It is thought that the glucose transporter switches between two conformational states in a completely random fashion. How is it possible for such a system to move glucose across the membrane efficiently in a single direction?
What will be an ideal response?
Although the opening of the glucose transporter on one side of the membrane or the other is random, the binding of glucose into the binding site of the transporter is not a random event. The affinity between the glucose molecule and the transporter governs the binding event:
transporter + glucose ? transporter–glucose
At high glucose concentrations, the complex formation is favored; at low glucose concentrations, dissociation of glucose from the transporter is favored. So, as long as there is a large concentration gradient, efficient transport can occur by the simple rules of binding equilibria.
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Depolarization occurs due to the diffusion of K+ across a neuron plasma membrane
Indicate whether the statement is true or false.
The ability of animals to adjust to seasonal changes in temperature is called:a
acclimatization. b. estivation. c. homeostatic adjustment. d. torpor. e. hibernation.
Which of these is a copy of DNA that is used to direct the synthesis of a specific protein?
A. mRNA B. rRNA C. tRNA D. ribosome
There are 5 independently assorting genes named A, B, C, D and E. If you bred individuals with these genotypes: AABbCcddEE x AaBbCcDDEE, what would be the expected proportion of offspring that would have the following genotype: AABbccDdee?
a) 0 b) 1/16 c) 1/8 d) 1/32