Download 10-2 Cell Division

Chapter 10
Cell Growth and Division
Vocabulary

Word Sort
Largest Cell?
Largest Cell?
Giant Squid – Nerve Cells Up to 36 Feet!
Section 10-1 Cell Growth
What problems does growth cause for cells?
I. Limits to cell growth
1. Why do cells divide rather than continue to
grow indefinitely?
2. DNA Overload
3. Exchanging Materials
Section 10-1 Cell Growth
What problems does growth cause for cells?
I. Limits to cell growth
1. Why do cells divide rather than continue to
grow indefinitely?
larger
a. The ___________
the cell is the more
DNA
demands are placed on the cell’s _____
b. Its more difficult to move enough
____________
and ___________
across the
wastes
nutrients
cell membrane
Section 10-1 Cell Growth
What problems does growth cause for cells?
I. Limits to cell growth
2. “DNA Overload”:
Cell function
a. DNA controls_______________
; found in
nucleus of eukaryotes
b. DNA meets the needs of the cell when the
small
cell is_________,
however as the cell
increases in size, the DNA cannot meet its
Information Crisis
needs anymore  “_____________”
Section 10-1 Cell Growth
What problems does growth cause for cells?
I. Limits to cell growth
3. Exchanging Materials:
Food
oxygen
water
a. ________,
_________,
and _______
enter a cell through its cell membrane.
Waste Products leave the same
b. _____________
way.
c. Rate of this exchange depends on the
surface area to volume ratio
Section 10-1 Cell Growth
What problems does growth cause for cells?
II. Surface Area to Volume Ratio
1. To obtain the ratio of surface area to volume,
__________
the surface area by the volume.
divide
Cell Sizes
Surface Area
lengthxwidthx6
Volume
Lengthxwidthxheight
Ratio of surface
area to volume
6 cm2
24
54 cm2
cm2
27cm3
1 cm3
6:1
8 cm3
3:1
2:1
Section 10-1 Cell Growth
What problems does growth cause for cells?
•II. Surface Area to Volume Ratio
increases much more rapidly
• Notice that volume _________
than surface area.
surface area to volume
• This causes the ______________________
ratio to decrease which is a serious problem for
_________________,
the cell.
Too large it makes it more difficult to
• As cells get _________
get sufficient amounts of oxygen and nutrients in and
waste products out.
Section 10-1 Cell Growth
What problems does growth cause for cells?
Question: How does an organism get bigger
if the cells that it is made of do not get
larger?
It grows more cells.
Answer: _____________________
Section 10-1 Cell Growth
What problems does growth cause for cells?
III. Division of the Cell
1. Before the cell gets too large it divides into
daughter cells
two “_________”
Section 10-1 Cell Growth
What problems does growth cause for cells?
III. Division of the Cell
Cell division
2. The process is called ___________________.
Cell division solves the problem of cells getting
Increasing size while
too large by _______________
reducing volume
__________________
(more small cells instead
of one large cell)
Section 10-1 Cell Growth
What problems does growth cause for cells?
III. Division of the Cell
replicates
3. Before cell division, the cell ____________,
or
copies, its entire DNA.
This solves the problem of
information storage
___________________
because each
daughter cell gets a complete set of
genetic
__________
information
Section 10-1 Cell Growth
What problems does growth cause for cells?
III. Division of the Cell
4. Each cell has an increase in ratio of surface
area to volume that allows for more efficient
exchange
of materials with the environment.
__________________
IQ # 1 10.1-10.2
1. Why is it advantageous to have smaller cells
as opposed to larger cells?
2. Explain “DNA Overload”?
3. Draw a chromosome and label its parts.
4. Define Mitosis. What is the difference
between Mitosis and Cell Division?
Agenda
• IQ # 1 & Check Homework
• Lecture and Discussion 10.2
• Overhead Drawings
• Homework – 10.1 Section Assessment
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
All cell division must involve the replication of DNA before cell
division so the genetic information can be transferred to the
daughter cells.
In Prokaryotes the rest of cell division is simply to
__________________.
divide
the contents
In Eukaryotes the division is more complex it occurs in two
stages:
division of the nucleus
a.
Mitosis: ________________________
b.
______________:
Cytokinesis division of the cytoplasm
WHY ARE THEY DIFFERENT?
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
Unicellular organisms use mitosis and
reproduce
cytokinesis to ________________.
asexual
This is a type of _______________
reproduction producing two identical daughter
one
cells from ______
identical parent cell.
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
Multicellular organisms use mitosis and
add new cells to the organism
cytokinesis to _________________________
____________________________
for growth and development
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
I. Chromosomes
DNA and
1. Chromosomes are composed are ______
proteins (histones) and carry the genetic
__________
information in eukaryotic cells.
a.
Each species of organism has a _________
specific
________
number of chromosomes.
8
1.
Drosophila melanogaster (Fruit Fly) has ___
chromosomes
46 chromosomes
2.
Humans have ____
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
I. Chromosomes
Not visible except
b. Chromosome are ___________
chromatin
during cell division. (known as ___________
when not dividing)
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
I. Chromosomes
c. Replication (copying) of the DNA occurred
before cell division
_______________________
therefore every
sister
chromosome is actually two identical “______”
chromatids
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
I. Chromosomes
d. Pair of chromatids
centromere
connected to each other ___________,
usually located near the center of the
chromosome.
