Station 5 - Cell Cycle

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Reporting Category 1
Cell Structure and
Function
Station 5
Cell Cycle
Bell Ringer - Essential Question
What happens to a eukaryotic cell that does
not complete all stages in the cell cycle?
The cell may enter the GO phase and remain
there until the cell reenters the cell cycle. If it
passes the GO phase and remains in the cycle,
the cell may destroy itself if the DNA has not
replicated correctly or the chromosomes fail to
separate properly in metaphase. If the cell does
not destroy itself, it may become cancerous.
Pre-Review Question
• When a cell divides to make and exact
copy of itself it is called…
• A. Meiosis
• B. Bitosis
• C. Mitosis
• D. Taxonomy
Pre-Review Question
• What are the stages of the cell cycle?
•
•
•
•
•
•
Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
Pre-Review Questions
• What is the longest phase of the cell
cycle?
•
•
•
•
•
•
Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
You will now go back to the lab
to complete todays activities.
Using the Cycle Characteristics Cards below, determine which
section of the Cell Cycle (next slide) each card belongs.
Once you
have placed
them in the
correct order,
sketch and
name the
cycle phases
in your
journal.
Then add the
descriptions.
Check your answers.
2. Discuss with your partner:
What must happen to a eukaryotic cell before it
can go from the G1 phase to the S phase?.
The cell must grow and conduct normal cell
activities in preparation for the
replication of the DNA. Certain cell components,
such as the centrosomes, duplicate.
3. Discuss with your partner:
What happens to a cell in the GO phase?
It may remain in the GO phase and carry out
normal functions. It can be stimulated to reenter the
cycle if needed or it may be terminated.
4. Discuss with your partner:
What happens at the G1/S and the G2/M
checkpoints?
• The G1/S checkpoint confirms the presence of
all necessary conditions, such as nutrients and
enzymes required for DNA replication. If the
conditions are not favorable for DNA replication,
the cell is arrested in the cycle.
• The G2/M checkpoint confirms that the DNA has
been replicated correctly and is ready to go
through mitosis and cytokinesis.
5. With your partner, arrange the Phases of
Eukaryotic Mitosis and Cytokinesis cards in the
order they follow during cell division. Next, remove
the Plant and Animal Cell Mitosis and Cytokinesis
cards from their envelope and match them to the
correct stages.
Use these to help you draw your sketches for
question 1.
6. With your partner,
look at the Mitosis in an
Onion Root Tip sheet.
This sheet shows cells
in various stages of
mitosis. Count the
number of cells in each
phase of mitosis.
Compare your answers
with the next slide.
6.
Compare your answers
7. Discuss with your partner:
Which phase showed the largest number of active
cells? Explain why this phase, of all the phases,
would most likely have the most abundant number
of active cells.
Interphase has the largest number of active cells.
Cells in an organism are dividing only when the
organism needs to replace damaged cells or when
the organism is actively growing. The necessary
resources must be available before mitosis can
begin again.
9. Discuss with your partner:
Cancer can occur in any of the more than 200
types of cells in the human body. During which
phase(s) of the cell cycle is a cancer cell most
likely to develop?
Cancer cells can occur in any of the phases of the
cell cycle – G1, S, or G2.
10. Discuss with your partner:
Explain what can happen to a cell that can cause it
to become a cancer cell.
There are genes that tell the cell how fast to divide
and when to stop. If these genes are mutated, the
mutation can cause the cell cycle to go too fast—
like running down hill too fast to be able to stop.
The cancer cells divide too quickly and pile up in
one area— this is called a tumor.
11. Discuss with your partner:
What is the relationship between mitosis and
growth in an organism?
Mitosis is the process that enables an organism to
grow. Growth is the physical increase in size and
weight of an organism over a period of time. As
cells divide and grow to maturity in G1, they cause
the organism to physically grow.
I need to remember………
• The cell cycle is a continuous process of cell
growth and reproduction.
• The cell cycle goes through interphase, the
longest phase, before undergoing mitosis and
cytokinesis.
• A cancer cell can develop during any part of
interphase. A cancer cell is a cell that goes
through the cell cycle continuously, never
stopping in G0. These cells consume the body’s
resources.
• Growth results from mitosis.
• There are checkpoints during the cell cycle to help
cells divide correctly.
Post-Review Questions
A
B
C
D
E
• Name the
phase for each
cell.
• Prophase
• Interphase
• Anaphase
• Telophase
• Metaphase
Post-Review Questions
• All the following are part of Mitosis
except…
•
•
•
•
•
Interphase
Prophase
Metaphase
Anaphase
Telophase
Post Review Question
• Cancer cells can occur when cells fail to
go into….
•
•
•
•
A.
B.
C.
D.
G1
G2
G3
G0
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