CHROMOSOMES

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Materials move through cells by diffusion.
Oxygen and food move into cells, while waste
products move out of cells. How does the size of
a cell affect how efficiently materials get to
all parts of a cell? Work with a partner to
complete this activity 1. On a sheet of paper,
make a drawing of a cell that has the following
dimensions 5 cm x 5 cm x 5 cm. Your partner
should draw another cell about one half the size
of your cell on a separate sheet of paper. 2.
Compare your drawings. How much longer do you
think it would taketo get from the cell membrane
to the center of the big cell than from the
cell membrane to the center of the smaller
cell? 3.What is the advantage of cells being
small?
It would take twice the amount of time.
If cells are small, materials can be distributed
to all parts of the cell quickly.
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Image by Riedell
Image from http//www.bcps.org/offices/lis/model
s/life/images/grow.JPG
CELL GROWTH DIVISION 10-1 10-2

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2 Reasons why cells divide
DNA OVERLOAD

• 1. _____________________As cell grows bigger
  demand on DNAgenetic library becomes too great

Ex Small town library has 1000 books. As town
grows and more people borrow books, there may be
a waiting list to read the most popular titles
http//www.adc.state.az.us/images/Off-Library.JPG
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2 Reasons why cells divide
Material exchange cant keep up

• 2. _____________________As cell grows bigger
  demand for transport across membrane is too great

http//www.animationlibrary.com
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Ability to transport of oxygen, food, waste
across cell membrane depends on
_______________ Need for these depends on
___________
SURFACE AREA
CELL VOLUME
As cell grows these DONT increase at the same
rate
See relationshipbetween volume and SA
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Ratio of Surface Area to Volume in Cells
Section 10-1
Cell Size
Surface Area (length x width x 6)
Volume (length x width x height)
Ratio of Surface Area to Volume
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• BIGGER CELLS NEED MORE FOOD
• and OXYGEN, but CANT TRANSPORT
• IT FAST ENOUGH or IN BIG
• ENOUGH QUANTITIES!

http//www.animationlibrary.com
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Image by Riedell
Image from http//www.bcps.org/offices/lis/model
s/life/images/grow.JPG
Multicellular organisms grow mainly by
increasing cell number
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DNA CAN BE
SPREAD OUT INNON-DIVIDING CELLS
SCRUNCHED UP IN DIVIDINGCELLS
CHROMATIN
CHROMOSOMES
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DNA in PROKARYOTES

• BACTERIAL DNA is CIRCULAR
• HAVE ONE CHROMOSOME
• NO NUCLEUS ATTACHED TO CELL MEMBRANE

http//www.origin-life.gr.jp/3202/3202121/fig6.jpg
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DNA in EUKARYOTES(Plants Animals)

• DNA is ROD-SHAPED CHROMOSOMES
• MANY PAIRS
• FOUND IN NUCLEUS

http//cellbio.utmb.edu/cellbio/chrom2.jpg
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Chromosome structure
CHROMATIDS

• ___________________ 2 identical arms
• __________________
• constricted area holds chromatids
  together

CENTROMERE
HOMOLOGOUS

• __________________ PAIR
• 2 of each chromosome(one from mom one from
  dad)

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HOMOLOGOUS CHROMOSOMES

• SAME SIZE
• SAME SHAPE
• CARRY GENES for the SAME TRAITS
• BUT ______________!
• (Dont have to have the SAME CHOICES)

NOT IDENTICAL
http//arnica.csustan.edu/biol3020/cell_division/c
ell_division.htm
http//sps.k12.ar.us/massengale/genetics20tutoria
l.htm
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CELL DIVISION in PROKARYOTES

• Bacteria reproduce using
• __________________________________

BINARY FISSION
http//fig.cox.miami.edu/cmallery/150/mitosis/fis
sion.jpg
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______________ series of events that cells go
through as they grow and develop
CELL CYCLE
cells alive cell cycle
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CELL CYCLE

• INTERPHASE non-dividing phase
• G1- Grow bigger Cell is doing its
  job DNA is spread out as chromatin
• S - Synthesis (copy DNA) chromosomal
  proteins
• G2- Grow bigger, make organelles
  molecules needed for cell division

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CELL DIVISION

• MITOSIS Nuclear division
• Prophase
• Metaphase
• Anaphase
• Telophase
• Cytokinesis Cytoplasm divides
• G0 cell stops dividing (Ex nerve cell)

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Figure 104 The Cell Cycle
Section 10-2
G1 phase
M phase
S phase
G2 phase
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(No Transcript)
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• INTERPHASE (G1 - S - G2)

