carrier proteins: facilitated and active transport
Summary: Simple diffusion
- transports Small molecules that are non-polar that fallow concentration gradient and don't require energy or carrier proteins.
Active transport: 'pumps'
-Are proteins involved in active transport because they use energy to move a substance against its concentration gradient. Type of pump(s): Sodium-Potassium pump
Active transport: passage
-both carrier molecules and an expenditure of energy are required to transport substances against their concentration gradient.
facilitated: definition
-to make something easier
Summary: facilitated transport
-transports small molecules that are not lipid-soluble (polar or charged) and fallow the concentration gradient. -molecules combine with carrier proteins and energy is not required
Active transport: Sodium potassium pump
-Moves three sodium ions (Na+) to the outside of the cell and two potassium ions (K+) to the inside of the cell. -A change in carrier shape after the attachment and detachment of a phosphate group from the break down of ATP allows the carrier to combine alternately with sodium and potassium ions. -The sodium-Potassium pump results in both a solute concentration gradient and an electrical gradient for these ions to cross the plasma membrane. (SEE DIAGRAM)
Facilitated transport: dont need energy (ATP)
-Neither diffusion or facilitated transport needs energy (ATP) because the molecules are moving down their concentration gradient.
facilitated transport: glucose amino acids
-The passage of glucose and amino acids is facilitated by the reversible combination with carrier proteins.
Active transport: passage of salt
-The passage of salt across a plasma membrane is primarily importance of cells. The Chloride ion (Cl-) crosses the plasma membrane because it is attracted to positively charged sodium ions (Na+). Cystic fibrosis: genetic disorder of chloride channel.
carrier proteins: facilitated
-These carrier proteins are specific (i.e. glucose, can pass much faster than other sugars). -After a carrier has assists a substance past the plasma membrane, it is free to assist the passage of other similar molecules.
Summary: Active transport
-Transports small/charged (ions) molecules. These molecules combine with carrier proteins and energy is required.
Facilitated transport
-is the use of plasma membrane carrier proteins to move a substance into or out of a cell from a high to low concentration (NO ENERGY REQUIRED). The carrier protein changes shape as solute crosses plasma membrane. (Protein carrier)
Active transport
-the use of the plasma membrane carrier to move a substance in or out of the cell from low to high concentration. (ENERGY REQUIRED)- to combine with the substances. -cells that are primarily involved with active transport have a large number of mitochondria. (protein carrier)
