• http://www.sirinet.net/~jgjohnso/aphome.html
• This is a GREAT website made by another AP
Biology teacher in Oklahoma. Check it out.
There are practice quizzes, notes etc etc.
• Review your metric measurements:
SEE PAGE 103
• n = 10-9 m
• µ = 10-6 m
• mm = 10-3 m
• cm = 10-2 m
Closed system
Open system
Using energy
gradients
(energy at each
step) to help do
work. Staying
away from
equilibrium.
(like
respiration!)
how is a human
an open system?
Negative G
= a loss of free
Energy
The products have less energy than the
reactants, EXERGONIC
Figure 7.3
cell fractionation, centrifuge
What are the largest organelles/parts of a cell that
fraction off into the pellet first? What are the smallest? (last)
(What are microsomes?)
The endomembrane system’s interconnectedness.
All membranes are the same bilayer.
Peroxisomes
• Consume deadly free oxygen within the
cell, transport it to mitochondria.
• Enzymes transfer hydrogen to oxygen,
producing hydrogen peroxide (H2O2)
• H2O2 is also toxic to a cell, and an enzyme
made by the peroxisome can break down
H2O2 into O and H2O when necessary.
• Fig. 7.19
The cytoskeleton maintains the
cell’s shape and more… p.120
Microtubules
largest
compression resisting (girders)
made of tubulin (tube)
large scale movements:
chromosomes
flagella, cilia,
Microfilaments
smallest
tension bearing (resists pulling)
made of actin
muscle contraction
cytoplasmic movements (see 7.27)
Intermediate filaments
intermediate size 
tension bearing (resists pulling)
made of keratin-type proteins
anchors organelles
Microfilaments and
movement
•
http://www.accessexcellence.org/RC/VL/GG/images/Fig_16.36.jpg
http://ccollege.hccs.cc.tx.us/instru/Biology/AllStud
yPages/Cells/Plant_Animal.htm
http://homepage.ntlworld.com/postalmicsoc/spagfr1.jpg
Amphipathic nature of the phospholipid bilayer
What can diffuse through the hydrophobic zone of the bilayer
and what cannot?
How can molecules get into a cell if they are not able to diffuse
through the membrane directly?
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/bilayer.gif
The endomembrane
system
Why are there
so many
different
organelles
and so many
different
membranes
inside a cell?
Answer: Gives the cell the ability to do many different specialized
reactions at one time, in different parts of the cell—complexity!
Animal cells and osmosis
http://www.sirinet.net/~jgjohnso/table5-1.jpg
• Paramecium
• Contractile
vacuole
http://www.sirinet.net/~jgjohnso/homeostasis.html
• In your book, page 145
questions
6-10 practice
The Cell =
0.03M sucrose
0.02M glucose
Environment =
0.01M sucrose
0.01M glucose
0.01M fructose
The membrane is permeable to
everything but sucrose.
• Unless cited, most slides/pictures were
taken from the Campbell Reece Mitchell
textbook, BIOLOGY, 2000. Instructor CDRom