In between divisionsCells are in this phase most
of the time Can see nucleus DNA spread out as
chromatin
Cant see chromosomes
DNA gets copied (S) Cell gets ready to
divide
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Pearson Education Inc publishing as Pearson
Prentice Hall

• PROPHASE
• 1st dividing phase

http//www.life.uiuc.edu/plantbio/102/lectures/08m
itveg102.html
DNA scrunches into chromosomes
Centrioles appear in centrosome region
move to poles
Nuclear membrane nucleolus disappear
Spindle fibers form attach to
chromosomes
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________ region organizes spindle
CENTROSOME

• Spindle MICROTUBULES are part of cytoskeleton

http//www.coleharbourhigh.ednet.ns.ca/library/org
anelle_worksheet.htm
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• METAPHASE

Chromosomes line up in ___________
middle
Images fromPearson Eduction Ince Publishing as
Pearson Prentice Hall http//www.science.siu.edu/
plant-biology/PLB117/JPEGs20CD/0247.JPG
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• ANAPHASE

Centromeres splitCentrioles pull
chromatids_______
apart
Images fromPearson Eduction Ince Publishing as
Pearson Prentice Hall http//www.science.siu.edu/
plant-biology/PLB117/JPEGs20CD/0247.JPG
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• TELOPHASE (reverse prophase steps)

two
See ______ nuclei
Nuclear membrane nucleolus return
Chromosomes spread out as chromatin
Centrioles disappear
Spindle fibers disappear
Images fromPearson Eduction Ince Publishing as
Pearson Prentice Hall http//www2.bc.cc.ca.us/cnew
ton/Biology2011/Mitosis.html
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CYTOKINESIS Cytoplasm splits into 2 cells

ANIMAL CELLS pinch cytoplasm in two with a
______________________
CLEAVAGE FURROW
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CYTOKINESIS Cytoplasm splits into 2 cells

PLANT CELLS cant pinch because they have a
sturdy ____________ Plant cells separate
cytoplasm by growing a _______________ down the
middle.
CELL WALL
CELL PLATE
http//www.eastcentral.edu/acad/depts/BI/plant_mit
osis_nolabels.html
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Figure 105 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Centromere
Chromatin
Centriole
Nuclear envelope
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Individual chromosomes
Telophase
Anaphase
Nuclear envelope reforming
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Figure 105 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Centromere
Chromatin
Centriole
Nuclear envelope
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Individual chromosomes
Telophase
Anaphase
Nuclear envelope reforming
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Figure 105 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Centromere
Chromatin
Centriole
Nuclear envelope
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Individual chromosomes
Telophase
Anaphase
Nuclear envelope reforming
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Figure 105 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Centromere
Chromatin
Centriole
Nuclear envelope
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Individual chromosomes
Telophase
Anaphase
Nuclear envelope reforming
32
Figure 105 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Centromere
Chromatin
Centriole
Nuclear envelope
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Individual chromosomes
Telophase
Anaphase
Nuclear envelope reforming
33
Figure 105 Mitosis and Cytokinesis
Section 10-2
Spindle forming
Centrioles
Centromere
Chromatin
Centriole
Nuclear envelope
Chromosomes (paired chromatids)
Interphase
Prophase
Spindle
Cytokinesis
Centriole
Metaphase
Individual chromosomes
Telophase
Anaphase
Nuclear envelope reforming
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Videos

Animal Cell Mitosis
Animal Cell Cytokinesis
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Concept Map
Section 10-2
Cell Cycle
includes
is divided into
is divided into
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Concept Map
Section 10-2
Cell Cycle
includes
is divided into
is divided into
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SOUTH DAKOTA CORE SCIENCE STANDARDS
LIFE SCIENCEIndicator 1 Understand the
fundamental structures, functions,
classifications, and mechanisms found in living
things

• 9-12.L.1.1. Students are able to relate cellular
  functions and processes to specialized structures
  within cells.
• Transport (ANALYSIS)
• cell membranes, homeostasis
• Cell life cycles (ANALYSIS)
• Examples somatic cells (mitosis)

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Core High School Life SciencePerformance
Descriptors
High school students performing at the ADVANCED level predict the function of a given structure predict the outcome of changes in the cell cycle predict how homeostasis is maintained within living systems
High school students performing at the PROFICIENT level describe the relationship between structure and function explain how homeostasis is maintained within living systems compare and contrast the cell cycles in somatic and germ cells
High school students performing at the BASIC level recognize that different structures perform different functions define homeostasis describe the life cycle of somatic cells