AP BIOLOGY
NAME: ____________________________
MS. WEST
DATE: ___________________ PER: ____
CH. 7 (C)
TRANSPORT PROCESSES (cont.)
 Cell membranes are held together by weak ________________ interactions.
 O2, CO2, & nonpolar (______________) substances can dissolve across the membrane.
 IONS (________________) & POLAR (_________________) molecules need aid from
_____________ ______________.
 Saturated vs unsaturated phospholipids: [LATERAL MOVEMENT of ___________]
 DO 7.5 in H.O.S.G.(tan)
o Recall, an ISOTONIC solution (___________ the cell) is one in which the
concentration of non-penetrating _____________ (NPS) is ____________ to the
concentration of NPS _____ the cell.
o Recall, a HYPERTONIC solution (___________) is one in which the concentration
of NPS is _____________ in the surrounding solution than that _____ the cell.
o Recall, a HYPOTONIC solution (___________) is one in which the concentration
of NPS is _____________ in the surrounding solution than that _____ the cell.
~ An ISOTONIC solution is the most _____________ for a cell.
~ A HYPERTONIC solution surrounding a cell, could cause a cell to ___________
water, and eventually ______________!
~ A HYPOTONIC solution surrounding a cell, could cause a cell to _________
water, and eventually _____________!
…UNLESS, a cell has ____________________ to prevent this!
[Ex: ________________________________________________]
 Most IDEAL osmotic environment for:
 ANIMAL CELLS - ______________ Why? __________________________________
 PLANT CELLS - ______________ Why? ___________________________________
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 TRANSPORT PROCESSES
 PASSIVE TRANSPORT: (_____________ _____)

DIFFUSION (____________ ____________)

OSMOSIS (_____________ ____ ___________)

FACILITATED DIFFUSION (_________ ____ _____________)
 ACTIVE TRANSPORT: (_____________ _____)

ACTIVE TRANPORT
 TRANSPORT of LARGE PARTICLES:

EXOCYTOSIS

ENDOCYTOSIS
o PHAGOCYTOSIS (_________ _____________)
o PINOCYTOSIS (_____________)
 FACILITATED DIFFUSION:
[“facilitated” = _____________...by what? _______________]
o A form of _____________ transport because it does _______ require
___________! ...BUT, it does need ________ from _____________!
o Recall, many POLAR molecules and IONS ______________ directly move
across the lipid bilayer [WHY?! ___________________________________________]
o …SO, with the help of ______________ proteins that span the membrane,
some of these substances can _____________ across.
o These TRANSPORT _______________ are VERY specific and ONLY
______________ particular substances but not others.
 2 types of TRANSPORT PROTEINS:
 ______________ PROTEINS
 ______________ PROTEINS
 CHANNEL PROTEINS: provide a TUNNEL/_______________ that allow
specific _________________ or ions across the _________________.
o Ex: AQUAPORINS are ____________ CHANNEL PROTEINS.
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o Ex: ION CHANNELS function as GATED CHANNELS that have a
“____________” that will ____________ or ____________ with a particular
_______________.
 CARRIER PROTEINS: undergo a subtle change in _____________ & envelops
the substance, and then “spits” it out on the other side of the
_________________.
 ACTIVE TRANSPORT:
[“active” = _______________________]
** __________  __________ **
o The ONLY transport process that REQUIRES _____________/_______!
o The ONLY transport process that moves substances AGAINST their
concentration ______________ [“_______”], from an area of ___________
concentration of solute to an area of ___________ concentration of solute.
o Uses ______________ PROTEINS to move solutes _____________ their
concentration gradient.
 ALL these TRANSPORT PROTEINS are ______________ proteins that “pick
up” and move the substances across the membrane.
 Where does the ENERGY needed come from?
 ____________!
o Ex: SODIUM-POTASSIUM PUMP – exchanges ____________ ions for
_____________ ions across the membrane of ______________ cells. [Fig.7.16]
 Results in an ____________ in K+ conc & a _____________ in Na+ conc
within ___________ cells.
 This transport system pumps ions ____________ steep concentration
gradients.
 Sodium ion conc is HIGH ___________ the cell & LOW ___________
the cell; Na+ moves outside the cell (_______-->________ = __________
transport).
 Potassium ion (_____) conc is ________ outside the cell & _________
inside the cell; K+ moves into the cell (_______-->________ =
__________ transport).
 ALL cells have VOLTAGE across their plasma membranes.
 VOLTAGE – electrical _____________ energy – a separation of
____________ charges.
 This voltage, is called MEMBRANE ________________, & acts like a
_____________, an energy source that affects the traffic of all charged
substances across the membrane.
o Because the inside of the cell is NEGATIVE compared to outside, the
membrane potential favors the _____________ transport of CATIONS into
the cell & __________ out of the cell…
o THUS, ____ forces drive the diffusion of IONS across a membrane:
 A CHEMICAL FORCE – the ION’S _______________ gradient.
 An ELECTRICAL FORCE – the effect of the _____________ potential on
the ion’s _______________.
 The combination of these forces acting on an ION is called the
ELECTROCHEMICAL _______________ (an ION’s “concentration
gradient”)
 Moving water molecules, other small solutes & non-polar molecules across the
cell membrane can be done through the process of _______________,
_______________, __________________ _________________, and ______________
________________, where ________________ proteins pump or carry the
substances across the membrane.
 BUT, moving _______, __________ molecules & LARGER MOLECULES, such
as _________________ and ___________________, uses ______________ in the
process of __________________ & __________________.
 EXOCYTOSIS:
[“ex” = _________; “cyto” = ___________;
 _________________________]
 cells use VESICLES (transport
_______________) to move large substances
from _______________ the cell to ________________ the cell!
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 ENDOCYTOSIS:
[“endo” = ______; “cyto” = ___________;  _________________________]
 cells form ________________ from the _____________ _________________ to take
______ large ________________ from _______________ the cell ____________ the
cell!
o TYPES of ENDOCYTOSIS:
 PHAGOCYTOSIS: when a cell engulfs a particle by extending the cell
membrane around it and packaging it within a membrane-enclosed
sac called a _________ vacuole.
 PINOCYTOSIS: when a cell "gulps" droplets of fluid into the cell using
____________.
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