Transcript Chapt 9 notes - Kasson-Mantorville High School

Chapter 9 Cellular Reproduction
Section 1: Cellular Growth
Section 2: Mitosis and Cytokinesis
Section 3: Cell Cycle Regulation
Click on a lesson name to select.
Q: Why are cells limited to being small in size?
(use SA/Vol ratio in answer)
Click on a lesson name to select.
Chapter 9
Cellular Reproduction
9.1 Cellular Growth
Ratio of Surface Area to Volume
Chapter 9
Cellular Reproduction
9.1 Cellular Growth
Transport of Substances
 Substances move by diffusion or by
motor proteins.
 Diffusion over large distances is slow
and inefficient.
 Small cells maintain more efficient
transport systems.
Chapter 9
Cellular Reproduction
9.1 Cellular Growth
 Why are cells limited to being small in
size?
 As the cell grows, its volume increases
much more rapidly than the surface
area.
 The cell might have difficulty supplying
nutrients and expelling enough waste
products.
Chapter 9
Cellular Reproduction
9.1 Cellular Growth
The Cell Cycle
 Cell division prevents the cell from becoming
too large.
 It also is the way the cell reproduces so that
you grow and heal certain injuries.
 Cells reproduce by a cycle of growing and
dividing called the cell cycle.
Q: Draw the cell cycle, putting steps in correct
order, and explain briefly what happens in each
stage / substage:
Chapter 9
Cellular Reproduction
9.1 Cellular Growth
 I. Interphase is the stage during which the
cell grows, carries out cellular functions,
and replicates. (G1, S, G2)
 II. M Phase
 Mitosis is the stage of the cell cycle during
which the cell’s nucleus and nuclear
material divide. (ProMAT)
 Cytokinesis is the method by which a cell’s
cytoplasm divides, creating a new cell.
Cell Cycle
Interphase:
a. G1: Growth 1, cells make organelles, make more cytoplasm,
cell “does its thing”
b. S: Synthesis phase, Cell makes copy of DNA in anticipation of
mitosis
c. G2: Growth 2, cells make proteins and organelles needed for
mitosis and cytokinesis
M Phase
Mitosis: Duplicated DNA is divided. One set goes to each side.
“ProMAT”
Cytokinesis: Cell divides in two
Chapter 9
Cellular Reproduction
9.1 Cellular Growth
Product Assignment: Cell cycle Concept Map
Make a Inspiration concept map of the Cell Cycle
Things to include: Interphase phases (G1, S, G2).
M Phase sub-phases (stages of mitosis and
Cytokinesis).
A work: Image icons (not just plain boxes) used
>85% of terms
All connectors have a linking phrase on the line
(causes, opposes, includes, etc)
for
Q: Describe how DNA is packaged into a
chromosome
Chromosomes
-DNA is stored in structures called
Chromosomes
-Condensed chromosomes only form when the
cell is dividing
Normally DNA
is in a looser
form called
CHROMATIN
Q: What is the difference between haploid
and diploid? Use a sketch (or two) in your
answer.
Haploid vs. Diploid
Some organisms (species) are diploid
-This means they have two copies of
each unique (or different chromosome)
Ex. Humans:
46 total chromosomes
23 unique or different chromosomes
(one comes from each parent)
We have 46 total
chromosomes
We have 23 unique
chromosomes
On each pair of
chromosomes are
genes for the same
traits in the same order
Mom’s
Chrom. #1
Dad’s
Chrom. #1
Gene for hair color
Gene for hair color
Mom’s codes for red
Dad’s codes for brown
Haploid vs. Diploid
Some organisms (species) are haploid
-This means they have only 1 copy of
each unique (or different)
chromosome
ex. Fungi are haploid
They only have one copy of each
chromosome and must reproduce
through different means than do most
organisms
The term “chromosome” is ambiguous
-Meanings:
A. How many unique chromosomes
an organism has (chrom # =?)
B. One unreplicated chromosome
(half of “X” AKA chromatid)
C. One replicated chromosome
(“X”)
Ambig. Chromosome meaning A.
