Guided Reading Plasma membrane section 7.2
1. The _______________ is the flexible boundary of a cell that separates a cell from its surroundings. It
allows __________ to enter the cell and _____________ to be removed. Keeping this balance is called
_______________.
2. To keep this balance the cell membrane allows some molecules to enter the cell and keeps other out, this
is called _______________ ______________.
3. A ________________ is made up of glycerol, two fatty acids and a phosphate group. The plasma
membrane is made up of __________ layers of _________________ arranged back to back called a
_____________ layer.
4. The 2 phospholipid layers are arranged so the ________ heads are facing out and the _________ tails
are facing in.
5. The phospholipid bilayer makes a barrier that is ___________ on the outside and ____________ on the
inside. This arrangement makes it so it is harder for ___________________ molecules to move through
the membrane.
6. The organization of the plasma membrane is called a ___________ ____________ model.
Guided reading Cell Transport section 8.1
1. The plasma membrane is ____________ __________meaning only certain molecules can pass in and
out of the cell.
2. ____________ is the only substance the plasma membrane always allows in or out. The movement of
water from an area of ________ concentration to an area of __________ concentration is called
_____________.
3. In a ____________ solution water moves in and out of the cell at the same rate this allows cells to keep
__________ shape.
4. In a ____________ solution more water enters the cell than leaves so the cell will _____________.
5. In a ____________ solution more water leaves the cell than enters, so the cell will ___________.
6. When a cell uses no energy to move substances through its membrane it is called ______________
transport.
7. When special proteins in the plasma membrane move help move large molecules across the membrane
the process is called ______________ _____________.
8. In __________________- _______________ particles are moved across the cell membrane against a
force. So the substance moves from an area of ___________ concentration to an area of
_____________ concentration. This process requires ________________.
9. _________________ is a process in which a cell engulfs large molecules and takes them into the cell.
_______________ is the reverse of endocytosis.
Use p. 177-178 in your Biology textbook to label and color-code each of the following:
Part
Polar head
Nonpolar tail
Carbohydrate chains
Membrane transport proteins
Cholesterol
Phospholipid bilayer
Color
Function
Homeostasis within an organism
Use the following concept maps to illustrate how organisms maintain homeostasis, the internal
balance, of water, blood glucose and temperature.
1. Temperature (p. 896)
Blood vessels ___________
Blood flow _____________
Body heat is ____________
Body temperature falls
Body temperature rises
Blood vessels ___________
Blood flow _____________
Body heat is ____________
Glands produce _________,
which dries on the skin.
2. Blood Glucose (p. 932)
Eat
food
Liver and
muscles take
in
_________
Pancreas
releases
__________
Blood glucose
levels ______
Pancreas
releases
__________
Liver cells
release
__________
Blood
glucose
levels _____
3. Water (p. 931)
Work out and
sweat
_________ water
in your blood
________________
senses concentration
of _________ in
your blood
Blood water
level ________.
It stimulates
__________ gland
to make _________.
ADH causes kidney
cells to reabsorb
_________ from
_____________.