In the highly simplified diagram below, the energy landscape of secretory vesicle fusion to the plasma membrane is shown in the presence or absence of appropriate SNARE complexes. Which curve (A or B) do you think corresponds to the presence of SNARE complexes? Write down A or B as your answer.

Question

Quizplus · Accepted Answer

Similar to enzymes and other catalysts, SNARE complexes facilitate membrane fusion by lowering the free-energy barrier. They also transition into a stable conformation at the end of the process, requiring the energy of ATP hydrolysis to reset. Thus, they also push the process forward by stabilizing the products.

In the Highly Simplified Diagram Below, the Energy Landscape of Secretory