centromere
Sister
chromatids
http://www.biostudio.com/demo_freeman_dna_coiling.htm
Chromosome Drawing
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
II. The Cell Cycle
1.Cell Cycle: the series of events the cell
goes through as they ________________
grow and divide
separated by periods of “in-between” time
called ___________.
interphase
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
II. The Cell Cycle
grows
2. During the cell cycle the cell ________,
division
prepares for __________,
and divides to form two
daughter cells, each of which then
begins the cycle again
__________________________.
Four phases of the cell cycle
3. _______
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
III. Events of the Cell Cycle
cell growth increase in size
a. G1 phase: __________,
and ______________
new proteins and
synthesize
organelles.
b. S phase: chromosome __________
replication
(synthesis)
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
III. Events of the Cell Cycle
c. G2 phase: shortest of the phases,
organelles and molecules required for
___________
cell division are produced.
mitosis
cytokinesis
d. M Phase: _________and
____________
G1, S, and G2 are all taking place during
interphase : the phase between
____________
divisions.
Cell Cycle Drawing
Agenda
• Lecture and Discussion 10.2
• Overhead Drawings
• Homework – 10.2 Section Assessment
G1
M-phase
s
G2
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
I. Mitosis
a. The mitotic phase can be sub-divided into four
metaphase
prophase
phases ______________,
_____________,
_____________
and _____________
(PMAT).
anaphase
telophase
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
I. Mitosis
nuclear
b. Mitosis is strictly _____________
division.
Difference between Cell Division and Mitosis?
c. Mitosis is followed by cytoplasmic division,
cytokinesis
or ___________,
to complete cell division
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
I. Mitosis
d. Mitosis results in two “daughter cells”,
identical to each other, and is
which are ________
used for growth and asexual reproduction.
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
I. Mitosis
e. The growth and synthesis phases are
Interphase
collectively called _________
(i.e. in between cell division).
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
I. Mitosis
f. The only source of genetic variation in the
cells is via __________.
mutations
How do mutations form?
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
Interphase
Stage
between
division
 This is when the cell is not
dividing, but is carrying out its
normal
cellular functions
____________________.
is not visible
 Chromatin _____
 DNA
_____, histones and
centrioles all replicated
 Replication of
______________
cell organelles e.g.
mitochondria, occurs in the
cytoplasm.
 G1, S and G2 phases are
occurring
10-2 Cell Division
What are the main events of the cell
cycle? What are the phases of mitosis?
Prophase
Beginning
of mitosis
(nuclear
division)
•
chromosomes ___________
condense and
become ___________.
visible
•
Due to DNA replication during
interphase, each chromosome consists
of two identical sister
______________
chromatids connected at the
____________
centromere
•
opposite
centrioles move to _________
poles of cell (in animal cells)
•
Nucleolus ______________
disappears
•
Spindle fibers (microtubules) begin
to form and ___________
attachto
chromosomes near the centromere
•
Phase ends with the breakdown of
the _________________
nuclear envelope
10-2 Cell Division
Metaphase
(middle)
Spindle fibers (microtubules)
centrioles
connect ______________
to
chromosomes
Chromosomes align along
equator
___________of
cell.
Anaphase
chromosome
separate
Centromeres _______,
split
allowing sister chromatids to
________________
separate
Chromatids move towards
opposite
__________
poles, centromeres first,
creating a “V” shape
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
Telophase
New
nuclei form
Spindle fibers
disperse
____________
_________________
Nuclear membrane
form around each set
of chromatids
Nucleoli
___________
reform
End of nuclear
division
10-2 Cell Division
What are the main events of the cell cycle? What are the phases of mitosis?
•Asexual reproduction is the production of offspring from a single
parent using mitosis.
•The offspring are therefore genetically identical to each other and
to their “parent”- in other words they are clones.
•Asexual reproduction is very common in nature, and we humans have
developed artificial methods.
•The Latin terms in vivo (“in life”, i.e. in a living organism) and in vitro (“in
glass”, i.e. in a test tube) are often used to describe natural and artificial
techniques.
Centrioles
Centrioles
Centromere
Nuclear
envelope
Daughter
Cells
Chromatin
Centrioles
Chromosomes
_______________
(paired chromatids)
Spindle
Centrioles
Individual
Chromosomes
Nuclear
envelope
reforms
http://highered.mcgraw-hill.com/sites/0072437316/student_view0/chapter11/animations.html#
Animal Cell Division in White Fish Blastula
10-2 Cell Division
V. Cytokinesis:
cytoplasm
a. Division of the ________________
b. End of the __________
Cell cycle
c. Production of two ______________
daughter cells
identical
plants
d. Different in _________
and _________
cells
animals
Cell plate
forming
Wall of
parent cell
Daughter
nucleus
Cleavage
furrow
Cleavage
furrow
Contracting ring of
microfilaments
Daughter cells
Cell wall
Vesicles containing
cell wall material
New cell wall
Cell plate
Daughter
cells
10-2 Cell Division
Cytokinesis
Cytoplasmic
division
New
daughter
cells form
In animal cells a
cleavage furrow forms,
_______________
which splits the cell in two.
In plant cells vesicles
move to the equator, line
up and fuse to form two
membranes called the
cell plate
__________.
A new
_________
cell wall is laid down
between the membranes,
which fuses with the
existing cell wall.
Agenda

