Download Cell Division*Mitosis

Cell Cycle
Bits and Bobs
Miss B NNHS
[email protected]
biologymissb
@biologymissb
NNHSmissb.weebly.com
Boston College
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Private college located in
Chestnut Hill
9000 undergraduates and
4500 graduate students
Ranked as in top 35 by
Forbes as best
undergraduate schools in
the US
Lynch School of Education,
Connell School of Nursing,
BC Law School, Carroll
School of Management
2014-2015 Tuition & Fees
$47,436
Students
9,049 enrolled
46% male / 54% female
Admissions
Jan. 1 application
deadline
32.2% accepted
Cell Cycle vs
Cell Division
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Cell Division is how unicellular organisms
reproduce
Cell division is one part of the cell cycle
Multicellular organisms depend on the cell cycle
to reproduce
How do Eukaryotic
Cells Regulate Division
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Cyclin-dependent kinases
(Cdks) are regulatory
proteins that work within the
cell cycle.
Part of the cell cycle control
system
Check points throughout cell
cycle, (after G1 and G2) to
ensure the cell is ready to
divide
G0
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Along with G1 and G2 there is another “gap/growth”
phase known as G zero
Resting phase within cell cycle
Cell is not dividing nor is it preparing to divide
Why don’t
Neurons Divide?
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Cells such as heart muscle
cells and neurons do not
divide once they reach
maturity
These cells develop from
stem cells, then will remain
in G0 or a “quiescent”
state until they have
served there time
Then they will undergo
apoptosis
Apoptosis
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Programmed cell death or cell suicide
Occurs when cell is no longer needed or becomes a
threat to the organism (ie infection)
Billions of cells in your intestines are dying each hour
https://www.youtube.com/watch?v=qjjHKDn12qI
Cancer Biology
Miss B NNHS
[email protected]
biologymissb
@biologymissb
NNHSmissb.weebly.com
What is Cancer?
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Cell cycle is not regulated during cancer
Cells excessively divide and invade other
tissues
Do not have Cdks
Benign Tumor
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When abnormal cells remain at the original
site.
Malignant Tumor
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Cells whose genetic changes enable them to
spread into new tissues
Impair the functions of one or more organs
An individual with a malignant tumor is said to
have “cancer”
https://www.youtube.com/watch?v=8LhQllh46yI