1. Where it all began…
You started as a cell smaller than a period at the end of a sentence…

2. Getting from there to here…
Going from egg to baby….
the original fertilized egg has to divide…
and divide…

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4. What types of cells divide?
Prokaryotes: organisms include Bacteria
Eukaryotes :Plants & animals
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5. Key characteristics of Prokaryotes
Lack a nucleus
Have a single chromosome
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6. Steps in Binary Fission
Bacteria reproduce by BINARY FISSION
3 steps in Binary Fission:
Cells increase their cell mass slightly
DNA & cell components are replicated
Each cell divides into 2 daughter cells
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7. Binary Fission of Bacterial Cell
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8. E. Coli Dividing by Binary Fission--SIMPLE
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9. Remember this slide? Not so easy for Eukaryotes
Going from egg to baby….
the original fertilized egg has to divide…
and divide…

10. Why do cells divide… One-celled organisms for reproduction
asexual reproduction (clones)
Multi-celled organisms
for growth & development
from fertilized egg to adult
for repair & replacement
replace cells that die from normal wear & tear or from injury
amoeba
Unicellular organisms
Cell division = reproduction
Reproduces entire organism& increase population
Multicellular organisms
Cell division provides for growth & development in a multicellular organism that begins as a fertilized egg
Also use cell division to repair & renew cells that die from normal wear & tear or accidents
starfish

11. Cell Cycle: Seasons of a cell
Stages in growth & division
G1 Stage
S Stage
G2 Stage
M Phase
Cytokinesis
Interphase
(circle & label on notetaker)
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G1 Stage
G1 means first growth stage
2 processes that occur in G1:
Cell increases in size
Cell prepares to copy its DNA
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S Stage:
Synthesis: making more
DNA is copied in this stage
What is this process called?
What enzymes are involved?
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14. DNA must be duplicated…
chromosomes in cell
4 single-stranded chromosomes
nucleus
cell
DNA in chromosomes
nucleus
cell
duplicated chromosomes
duplicated
chromosomes
4 double-stranded chromosomes

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G2 Stage
2nd growth stage
Time between DNA synthesis and mitosis
Cell continues growing during G2
Makes proteins that will be needed for mitosis and cell division
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16. Why do cells divide… for growth & development for repair & replacement
from fertilized egg to adult
for repair & replacement
replace cells that die from normal wear & tear or from injury
Unicellular organisms
Cell division = reproduction
Reproduces entire organism& increase population
Multicellular organisms
Cell division provides for growth & development in a multicellular organism that begins as a fertilized egg
Also use cell division to repair & renew cells that die from normal wear & tear or accidents
starfish

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Interphase
Resting Stage
Cells carrying on normal activities
Kidney cells filtering blood
Skin cells replacing old skin cells
Occurs before mitosis
Chromosomes aren’t visible
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Interphase
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19. Do you get it? (aka: checking for understanding)
Agree to Disagree
Partner A prompt: “At first I thought cell division meant…now I know cell division’s function is…”
Partner B in ONE MINUTE:
Paraphrases (NOT repeats) 1st person’s idea
Tells what they agree with
Tells what they disagree with
Tells their idea.

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Stages of Mitosis
Prophase
Metaphase
Anaphase
Telophase
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21. Cells Undergoing Mitosis
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Steps in Prophase
Nuclear membrane disappears
Spindle fibers (rope-like proteins) begin to form from specialized organelles responsible for cell division
DNA coils tightly & becomes visible as chromosomes
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Prophase
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Human Chromosomes
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Steps in Metaphase
Spindle fibers attach to each side of the copied chromosome
Preparation for separating chromosomes
Cell aligns its chromosomes in the middle of the cell
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Metaphase
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27. Do you get it? (aka: checking for understanding)
Partner A: Explain what happens to a cell in Prophase (picture A)
Partner B: Rephrase what your partner said for Prophase (picture A) and explain what happens to a cell in Metaphase (picture B)
Partner A: Rephrase what your partner said for Metaphase (picture B)

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Steps in Anaphase
Cell chromosomes are separated (pulled apart)
Spindle fibers (ropes) shorten so chromosomes pulled towards the sides of cell
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Anaphase
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Steps in Telophase
Separation of chromosomes completed and found on either side of the 2 cells
Nucleus reform
Chromosomes uncoil
Cell Plate forms in plants Cleavage furrow forms in animals
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Telophase
       Plant            
Animal
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Video
THE BASICS OF BIOLOGY
You tube video clip:
Eukaryotic Cell Cycle
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Cytokinesis
Division of the Cytoplasm
Follows mitosis
Forms two, identical daughter cells
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Cytokinesis
Cell Plate Forming in Plant Cells
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35. Mitosis in plant cell
Partner A: summarize the cell cycle focusing on the chromosomes
Partner B: summarize the cell cycle focusing on the everything but the chromosomes

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THE CELL CYCLE!!!!
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CONCEPT MAP
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38. Amoeba Sisters Pt 1 & 2 (w/ Questions)
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