NAME______________________________________________ DATE____________ PERIOD____________
3.3 TEKS 3E, 4B, 9A Cell Membrane & Functions Using a Biology Book
Pg 81- The cell membrane or _______________ membrane, forms a boundary between a cell and the
______________ environment. The cell membrane consists of a _______________ layer of
phospholipids interspersed with a variety of other molecules. A ________________ is a molecule
composed of three basic parts, a charged _____________ group, glycerol, and two ___________ acid
chains. Together, the glycerol and the phosphate group form the _________ of a phospholipid; the
fatty acids form the ______________. The polar heads forms hydrogen bonds with _________
molecules and the fatty acid tails are nonpolar and __________ form hydrogen bonds with water. As a
result, the nonpolar tails are _____________ to each other and ________________ by water.
Figure 3.1 Pg. 82 *Correctly color code and identify the name for each part of the cell membrane.
Letter
_____
_____
_____
Name/Color
Phospholipid bilayer
Carbohydrate Chain (red)
Fatty acid tails (orange)
Letter
_____
_____
Name/Color
Protein (yellow)
Phosphate Heads (blue)
Top of Figure 3.1 in Biology Book
The cell membrane is made of ______ phospholipid layers embedded with other molecules, such as
________________________, ______________________________ and _________________________.
Selective Permeability (pg 83)
The cell has the property of selective permeability, which means it allows __________, but not all,
_________________ to cross. Selective permeability enables a cell to maintain ______________ in spite
of unpredictable, changing conditions ______________ the cell.
Osmosis (pg86)- is the diffusion of ____________ molecules through a selectively permeable
membrane moving from an area of _____________ water concentration to an area of _________water
concentration.
The effect of Osmosis is shown BELOW.
Label and Define using Figure 4.3 on Pg 86 (look at arrows)
Label ___________________
___________________
Define _________________ ________________
____ _____________
_ ______________
Facilitated Diffusion (pg 87)-
This is the diffusion of molecules _____________
a membrane through transport
_______________. The word facilitate means “to
make ____________.” The molecules move
___________ a concentration gradient, requiring
_________ energy expenditure by the cell.
Color the internal environment (inside cell) yellow. Color
the transport proteins red and the substance being moved
blue.
Protein
Substance
___________________
________________
________________
Active Transprt (pg 89)-
This drives molecules across a membrane from a
region of __________ concentration to a region
of ___________ concentration using ENERGY.
Draw arrows to indicate where the molecules move in
the picture below for active transport.