-Each species has a characteristic chromosome #...”How
many chromosomes does the creature have?”
Humans have a chrom # of 46
(46 total)
2n=46 n=23
Camels have 70
King crab has 208
Mosquito has 6
Honest Abe should have
more chromosomes than
a crab!
I don’t care if it is giant!
Q: Draw a diploid set of chromosomes in an
unreplicated state:
Ambig. Chromosome meaning B.
-Unreplicated chromosomes
Chrom. 3 from
Mom
Chrom 3
from Dad
This is how chromosome would be in
G1 Interphase
Q: Draw a diploid set of chromosomes in a
replicated state:
Ambig. Chromosome meaning C.
-Replicated chromosomes
Chrom. #5
from Mom
Chrom. #5
from Dad
Two copies of mom’s and
dad’ because cell is
getting ready for mitosis
This is one replicated Chrom.
from either mom or dad
Each half of mom’s “X”
(and dad’s) is called a
chromatid
Mistake students make: One
half of above is from mom, the
other half from dad **Not true**
Replicated chromosomes
This is state chromosomes are in from S phase
through mid Mitosis (until chromatids are
pulled apart to be delivered to new cells that
form
DNA as chromatin
DNA goes from chromatin to chromosomes during Prophase
Q Explain the purpose (“what’s the point?”)
of Mitosis:
Chapter 9
Cellular Reproduction
9.2 Mitosis and Cytokinesis
The Stages of Mitosis
 Prophase
 The cell’s chromatin tightens into
densely packed chromosomes.
 Sister chromatids are attached at the
centromere.
 Spindle fibers form in the cytoplasm.
Chapter 9
Cellular Reproduction
9.2 Mitosis and Cytokinesis
 The nuclear
envelope seems
to disappear.
 Spindle fibers
attach to the sister
chromatids.
Q List the stages of mitosis in order and
then briefly describe what happens in each:
Mitosis = “ProMAT”
Stage 1: Prophase
Lumpy
Chromosomes
become visible
Chromosomes go
from chromatin
to chromosomes
in this phase
Chapter 9
Cellular Reproduction
9.2 Mitosis and Cytokinesis
Metaphase
 Sister chromatids
are pulled along the
spindle apparatus
toward the center of
the cell.
 They line up in the
middle of the cell.
Mitosis = “ProMAT”
Stage 2: Metaphase
Chromosomes line up at cell
“equator”waiting to be pulled
apart to 2 new cells
Chapter 9
Cellular Reproduction
9.2 Mitosis and Cytokinesis
Anaphase
 The microtubules of the spindle apparatus
begin to shorten.
 The sister chromatids separate.
 The chromosomes move toward the poles
of the cell.
Mitosis =
“ProMAT”
Stage 3: Anaphase
Chromosomes are being
pulled a part / “reeled in” by
the 2 ends of the new cells
Chapter 9
Cellular Reproduction
9.2 Mitosis and Cytokinesis
Telophase
 The chromosomes arrive at the poles and
begin to relax. (i.e. DNA into Chromatin
form
 Nucleus reforms at each end of cell
 The spindle apparatus disassembles.
Mitosis = “ProMAT”
Stage 4: Telophase
Chromosomes are separated to 2
ends of new cells
Cytokinesis usually begins now
Pro
Ana
Met
Telo
1 interphase
3 early prophase
4 mid prophase
5 late prophase
7 early anaphase
8 anaphase
9 early telophase
2 interphase / beginn
ing prophase
6 metaphase
10 telophase
Chapter 9
Cellular Reproduction
9.2 Mitosis and Cytokinesis
Cytokinesis
 In animal cells, microfilaments constrict, or
pinch, the cytoplasm.
 In plant cells, a new structure, called a cell
plate, forms.
Cytokinesis:
-Cell physically splits into 2 new cells now that DNA is divided
-Cytoskeleton proteins tighten like belt to pinch cell in two
Onion cell mitosis lab
Q Define what apoptosis is and describe the
3main scenarios in which it would happen in
your body:
Chapter 9
Cellular Reproduction
Apoptosis = Programmed cell death
(AKA “cell suicide”)
 Cells going through apoptosis actually shrink,
shrivel, and die in a controlled process.
