1. Cell Growth and Division
Chapter 10
Cell Growth and Division

2. Section 10-1 Cell Growth Key Concept: What problems does growth cause for cells?
I. Limits to cell growth
1. Why do cells divide rather than continue to grow indefinitely?
a.      The ___________ the cell is the more demands are placed on the cell’s _____
b.      Its more difficult to move enough ____________ and ___________ across the cell membrane
2. “DNA Overload”:
a. DNA controls_____ __________ ; found in nucleus of eukaryotes
b. DNA meets the needs of the cell when the cell is_________, however as the cell increases in size, the DNA cannot meet its needs anymore  “______________ _________”
larger
DNA
nutrients
wastes
cell
function
small
Information
crisis

3. 3. Exchanging Materials:  
a. ________, _________, and _______ enter a cell through its cell membrane.
b. ________ _________ leave the same way.
  c. Rate of this exchange depends on the surface area to volume ratio
II. Surface Area to Volume Ratio
1. To obtain the ratio of surface area to volume, __________ the surface area by the volume.
Food
oxygen
water
Waste
products
divide

4. Cell Sizes Surface Area Volume 54 cm2 6 cm2 24 cm2 27cm3 1 cm3 8 cm3
lengthxwidthx6
54 cm2
6 cm2
24 cm2
Volume
Lengthxwidthxheight
27cm3
1 cm3
8 cm3
Ratio of surface area to volume
6:1
3:1
2:1

5. Notice that volume _____________ much more rapidly than surface area. 
This causes the ______________________
_________________, which is a serious problem for the cell. 
As cells get _____ _________ it makes it more difficult to get sufficient amounts of oxygen and nutrients in and waste products out.
Question: How does an organism get bigger if the cells that it is made of do not get larger?
 Answer: _____________________
increases
surface area to volume
ratio to decrease
too
large
It grows more cells.

6. III. Division of the Cell
1.  Before the cell gets too large it divides into two “_____________” cells
2. The process is called ________ _______________.
Cell division solves the problem of cells getting too large by _______________ while __________________ (more small cells instead of one large cell)
daughter
cell
division
Increasing size
reducing volume

7. 3. Before cell division, the cell ____________, or copies, its entire DNA.
  a. This solves the problem of ___________________ because each daughter cell gets a complete set of __________ information
4. Each cell has an increase in ratio of surface area to volume that allows for more efficient __________________ with the environment.
replicates
information storage
genetic
exchange of materials

8. division of the nucleus Cytokinesis
10-2 Cell Division Key Concepts: What are the main events of the cell cycle? What are the four 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 __________________.
In Eukaryotes the division is more complex it occurs in two stages:
a.      Mitosis: ________________________
b.      ___________: division of the cytoplasm
divide the contents
division of the nucleus
Cytokinesis

9. Unicellular organisms use mitosis and cytokinesis to ________________.
This is a type of _______________ reproduction producing two identical daughter cells from ______ parent cell.
Multicellular organisms use mitosis and cytokinesis to _________________________
____________________________
reproduce
asexual
one
add new cells to the organism
for growth and development

10. I. Chromosomes
1.     Chromosomes are composed of ______ and __________ (histones) and carry the genetic information in eukaryotic cells.
a.      Each species of organism has a _________ ________ of chromosomes.
1.      Drosophila melanogaster has ___ chromosomes
2.      Humans have ____ chromosomes
DNA
proteins
specific
number 8 46

11. b. Chromosomes are ____ __________ except during cell division
b.    Chromosomes are ____ __________ except during cell division. (known as ___________ when not dividing)
c.    Replication (copying) of the DNA occurred _______________________ therefore every chromosome is actually two identical “______” chromatids
d. Each pair of chromatids is connected to each other at an area called the ___________, usually located near the center of the chromosome.
not
visible
chromatin
before cell division
sister
centromere

12. centromere Sister chromatids

13. II.  The Cell Cycle
1.Cell Cycle: the series of events the cell goes through as they ________________ separated by periods of “in-between” time called ___________.
2. During the cell cycle the cell ________, prepares for __________, and divides to form two daughter cells, each of which then __________________________.
3. _______ phases of the cell cycle
grow and divide
interphase
grows
division
begins the cycle again
Four

14. III. Events of the Cell Cycle 
a. G1 phase: __________, increase in size and ______________ new proteins and organelles.
b. S phase: chromosome __________ (synthesis)
c. G2 phase: shortest of the phases, organelles and molecules required for ___________ are produced.
d. M Phase: _________and ____________
G1, S, and G2 are all taking place during ____________ : the phase between divisions.
cell growth
synthesize
replication
cell division
mitosis
cytokinesis
interphase

15. G1
M-phase s G2

16. III. Mitosis
a. The mitotic phase can be sub-divided into four phases ______________, _____________, _____________ and _____________ (PMAT).
b. Mitosis is strictly _____________ division.
c. Mitosis is followed by cytoplasmic division, or
___________, to complete cell division
prophase
metaphase
anaphase
telophase
nuclear
cytokinesis

