bsecond lesson

2. Centrosome- area of the cytoplasm near the
nucleus that coordinates the building and
breaking of microtubules
Cytoplasm- gel-like substance of a cell
exclusive of the nucleus and plasma
membrane.
Endoplasmic reticulum-network of tubules
and vesicles in cytoplasm that contributes to
cellular protein manufactures.
Golgi Apparatus-organelle consisting of small
sacs stacked on one another near the pounds,
combines with protein molecules.
Lysosome- membranous organelle containing
Mitochondria-various enzymes that can
dissolve most cellular compounds.
Nucleus- membranous organelle that contains
most of the genetic cell material of the cell;
also, group of neuron cell bodies in the brain
or spinal cord.
Plasma Membrane-membrane that separates
the contents of the cell from the tissue
fluid, encloses the cytoplasm, and forms the
outer boundary of the cell.
Ribosome- organelle in the cytoplasm of cells
that synthesizes the proteins sometimes
called “protein factory”(1)(pg 69)

3. Inorganic compounds: chemical
constituents that do not contain both
carbon and hydrogen.
Water is the cradle of life.
Water is the body’s most abundant and
important compound. It makes up 70%
of body weight.
Properties of water: simple and stable
-strong polarity
-high specific heat
-vaporization
-cohesion
Oxygen and Carbon Dioxide important
in cellular respiration. Oxygen assists in
the decomposition reactions for the
release of energy from nutrients
burned in the cell. Carbon dioxide is
the exception to the definition that
“inorganic compounds do not contain
carbon”. Carbon is produced as a waste
product during cellular respiration to
help maintain the acid-base balance in
the body.
Electrolytes dissociate in a solution to
form ions.

4. Acids are any substances that release
hydrogen ions in a solution. “Proton
donor”
Bases have an increased number of
hydroxide ions. “Proton acceptor”
pH scale indicates whether a
substance is acidic or basic. When
hydrogen ions increase the pH goes
down and the substance becomes
acidic. When hydroxide ions increase
the pH goes up and the substance
becomes basic.
Buffers maintain the pH levels and
minimize change in concentrations of
hydrogen and hydroxide ions in the
body.
Salts are an inorganic compound that
results from a chemical reaction
between acids and bases.
(1)(page 44-47)
C-3

5. An organic compound always contains
carbon.
Many organic molecules consist of
subunits, called monomers, that are
joined together to form what are
referred to as polymers
Four major kinds of organic
molecules, Examples: carbohydrates,
lipids, proteins and nucleic acids
[C-6]

6. Cell Membrane
MLA Citation:
Davidson , Micheal. "plasma
membrane." Molecular Expressions.
optical Microscopy, 2004. Web. 15
Sep 2012.
<http://micro.magnet.fsu.edu/cells
/plasmamembrane/plasmamembrane
.html>.

7. The plasma (cell) membrane is the
boundary between the extracellular
fluid (fluid that is not contained
within the cells) and the intracellular
fluid (the fluid inside a cell).
Hydrophobic fatty acid tails face the
interior of the membrane because
they are a non-polar substance
meaning they don’t like water. The
hydrophilic polar heads face the
inside and outside of the membrane
because they are polar substances
meaning they are attracted to water.
There are two types of proteins,
integral (trans membrane) and
peripheral proteins. Integral proteins
pass through the entire membrane
and peripheral proteins only stay near
the intracellular face of the
membrane. Some of the time there
are Carbohydrate chains attached to
the phospholipids and integral
proteins which form glycolipids and
glycoproteins.

10. Roles played by Proteins in the Cell
Membrane:
1. Act as channels or active
transport molecules to selectively
transport of substances across the
phospholipid bilayer
2. Function as receptors and provide
information for molecules, such
as hormones, communicate by
sending signals of the information
obtained to the interior of the
cell.
3. Show enzymes catalyze reactions
related to the plasma membrane.
4. There are also proteins which pull
membrane proteins to cause cell
movement, called motor
molecules. (They are usually
peripheral proteins.)
5. 5. Glycoproteins identify cells.
6. Cell adhesion molecules (CAMs)
bind one cell to another.
1. 7. There are also carrier proteins
which are integral proteins that
bind to specific molecules and
transport them to the other side
of the membrane

11. Note: The picture above shows the
second messenger system
Messenger proteins are also important
in activating the second messenger
system.
The steps to this process is below

12. 1. A messenger, such as a hormone,
binds to a receptor site.
2. The receptor then releases a G
protein.
3. G protein may bind to a
membrane-bound enzyme.
4. Enzyme then converts to ATP to
cyclic AMP or cAMP (the second
messenger)
5. cAMP activates kinase, an enzyme
that adds phosphate groups to
other cytosolic enzymes.
6. As a result, it activates some and
deactivates others leading to an
alteration in various metabolic
activities.