What is Surface Area? How is the surface area represented in a
cell?
Slide 5
What is Volume? What happens when the volume of a cell
increases?
Slide 6
Mini-Lab 9.1 Investigate Cell Size CellCell SizeCell Surface
Area (L x W x 6) Cell Volume (L x W x H) Cell 10.00002 m Cell
20.001 m Cell 32.5 cm (0.025 m) Cell 430 cm (0.3 m) Cell 515 m
Slide 7
CellCell SizeCell Surface Area (L x W x 6) Cell Volume (L x W x
H) SA : V Cell 10.00002 m0.00000000240.000000000000008300, 000 : 1
Cell 20.001 m0.0000060.0000000016000 : 1 Cell 32.5 cm (0.025 m)
0.003750.000015625240 : 1 Cell 430 cm (0.30 m) 0.540.02720 : 1 Cell
515 m135033751 : 2.5
Slide 8
Limits to Cell Size Smaller cells can better: 1. exchange
nutrients and expel wastes across the plasma membrane. higher
surface area to volume ratio (SA:V) 2. transport substances within
the cell. diffusion motor proteins 3. communicate instructions for
cellular functions. signal proteins
Slide 9
Cell Cycle Events of the Cell Cycle
Slide 10
Cell Division When a cell reaches its maximum size, the nucleus
initiates cell division. Cell division the splitting of a single
cell into two cells. Big Bang by M. Ormestad 2006 All rights
reserved
Slide 11
Cell Division Cells divide so that an organism can grow.
increases mass of organism changes organism - differentiation can
repair damaged cells and tissues. regeneration maintenance can
reproduce.
Slide 12
The Cell Cycle process of growing and dividing repeated
continuously creates two cells from one cell normal animal cells -
takes 12-24 hours 3 main stages interphase mitosis cytokinesis
Slide 13
Interphase period of time during which the cell grows, carries
out cellular functions, and makes copies of its DNA in preparation
for cell division 3 parts (substages) G1 gap 1 S synthesis G2 gap
2
Slide 14
Chapter 9.2 Mitosis and Cytokinesis
Slide 15
Mitosis & Cytokinesis Mitosis the cells nuclear material
divides 4 parts (substages) Cytokinesis the cell cytoplasm is
divided into two daughter cells
Slide 16
Chromosomes structures that contain the genetic material of an
organism only visible during mitosis formed when chromatin is wound
tightly around proteins called histones
Slide 17
Why Chromosomes? Cell must insure that each new daughter cell
gets a complete copy of the cells DNA. Accomplished by: 1.
Duplicating each chromosome during the S-phase of the cell cycle.
2. Holding these two copies (sister chromatids) together by a ring
of proteins called cohesins. 3. Condensing the chromosomes into a
compact form. 4. Separating the sister chromatids and 5.
Distributing these equally between the two daughter cells. Inage
courtesy of J. R. Paulson and U. C. Laemmli
Slide 18
Chromosome Structure sister chromatids identical copies copies
created during synthesis of interphase attached at beginning of
mitosis centromere Structure where the sister chromatids are
attached telomeres associated with programmed cell death
Slide 19
Stages of Mitosis Prophase Metaphase Anaphase Telophase Human
cell undergoing cytokinesis from M. Pines, Inside the Cell: The New
Frontier of Medical Science. U.S. Dept. of Health, Education, and
Welfare, 1978.
Slide 20
Prophase 1 st stage longest Chromosomes condense Spindle
apparatus forms mitotic spindle centrosome centrioles Nuclear
membrane disintegrates Nucleolus disappears Chromosomes attach to
spindle apparatus
Slide 21
Metaphase 2 nd stage shortest sister chromatids pulled by motor
proteins along the spindle apparatus toward the center of the cell
line up along the middle, or equator
Slide 22
Anaphase 3 rd stage sister chromatids are pulled apart spindle
apparatus microtubules shorten separates chromatids into two
identical sets
Slide 23
Telophase 4 th & last stage opposite of prophase
Chromosomes arrive at poles of spindle apparatus decondense Nuclear
membrane and nucleolus reform Spindle apparatus is broken down or
recycled May occur simultaneously with cytokinesis
Slide 24
Another Look at Mitosis
Slide 25
Cytokinesis division of the cytoplasm into two daughter cells
Animal cells microfilaments constrict cell membrane pinches cell in
two cleavage furrow Plant cells construct a cell plate new cell
wall forms on either side of cell plate Prokaryotic cells DNA
copies attach to plasma membrane plasma membrane grows and pulls
DNA copies apart cell membrane pinches into two cells
Slide 26
Mitosis in Motion http://www.johnkyrk.com/mitosis.html
http://www.cellsalive.com/mitosis.htm
http://www.sci.sdsu.edu/multimedia/mitosis/navigator.html
http://www.sumanasinc.com/webcontent/animations/content/
mitosis.html
http://www.sumanasinc.com/webcontent/animations/content/
mitosis.html