17. d.      Mitosis results in two “daughter cells”, which are ________ to each other, and is used for growth and asexual reproduction.
e.     The growth and synthesis phases are collectively called interphase (i.e. in between cell division).
f. The only source of genetic variation in the cells is via ________________.
identical
mutations

18. Stage between division
Interphase
Stage between division
·  This is when the cell is not dividing, but is carrying out its ____________________.
· Chromatin _____ visible
·    _____, histones and centrioles all replicated
· Replication of ______________ like mitochondria, occurs in the cytoplasm.
· G1, S and G2 phases are occurring
normal cellular functions
is not
DNA
cell organelles

19. condense visible chromatids centromere opposite disappears attach
Prophase
Beginning of mitosis
(nuclear division)
· chromosomes ___________ and become ___________.
· Due to DNA replication during interphase, each chromosome consists of two identical sister ______________ connected at the ____________
· centrioles move to _________ poles of cell (in animal cells)
· Nucleolus ______________
· Spindle fibers begin to form and ___________ to chromosomes near the centromere
· Phase ends with the breakdown of the _________________
condense
visible
chromatids
centromere
opposite
disappears
attach
nuclear membrane

20. Spindle fibers connect ______________ to chromosomes
Metaphase
(middle)
Spindle fibers connect ______________ to chromosomes
Chromosomes align along ___________of cell.
Anaphase
chromosome separate
Centromeres _______, allowing sister chromatids to ________________
Chromatids move towards __________ poles, centromeres first, creating a “V” shape
centrioles
equator
split
separate
opposite

21. Spindle fibers ____________ ________________
Telophase
New nuclei form
Spindle fibers ____________
________________
form around each set of chromatids
Nucleoli ___________
End of nuclear division
disperse
Nuclear membranes
reform

22. Animal Cell Division in White Fish Blastula

23. Centrioles Centrioles Centromere Centrioles Chromatin _______________
Nuclear envelope
Centrioles
Chromatin
_______________
(paired chromatids)
Chromosomes
Daughter Cells
Spindle
Centrioles
Chromosomes
Individual
Nuclear envelope
reforms

24. Onion Root Tip

25. For Use with Lab:
Plant Cell Growth as seen in Onion Root Tip

26. New daughter cells form
Cytokinesis
Cytoplasmic division
New daughter cells form
In animal cells a _______________ 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 __________. A new _________ is laid down between the membranes, which fuses with the existing cell wall.
cleavage furrow
cell plate
cell wall

27. a. Division of the ________________ b. End of the ____ _________
V. Cytokinesis:
a. Division of the ________________
b. End of the ____ _________
c. Production of two ______________ daughter cells
d. Different in _________ and _________ cells
cytoplasm
cell
cycle
identical
plants
animals
Vesicles containing cell wall material
Cell plate forming
Cell plate
Daughter cells
Wall of parent cell
Daughter nucleus
Cell wall
New cell wall
Cleavage furrow
Contracting ring of microfilaments
Daughter cells

28. 10-3 Regulating the Cell Cycle Key Concepts: How is the cell cycle regulated? How are cancer cells different from other cells?
Multicellular
______________ organisms control cell growth and division very carefully (way to increase number of cells and size of organism)
replacement
This provides the _______________ of cells that ________________________.
wear out or are broken down

29. Controls on Cell Division:
Cells in a ________________ will continue to divide until they come into ___________ with other cells.
Then the cells ________ _____________.
Cells are ______________ from the center of the dish.
Then the cells _______________ the open space will begin dividing
until they have _______ the empty space.
The controls for cell growth and division can be ___________________.
We can see the same thing happen in our __________________.
petri dish
contact
stop
dividing
removed
bordering
filled
turned on and off
own bodies

30. Question: What happens when you cut your finger or break your bone? 1. 2. 4. 3. 5.
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.

31. II. Cell Cycle Regulators
1. Scientists wondered what ____________cell 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 ____________ regulates the cell cycle.
4. They rise and fall in time with the ________.
controlled
cyclins
cell cycle

32. 5. Cyclins _____________ the timing of the cell cycle in __________cells.
Two main groups of protein regulators:
1. Internal Regulators: respond to events __________________ .
Ex. Make sure cell doesn’t enter mitosis until chromosomes have all replicated
2. External Regulators: respond to events _________________________.
Ex. Embryonic growth and healing
regulate
eukaryotic
inside the cell
outside the cell

33. III. Uncontrolled Cell Growth
Cancer
Cell Growth is so controlled because when it is not controlled things go very, very______.
2. _________ is a disorder in which some of the body’s own cells lose the ability to control growth.
wrong
Cancer

34. 3. Cancer cells do not respond to the _____________that regulate the growth of most cells.
4. When cells divide ___________________ they form masses of cells called __________ that can damage the surrounding tissue.
5. Cancer cells can break off and _____________ throughout the body disrupting normal activities and causing serious medical problems or even death.
signals
uncontrollably
tumors
spread

35. B. Causes of Cancer
1. Smoking ____________
2. _____________ exposure
3. ______________
4.____________ defect
C. Cancer is a disease of the __________.
tobacco
Radiation
Viral Infection
Genetic
cell cycle

36. Breast Cancer Cell