The Cell: Transport Mechanisms and Cell Permeability

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The Cell: Transport Mechanisms and Cell Permeability
1. Molecular motion: A and D

2. Velocity of molecular movement: B and C

4. Size of pores. Solubility in the lipid portion of the membrane and/or presence of membrane “carriers” for the substance(s).

5. Glucose- (a) move into the sac
Albumin- (c) no movement
Water- (b) move out of the cell
NaCl- (a) move into the celll

7. Hypertonic- C- crenated
Isotonic- B
Hypotonic- A- hemolysis, bursting open due to swelling

8. A) faster diffusing gas- NH4OH
B) Precipitate forms closer to the HCL side.

9) If a cell must use ATP to directly or indirectly transport the molecule it is active transport, if ATP is not needed for the transport it is passive.

10) Passive processes: a, c, eActive- b, d, f

11) The tube was in a dialysis sac which was in water. Since water moves down its concentration gradient it diffused from the beaker into the sac, where its concentration was lower. This caused the fluid column to rise in the tube.

12) Define the following terms:
Diffusion: Movement of molecules from an area higher concentration to an area of lower concentration.
Osmosis: Diffusion of water through a water permeable membrane from higher concentration to an area of lower water concentration.
Simple diffusion: Movement of molecules from higher concentration to a lower concentration. Uses kinetic energy of the diffusing molecules.
Filtration: Movement of molecules across a membrane from an area of higher hydrostatic pressure to an area of lower hydrostatic pressure.
Active Transport: Transport systems that require the cell to provide ATP.
Phagocytosis: Intake of extracellular particles by extending the plasma membrane out around the particle. “Cell eating.”
Fluid-phase Endocytosis: Intake of extracellular fluids by vesicle formation. “Cell drinking.”
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