Define the following terms: uniport carriers, cotransporters, symport carriers, and anti port carriers.
-uniport can only move one molecule
-cotransporter refers to a carrier that moves more than one molecule
-symport moves more than one molecule in the same direction
-antiport moves more than one molecule in opposite directions
Compare and contrast facilitated diffusion and simple diffusion.
Simple diffusion can directly cross the phosopholipid bilayer of a membrane.
Facilitated diffusion is a mediated transport.
Both are passive and move molecules down their concentration gradient.
Give example of molecules that might cross a membrane by facilitated diffusion.
Sugars and amino acids
What is active transport? What does it accomplish? Why does it require the input of energy?
Molecules moving against their gradient which requires a lot of energy. It creates a state of disequilibrium. Moving m In the sodium potassium pump, Na is getting pumped out while K is getting pumped in. In a neuron this would result in a neuron firing.
Distinguish between primary active transport and secondary active transport.
-primary active transport also known as ATPase(enzyme)
-secondary active transport uses ATP from primary active transport and usually is Na dependent
Diagram the structure and mechanism of the Na+-K+-ATPase as an example of primary active transport.
How is the relativity high extracellular Na+ used to drive transport of other molecule against their concentration gradient across a membrane?
By using cotransporters molecule will piggy back with it.
Give examples of how specificity applies to carrier-mediated transport.
The transporter(membrane protein) only allows a certain family of molecule through like GLUT.
How does competition relate to specificity?
Since transporters can move a family of molecules, the particular type that it wants could get beat out by a different molecule in the family.
Give an example of competitive inhibition.
When one molecule prevents the needed molecule from binding to a transporter.
example: maltose and glucose are in the same family(disaccharides) but compete with each other for binding sites.
Describe how the principle of saturation applies to carrier-mediated transport. Included a description of transport maximum.
As the substrate concentration increases the rate of transport increases until to reaches a max like the check out stands at the super market.
How can cells increase their transport capacity and avoid saturation?
Increase the number of carriers in the membrane.
The two primary modes of vesicular transport are _____ and _____.
phagocytosis and endocytosis
Describe the process of phagocytosis. What is a phagosome?
phagocytosis is the process of engulfing a bacteria or particle. A phagosome is the membrane bound vesicle that brings the particle to lyosomes.
How does endocytosis differ from phagocytosis?
-in endocytosis the membrane indents
-vesicles in endocytosis are much smaller
-endocytosis is an essential process alway occurring while phagocytosis must be triggered.
What is pinocytosis?
Active process that can be nonselective or selective, sucks in water
Explain the process of receptor-mediated endocytosis. What role does clathrin play? What is an endosome?