 Apoptosis is used for:
 Cells infected with viruses kill self to
protect other cells
 Mutated cells kill self before they can
become cancerous
 Embryologic cells that aren’t in adult (web
fingers)
• Cancerous cells show Loss of apoptosis:
– When normal cell suffers high DNA damage or
gets infected by a virus it kills itself. Cancer
cells lose this protective feature.
– (peeling sunburn = cells that had DNA damage
and killed themselves so as not to become
cancerous)
Chapter 9
Cellular Reproduction
9.3 Cell Cycle Regulation
Quality Control Checkpoints
 The cell cycle has built-in checkpoints that
monitor the cycle and can stop it if something
goes wrong.
 Spindle checkpoints also have been identified
in mitosis.
Main checkpoint
Matching
10_____Cancerous
11_____Benign
12_____Malignant
13_____Metastisis
14_____Carcinogens E
A.
B.
C.
D.
cells divide too much but can’t invade other tissues
A cancer causing substance or agent (tobacco smoke, radiation
malignant cells break away and travel through blood to other area
cell that is in uncontrolled / continuous mitosis and cytokinesis
Chapter 9
Cellular Reproduction
9.3 Cell Cycle Regulation
Carcinogen
Warning
Causes of Cancer
 The changes that occur in the
regulation of cell growth and division
of cancer cells are due to mutations.
(caused by carcinogens)
 Various environmental factors can affect the
occurrence of cancer cells.
 Radiation (ex. UV Light!!)
 Tobacco smoke
 Human papilloma virus (HPV)
Chapter 9
Cellular Reproduction
9.3 Cell Cycle Regulation
Abnormal Cell Cycle: Cancer
 Cancer is the
uncontrolled growth
and division of cells.
How does cancer hurt people?
• Cancer kills by “getting in the way” not
through toxins or “attacking” other cells
 Cancer cells can kill an
organism by crowding
out normal cells,
resulting in the loss of
that tissue’s function.
Terminology
• Cancerous: cell that is in uncontrolled / continuous mitosis and
cytokinesis
• Benign tumor: cells divide too much but can’t invade other
tissues
• Malignant tumor: cells growing abnormally and can invade
nearby tissue
• Metastasis: Malignant cells break away and travel through
blood to other area
• Carcinogens:
smoke, radiation.
A cancer causing substance or agent (tobacco
Describe (list) the kinds of things scientists
think need to happen in order to turn a
regular cell into the worst type of cancer cell:
Origin of Cancer cells
• Several mutations (~7-8) are thought to
be needed to turn a cell cancerous
– Two key types of genes that if mutated could cause
cell to become cancerous:
– A. Tumor Suppressor gene: gene that
results in a protein that stops cell division
– B. Proto-Oncogene: gene that results in
a protein that starts cell division
• Normal cells show Contact inhibition of cell
division.
– Cultured cells normally
divide until they form a
single layer on the inner
surface of the culture
container.
– If a gap is created, the
cells will grow to fill
the gap.
• Most animal cells also exhibit anchorage
dependence for cell division.
– To divide they must be anchored to a substratum,
typically the extracellular matrix of a tissue.
• Cancer cells are free of both densitydependent inhibition and anchorage
dependence.
Q Explain the difference between benign
cancer cells and malignant cancer cells
Progression form normal cell to
cancerous cell
To become (worst) Cancerous:
• 1. Lose tumor suppressor gene (loose
brakes)
• 2. Turn a proto-oncogene into an an
oncogene (apply gas)
• 3. Lose Contact inhibition (grow into clump)
• 4. Lose Anchorage dependance
(metastasize)
• 5. Lose Apoptosis gene (don’t kill selves)
• How many years of smoking does it take for all of these to occur in one
cell?
• How many of these mutations happen during each week of tanning
sessions?
