Membrane Transport Flashcards
Isotonic:
Interstitial fluid is the same concentration as the cytosol; no net movement of water
Hypotonic:
Interstitial fluid has higher water concentration than cytosol; water enters cell
Hypertonic:
Interstitial fluid has lower water concentration than cytosol; water leaves cell
The passive movement of water through a semipermeable membrane is called _________.
Osmosis
Passive vs active processes?
Passive: does NOT require ATP; moves substances DOWN the concentration gradient. Active: does require ATP; moves substances UP the gradient
Diffusion vs osmosis?
Both are PASSIVE. Diffusion: movement of solutes. Osmosis: movement of water across semipermeable membrane
Simple diffusion vs facilitated diffusion?
PASSIVE. Simple: happens w/o transport protein; NONPOLAR. Facilitated: needs transport protein; POLAR
Channel-mediated vs carrier-mediated?
PASSIVE. Channel: ion moves thru channel. Carrier: small POLAR molecule moved by carrier proteins
Active transport vs vesicular transport?
Both ACTIVE. Active: ion/small molecule moved AGAINST its concentration gradient. Vesicular: involves a vesicle
Exocytosis vs endocytosis?
Both VESICULAR TRANSPORT. Exocytosis: vesicle releasing contents from cell; endocytosis: vesicle formed as material is brought into a cell
Phagocytosis vs pinocytosis vs receptor-mediated endocytosis?
All ENDOCYTOSIS. Phagocytosis: cellular eating. Pinocytosis: cellular drinking. Receptor-mediated endocytosis: receptor required
Primary vs secondary active transport?
Primary: energy source from ATP. Secondary: Energy source from movement of another substance
Symport vs Antiport?
Both SECONDARY active transport. Symport: two substances moved in SAME direction. Antiport: two substances moved in OPPOSITE directions
What is the ratio of sodium ions to potassium ions that are moved with their pump?
1:2:3 – 1 ATP TO PUMP 2 K INTO CELL AND 3 Na OUT OF CELL
Their is more _____ outside the cell.
Sodium
