part 3: homeostasis and cell transport (chapter 5)
DESCRIPTION
Which types of molecules can move through the membrane without energy? Small, nonpolar (hydrophobic) molecules Examples: O 2, CO 2, H 2 O, lipidsTRANSCRIPT
Part 3: Homeostasis and Cell Transport (Chapter 5)
Passive Transport
• NO ENERGY REQUIRED to move substances across membrane from a higher concentration to a lower concentration
• Types:1. Diffusion2. Osmosis3. Facilitated Diffusion4. Diffusion through Ion Channels
•Involves the movement of molecules across the cell membrane without an input of energy by the cell.
Which types of molecules can move through the membrane
without energy?• Small, nonpolar (hydrophobic) molecules
• Examples: O2, CO2, H2O, lipids
Diffusion
Osmosis
Hypotonic Isotonic Hypertonic
Facilitated Diffusion
Ion Channels
• Active transport • moves molecules across the cell
membrane from an area of lower concentration to an area of higher concentration (against concentration gradient)
• requires cells to use ENERGY (ATP)• Some types of active transport are
performed by carrier proteins called cell membrane pumps.
Active TransportCell Membrane Pumps and Vesicles
Example: Sodium-Potassium Pump
Sodium-Potassium Pump
Endocytosis and
Exocytosis