1. What biochemical feature of a phospholipid molecule allows phospholipids to spontaneously form closed compartments when placed in an aqueous solution?
a) they are amphipathic
b) they are charged
c) they are spherical
d) they have a single fatty acid tail
2. Other than phospholipids, what molecule do cells use to alter the fluidity of biological membranes?
3. What distinguishes active transport from passive transport?
a) active transport can utilize channel proteins
b) passive transport does not utilize carrier/transporter proteins
c) active transport requires the input of energy
d) active transport only occurs at the plasma membrane
4. In the case of active transport, the Na+/K+ pump undergoes a sequence of conformational changes that allows the movement of Na+ and K+ across a membrane against their electrochemical gradients, while in the case of ER protein import SRP undergoes a sequence of conformational changes to allow the signal sequence to interact with the translocation pore. What drives these conformational changes?
a) hydrolysis of a high energy phosphate bond
b) binding of a solute or protein
c) both
d) neither
5. Is protein import into the ER co-transcriptional, or co-translational?
1. What biochemical feature of a phospholipid molecule allows phospholipids to spontaneously form closed compartments when placed in an aqueous solution?
a) they are amphipathic
b) they are charged
c) they are spherical
d) they have a single fatty acid tail
2. Other than phospholipids, what molecule do cells use to alter the fluidity of biological membranes?
3. What distinguishes active transport from passive transport?
a) active transport can utilize channel proteins
b) passive transport does not utilize carrier/transporter proteins
c) active transport requires the input of energy
d) active transport only occurs at the plasma membrane
4. In the case of active transport, the Na+/K+ pump undergoes a sequence of conformational changes that allows the movement of Na+ and K+ across a membrane against their electrochemical gradients, while in the case of ER protein import SRP undergoes a sequence of conformational changes to allow the signal sequence to interact with the translocation pore. What drives these conformational changes?
a) hydrolysis of a high energy phosphate bond
b) binding of a solute or protein
c) both
d) neither
5. Is protein import into the ER co-transcriptional, or co-translational?
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