
Uncontrolled Cell GrowthUncontrolled Cell Growth
Uncontrolled Cell GrowthUncontrolled Cell Growth
Key Concept:Key Concept:Cancer Cells Do Not Cancer Cells Do Not
Respond To The Respond To The Signals That Signals That Regulate The Growth Regulate The Growth Of Most Cells. As A Of Most Cells. As A Result, They Form Result, They Form Masses Of Cells Masses Of Cells Called Tumors That Called Tumors That Can Damage Can Damage Surrounding Tissue.Surrounding Tissue.
Uncontrolled Cell GrowthUncontrolled Cell Growth
MetastasisMetastasisCancer Cells Cancer Cells
Break Break Loose From Loose From The Tumor The Tumor And Invade And Invade Tissues Tissues Throughout Throughout The BodyThe Body
SmokingSmoking
RadiationRadiation
Viral InfectionViral Infection
Some Carcinogen SourcesSome Carcinogen Sources
p53 Genep53 Gene
Usually Stops The Cell Cycle Usually Stops The Cell Cycle Until Chromosomes Have Been Until Chromosomes Have Been Properly Replicated.Properly Replicated.
High Percentage Of Cancers Cells High Percentage Of Cancers Cells Have Defects At This Gene SiteHave Defects At This Gene Site