Download Reading Pages 136-141: Topics to focus on—

Reading Pages 136-141, and 143: Topics to focus on—
1. List 4 ions that need to cross the membrane.
Na+, K+, Ca2+, Cl2. List 4 other items that have to pass the membrane.
Sugars, amino acids, nutrients, waste leaves, O2, CO2
3. Define and explain selectively permeable.
Take up some items and exclude others—does not let all things
pass—dependent on structure of molecule
4. Is the membrane hydrophilic or hydrophobic?
Hydrophobic
5. Define transport protein. Do transport proteins have
specificity? Tunnel to allow hydrophilic items to pass the
membrane that cannot get through the lipid bilayer—very
specific (allow glucose but not fructose)
6. Define and explain diffusion.
Molecules spread out into available space—random for each
molecule but directional for population of molecules
7. What is dynamic equilibrium? When is it reached? What
does this mean for transport? Both solutions have equal
concentrations—the same amount is moving in one direction
as in the other direction
8. Define concentration gradient.
When molecules want to move from high concentration to low
concentration—difference in concentrations over an area
9. What direction of concentration gradient does a substance
move (up or down)? Explain.
Down because it wants to spread out
10.
Disorder
Define entropy.
11.
Define passive transport.
Diffusion across a membrane NO ENERGY expended (Ex. Water)
12.
Define hypertonic, isotopic, and hypotonic.
Hypertonic-Higher concentration of solutes
Hypotonic-Lower concentration of solutes
Isotonic-equal concentration of solutes
13.
Understand the example of distilled water, tap water,
and seawater.
 Distilled water is hypotonic is tap water. Tap water is then
hypertonic to the distilled water.
 Tap water is hypotonic to seawater. Seawater is hypertonic
to tap water.
 Distilled water is hypotonic to seawater. Seawater is
hypertonic to distilled water.
14.
Define osmosis.
Diffusion of WATER across a selectively permeable
membrane—passive transport (no energy)
15.
How do cells WITHOUT cell walls react in:
a. Hypertonic solutions
b. Hypotonic solutions
c. Isotonic solutions
16.
How do cells WITH cell walls react in:
a. Hypertonic solutions
b. Hypotonic solutions
c. Isotonic solutions
17.
Understand Figure 8.11.
18.
Define osmoregulation.
Control of water balance—needed for organisms that live in
hyper or hypo environments
19.
Define turgid.
Firm—slight expansion of water going in
20.
Define flaccid.
Limp—wilted—in isotonic solution for plants
21.
Define plasmolysis.
Membrane pulls away from the cell wall—shriveled—lethal to
the plant—in hypertonic solution
22.
Difference between facilitated and active.
Facilitated: transport proteins helping ions and polar molecules
across the membrane—passive bc its still DOWN the conc.
gradient
Active: using energy to pump a molecule across a membrance
UP its concentration gradient (use ATP for the energy)
23.
Define exocytosis.
Secrete macromolecules by fusion of vesicles (from the golgi)
with the membrane
24.
Define endocytosis.
Take in macromolecules—form new vesicles from the
membrane to the destination
25.
Define phagocytosis.
Type of endocytosis—engulf or eat large molecules
26.
Define pinocytosis.
Type of endocytosis—gulp or drink fluid or solutes