Q Why do cancers become more common
as people get older?
Cancer Treatment
• Surgery: Physically remove cancerous cells
• Radiation therapy: Shoot radiation at cancer cells
– Radiation destroys cells
– Accurate targeting allows radiation to be concentrated on tumor
• Chemo therapy: Drugs that kill all dividing cells are taken
– Most good body cells are not normally dividing so mostly Ca cells killed
– Some body cells are dividing (hair, intestinal wall, immume) so they will be
damaged
– Must give a dose to kill many Ca cells, but then back off so normal cells
that got damaged can regrow
– Repeat dose/recovery until Ca cells gone
– Some cancers grow too fast and you can’t give chemo fast enough to kill
them (person would die from lack of intestinal cells before all Ca cells were
wiped out)
Ca product:
Describe the steps that are required to turn a
normal cell from some area in body (skin,
intestine, lung, etc) into the worst type of
metastatic cancer cell….
through a “picture story”
Q Why are scientists working on stem cells?
Chapter 9
Cellular Reproduction
9.3 Cell Cycle Regulation
Stem Cells
 Unspecialized cells
that can develop into
specialized cells
when under the right
conditions
Q Define each and indicate which type of
stem cells (embryonic or adult) each term
applies to:
A. Pluripotent
B. Multipotent
Chapter 9
Cellular Reproduction
9.3 Cell Cycle Regulation
Embryonic Stem Cells
 After fertilization, the resulting mass of cells
divides repeatedly until there are about
100–150 cells. These cells have not become
specialized.
“murder” or potentially life svaing
research?...all in the eye of the
beholder
Embryonic Stem cells exhibit Pluripotency
(unlimited potential = can become any cell type)
Q Why is the use of embryonic stem cells
more controversial than the use of adult?
Chapter 9
Cellular Reproduction
9.3 Cell Cycle Regulation
Adult Stem Cells
 Found in various tissues in the body and
might be used to maintain and repair the
same kind of tissue
 Less controversial because the adult stem
cells can be obtained with the consent of
their donor
Adult stem cells exhibit Multipotency
(limited potential = can become one of a limited
set of cell types)
Q Why do most research scientists have
more interest in working with embryonic
stem
Q Create a Venn diagram that compares
embryonic stem cells and adult stem cells:
Chapter 9
Cellular Reproduction
Chapter Resource Menu
Chapter Diagnostic Questions
Formative Test Questions
Chapter Assessment Questions
Standardized Test Practice
biologygmh.com
Glencoe Biology Transparencies
Image Bank
Vocabulary
Animation
Click on a hyperlink to view the corresponding lesson.
Chapter 9
Cellular Reproduction
Chapter Diagnostic
Questions
Which is the first phase of mitosis?
A. interphase
B. prophase
C. metaphase
D. telophase
Chapter 9
Cellular Reproduction
Chapter Diagnostic
Questions
During what phase do the sister chromatids
line up in the middle of the cell?
A. interphase
B. metaphase
C. anaphase
D. telophase
Chapter 9
Cellular Reproduction
Chapter Diagnostic
Questions
Which is not a phase of the cell cycle?
A. cytokinesis
B. interphase
C. apoptosis
D. mitosis
Chapter 9
Cellular Reproduction
9.1 Formative
Questions
Which can more efficiently supply nutrients and
expel waste products?
A. larger cells
B. smaller cells
C. cells with lower surface area to volume ratio
D. cells shaped like a cube
Chapter 9
Cellular Reproduction
9.1 Formative
Questions
At what stage does a cell spend most of
its life?
A. cytokinesis
B. interphase
C. mitosis
D. synthesis
Chapter 9
Cellular Reproduction
9.1 Formative
Questions
What happens in the cell during cytokinesis?
A. The cell grows and carries out normal
functions.
B. The cell copies its DNA and forms
chromosomes.
C. The cell’s nucleus and nuclear material
divide.
D. The cell’s cytoplasm divides.
Chapter 9
Cellular Reproduction
9.2 Formative
Questions
In what stage of the cell cycle does the
cell’s replicated genetic material separate?