Review Quizzes
Review Cancer Project and Answer Questions
Begin 10.3 Lecture

Homework: 10.3 Section Assessment


10-3 Regulating the Cell Cycle
Key Concepts: How is the cell cycle regulated? How are cancer cells
different from other cells?
______________
organisms control cell growth
Multicellular
and division very carefully
-way to increase number of cells and size of
organism
F.Y.I. In different cell types the cell cycle can last
from hours to years. For example bacterial cells
can divide every 20-30 minutes under suitable
conditions, skin cells divide about every 12 hours
on average, liver cells every 2 years, brain and
muscle cells do not divide.
10-3 Regulating the Cell Cycle
Key Concepts: How is the cell cycle regulated? How are cancer cells
different from other cells?
replacement
This provides the _______________
of cells
wear out or are broken down
that ________________________.
I. Controls on Cell Division:
1. Cells in a ________________
will continue to divide
petri dish
until they come into ___________
with other cells.
contact
2. Then the cells ________
stop _____________
dividing
3. Cells are ______________
from the center of the
removed
dish.
4. Then the cells _______________
the open space
bordering
will begin dividing.
5. Until they have _______
the empty space.
filled
6. The controls for cell growth and division can be
___________________.
turned on and off
7. We can see the same thing happen in our
__________________.
own bodies
3.
1.
5.
2.
4.
Question: What happens when you cut your finger or
break your bone?
Answer: The cells bordering the injury will begin
dividing to fill in the gap in the tissues that
have been torn or broken. This is the process
known as healing.
II. Cell Cycle Regulators
1. Scientists wondered what ____________cell
controlled
division.
2. Tim Hunt and Mark Kirschner discovered
that cells in mitosis contained a protein that
when injected into a cell would cause the
formation of spindle fibers.
3. Protein group known as ____________
cyclins
regulates the cell cycle.
4. They rise and fall in time with the ________.
cell cycle
regulate
5. Cyclins _____________
the timing of the
eukaryotic
cell cycle in __________cells.
a. Two main groups of protein regulators
1. Internal Regulators: respond to events
__________________
.
inside the cell
Ex. Make sure cell doesn’t enter
mitosis until chromosomes have all
replicated
2. External Regulators: respond to events
outside the cell
_________________________.
Ex. Embryonic growth and healing
III. Uncontrolled Cell Growth
A. Cancer
1. Cell Growth is so controlled because when it
is not controlled things go very, very______.
wrong
2. _________
is a disorder in which some of
Cancer
the body’s own cells lose the ability to
control growth.
3. Cancer cells do not respond to the
_____________that
regulate the growth of
signals
most cells.
4. When cells divide ___________________
uncontrolled
they form masses of cells called __________
tumors
that can damage the surrounding tissue.
5. Cancer cells can break off and
_____________
throughout the body
spread
disrupting normal activities and causing
serious medical problems or even death.
B. Causes of Cancer
1. Smoking ____________
tobacco
2. _____________
exposure
Radiation
Viral Infection
3. ______________
4.____________
defect in gene p53
Genetic
C. Cancer is a disease of the __________.
cell cycle