Cell Growth & Cell Growth & ReproductionReproduction

Ch. 9Ch. 9

Surface Area:Volume Lab???Surface Area:Volume Lab???(See “Flinn Fax” in folder)(See “Flinn Fax” in folder)

OROR“Guess which pizza delivery boy will get “Guess which pizza delivery boy will get to his customer with the big fence the to his customer with the big fence the

fastest”fastest”

I. Why Must Cells Divide?...SIZE!I. Why Must Cells Divide?...SIZE!

A. The rate of diffusion limits _____A. The rate of diffusion limits _____

1. If a cell gets too big, it can’t 1. If a cell gets too big, it can’t receive nutrients and get rid of receive nutrients and get rid of wastes fast enoughwastes fast enough

a. Ex: A mitochondrion a. Ex: A mitochondrion that is 20 micrometers would that is 20 micrometers would have to wait 2 months to get have to wait 2 months to get nutrients!nutrients!

I. Why Must Cells Divide?...SIZE!I. Why Must Cells Divide?...SIZE!

B. _________ limits cell sizeB. _________ limits cell size

1. There must be enough DNA 1. There must be enough DNA to support the needs of the cell.to support the needs of the cell.

2. Some large cells have 2. Some large cells have multiple ______ to keep things multiple ______ to keep things running efficientlyrunning efficiently

I. Why Must Cells Divide?...SIZE!I. Why Must Cells Divide?...SIZE!C. Surface area-to-volume limits cell C. Surface area-to-volume limits cell

sizesize1. As a cell grows it’s volume 1. As a cell grows it’s volume (________) gets larger faster than (________) gets larger faster than the surface area (plasma the surface area (plasma membrane)membrane)

a. See Figure 8.9 on pg. a. See Figure 8.9 on pg. 2022022. There is not enough surface area 2. There is not enough surface area available to let nutrients in and available to let nutrients in and wastes outwastes out

II. Cell Reproduction (Division)II. Cell Reproduction (Division)

A. Remember all cells come from A. Remember all cells come from preexisting cells (Cell Theory)preexisting cells (Cell Theory)

B. Cells constantly need to divide toB. Cells constantly need to divide to

________________________________________________________

II. Cell Reproduction (Division)II. Cell Reproduction (Division)

C. C. ChromosomesChromosomes- Cell structure that - Cell structure that carries genetic materialcarries genetic material

1. Composed of DNA wrapped 1. Composed of DNA wrapped around ____________around ____________

2. Appear right before cell division 2. Appear right before cell division occurs (Condensed)occurs (Condensed)

a)a)______________________ refers to the refers to the uncondensed form of the uncondensed form of the chromosomechromosome

II. Cell Reproduction (Division)II. Cell Reproduction (Division)

3. 2 3. 2 sister chromatidssister chromatids are held together by a are held together by a

______________________________

a. Each a. Each chromatid chromatid is is identicalidentical

III. Cell CycleIII. Cell Cycle

Click for Animation

III. Cell CycleIII. Cell Cycle

A. A. Cell CycleCell Cycle- Sequence of growth - Sequence of growth and ________ of a cell.and ________ of a cell.

““__ __ __ __ __ __”__ __ __ __ __ __”

B. OverviewB. Overview

1. Interphase1. Interphase

2. Mitosis (PMAT)2. Mitosis (PMAT)

3. Cytokenesis3. Cytokenesis

III. Cell CycleIII. Cell Cycle

C. InterphaseC. Interphase

1. Rapid growth & metabolism 1. Rapid growth & metabolism (G1)(G1)

2. DNA replication (S)2. DNA replication (S)

3. __________ replicate in 3. __________ replicate in preparation for cell division preparation for cell division (G2)(G2)

III. Cell CycleIII. Cell Cycle

D. Mitosis (PMAT)D. Mitosis (PMAT)1. Prophase (“1. Prophase (“CCan an NNemo emo SSwim?”)wim?”)

a. a. ________________________ condensecondenseb. b. NNuclear envelope and uclear envelope and nucleolus disintegratenucleolus disintegratec. c. ______________________ form in form in

between between centriolescentrioles at opposite at opposite sides of the cell.sides of the cell.

III. Cell CycleIII. Cell Cycle

D. Mitosis (PMAT)D. Mitosis (PMAT)

2. Metaphase2. Metaphase

a. Spindle fibers attach a. Spindle fibers attach to centromeres of the to centromeres of the ______________________________

b. Chromosomes are b. Chromosomes are pulled to the pulled to the MMiddle of the celliddle of the cell

III. Cell CycleIII. Cell Cycle

D. Mitosis (PMAT)D. Mitosis (PMAT)

3. Anaphase (Ana & Fay)3. Anaphase (Ana & Fay)

a. The sister a. The sister chromatids are pulled apart to chromatids are pulled apart to opposite sides of the cell by opposite sides of the cell by the ___________ ________the ___________ ________

III. Cell CycleIII. Cell Cycle

D. Mitosis (PMAT)D. Mitosis (PMAT)4. Telophase4. Telophase

a. Prophase in reverse!a. Prophase in reverse!b. The spindle fibers b. The spindle fibers

__________________________c. The chromosomes c. The chromosomes

uncoiluncoil

III. Cell CycleIII. Cell Cycle

D. Mitosis (PMAT)D. Mitosis (PMAT)

4. Telophase4. Telophase

d. 2 new nuclear d. 2 new nuclear envelopes appear around the envelopes appear around the ______________________________________

5. Only the nucleus has 5. Only the nucleus has divided, not the entire celldivided, not the entire cell

III. Cell CycleIII. Cell Cycle

E. E. ______________________- The process in - The process in which the cytoplasm (cell) which the cytoplasm (cell) dividesdivides1. Animal cells pinch off to 1. Animal cells pinch off to form _ new cellsform _ new cells2. Plant cells form a cell plate 2. Plant cells form a cell plate then _ new cell walls form on then _ new cell walls form on either side of the plateeither side of the plate

III. Cell CycleIII. Cell Cycle

F. The two new cells go back to F. The two new cells go back to ___________ to start the ___________ to start the cycle over again.cycle over again.

G. Result: 2 Cells identical to G. Result: 2 Cells identical to each othereach other

RECAPRECAP

-What are the 3 reasons cells -What are the 3 reasons cells need to divide?need to divide?

-What are the stages of the cell -What are the stages of the cell cycle? What happens in cycle? What happens in each?each?

-What are the 4 phases of -What are the 4 phases of miosis? What happens in miosis? What happens in each?each?

RECAPRECAP

-What happens during -What happens during cytokenesis?cytokenesis?

-What do you start and end with -What do you start and end with at the beginning and end of at the beginning and end of the cell cycle?the cell cycle?