A. cytokinesis
B. interphase
C. mitosis
D. prophase
Chapter 9
Cellular Reproduction
9.2 Formative
Questions
Which diagram shows anaphase?
A.
B.
C.
D.
Chapter 9
Cellular Reproduction
9.2 Formative
Questions
True or False
At the end of mitosis the nuclear material is
divided and two new cells have formed.
Chapter 9
Cellular Reproduction
9.3 Formative
Questions
What are the “key and ignition” that start the
various activities in the cell cycle?
A. chromatin and chromosomes
B. cyclin and CDKs
C. microtubules and spindle fibers
D. protein and ribosomes
Chapter 9
Cellular Reproduction
9.3 Formative
Questions
Which of these cancer-causing substances or
agents is impossible to avoid completely?
A. chemicals such as asbestos
B. food and drinks that the FDA warns may
contain carcinogens
C. tobacco and second-hand smoke
D. ultraviolet radiation from the Sun
Chapter 9
Cellular Reproduction
9.3 Formative
Questions
What is the term for the programmed death
of cells that are damaged beyond repair or
have harmful changes in their DNA?
A. apoptosis
B. carcinogens
C. cytokinesis
D. mitosis
Chapter 9
Cellular Reproduction
9.3 Formative
Questions
Which cells are not locked into becoming
one particular kind of cell and are capable
of developing into specialized tissues?
A. apoptotic cells
B. cancer cells
C. prokaryotic cells
D. stem cells
Chapter 9
Cellular Reproduction
Chapter Assessment
Questions
This cell has completed what stage of
mitosis?
A. anaphase
B. interphase
C. metaphase
D. telophase
Chapter 9
Cellular Reproduction
Chapter Assessment
Questions
What term is used to describe programmed
cell death?
A. apoptosis
B. anaphase
C. necrosis
D. cyclins
Chapter 9
Cellular Reproduction
Chapter Assessment
Questions
What is the role of cyclins in a cell?
A. to control the movement of microtubules
B. to signal for the cell to divide
C. to stimulate the breakdown of the
nuclear membrane
D. to cause the nucleolus to disappear
Chapter 9
Cellular Reproduction
Standardized Test
Practice
Which cell has the lowest ratio of surface area
to volume?
B
A
C
Chapter 9
Cellular Reproduction
Standardized Test
Practice
At what stage of interphase does the cell take
inventory and make sure it is ready for the division
of its nucleus?
A. G1
B. S
C. G2
D. M
Chapter 9
Cellular Reproduction
Standardized Test
Practice
Which occurs in plant cells but not animal cells
during the cell cycle?
A. formation of a cell plate
B. formation of microtubules
C. formation of a cleavage furrow at the equator
of the cell
D. movement of chromosomes to the poles of
the cell
Chapter 9
Cellular Reproduction
Standardized Test
Practice
True or False
Multiple changes in DNA are required to
change an abnormal cell into a cancer cell.
Chapter 9
Cellular Reproduction
Standardized Test
Practice
Which is not a condition that can result in cancer?
A. a failure in the control mechanisms that
regulate the cell cycle
B. a failure in the repair systems that fix
changes or damage to DNA
C. a failure of the spindle fibers to move
chromosomes during mitosis
D. mutations or changes in segments of DNA
that control protein production
Chapter 9
Cellular Reproduction
Glencoe Biology Transparencies
Chapter 9
Cellular Reproduction
Image Bank
Chapter 9
Cellular Reproduction
Vocabulary
Section 1
cell cycle
interphase
mitosis
cytokinesis
chromosome
chromatin
Chapter 9
Cellular Reproduction
Vocabulary
Section 2
prophase
sister chromatid
centromere
spindle apparatus
metaphase
anaphase
telophase
Chapter 9
Cellular Reproduction
Vocabulary
Section 3
cyclin
cyclin-dependent kinase
cancer
carcinogen
apoptosis
stem cell
Chapter 9
Cellular Reproduction
Animation
 Visualizing the Cell Cycle