Chapter 5 Quiz Flashcards
Diffusion Definition
Movement of molecules from HIGHER to LOWER concentrations
Osmosis Definition
The diffusion of water across a differentially permeable membrane
Factors that influence rate of diffusion
temperature, pressure, molecular size, electrical currents.
Endocytosis Definition
A way substances can enter the cell. Intracellular vesicle forms
Pinocytosis Definition
When a liquid or ‘small’ molecule enters
Exocytosis Definition
The way substances can exit a cell. Vesicle fuses with membrane
Isotonic Definition
No net movement of water within the cell
Hypertonic Definition
Water leaving the cell
Hypotonic Definition
Water entering the cell
Passive Transport
molecules are able to slip between the hydrophilic heads of the phospholipids and pass through the hydrophobic tails of the membrane.
Aquaporins
Special water channels that allow large amounts of water to cross the membrane
facilitated diffusion
Substances requiring carrier proteins but NO energy expenditure to move with a concentration gradient across a membrane
Active Transport
Energy is required, moving against concentration gradients, large or polar substances, and ions
