Cellular Transport

Biology I Factoids

Factoid 65

• The cell membrane is selectively permeable. That means some stuff can enter and some stuff can leave.

Factoid 66

• The phospholipid head is hydrophilic (water loving) and the phospholipid tail is hydrophobic (water hating).

Factoid 67

• Passive transport does not require energy and moves stuff from a high concentration to a low concentration, but active transport does require energy and it moves stuff from a low concentration to a high concentration.

Factoid 68

• The three types of passive transport is simple diffusion, facilitated diffusion, and osmosis.

Factoid 69

• Active transport includes exocytosis (big stuff leaving the cell), endocytosis (big stuff entering the cell), and various pumps.

Factoid 70

• When molecules on both sides of the membrane move in both directions, the system has reached equilibrium.

Factoid 71

• Simple diffusion involves the movement of molecules from a high concentration to a low concentration. It can be any substance.

Factoid 72

• Facilitated diffusion is the movement of molecules through a channel protein from high concentration to low concentration.

Factoid 73

• Osmosis is the movement of water from high concentration to low concentration.

Factoid 74

• A cell placed in a hypotonic solution will swell. A cell in a hypertonic solution will shrink. A cell in an isotonic solution will stay the same.