Movement Across Boundaries Flashcards
Osmosis and diffusion are ______ processes
Random molecular motion
Integral proteins are _______ mechanism
Transport
Large things pass through the membrane through ____
Endocytosis
T or F. Diffusion is random consequence of temperature.
True
What is the rule of diffusion?
Substance moves from areas of high free energy to low free energy until it reaches equilibrium
What is osmosis?
The diffusion of water
What are types of movement across membranes?
Passive and active
What is passive transport?
Diffusion by random molecular motion
Define: active transport
Transport through the cell using energy
T or F. Active transport can move from low free energy to high free energy
True.
What are the 3 ways that things can enter the cell?
Through random molecular motion, transport mechanisms and endocytosis
What are the three types of ports?
Antiport, symport and uniport
How many molecules go through the uniport?
One
What happens in a symport?
It takes two molecules going in the same direction
What happens in an antiport?
Two molecules go through in different directions
What is an example of an antiport, a uniport and a symport
Antiport: sodium potassium pump
Uniport: calcium pump
Symport: proton pump
Describe the method of the potassium pump.
- 2 potassium ions bing at site causing phosphate to fall off
- ATP binds at site 5
- 3 sodium ions bind at site 1
- ATP donates a phosphate group to site 4, turning to ADP
- 3 sodium ions leave the cell
- Opens channel so 2 potassium pumps can bind and repeat.
Define: phosphorylation
When a phosphate is added to a molecule
When a phosphate is removed, it is called ____
Elephosphorylation
Kinase _____ phosphate whereas phosphatase _______ phosphate.
Adds, removes
One way of inhibiting the sodium potassium pump is by ________
Cardiac glycosides bing to site 3 and kill the pump
Outside the cell there is ____ sodium and inside the cell there is _____ potassium
Higher, higher
