DNP Review Exam Questions with 100% Correct Answers

What Does DNP Actually Do? Correct Answer DNP is a weak acid due to its -OH group, •This means that some of the time it can shed its proton, becoming -O-+ H+. This is unlike HCl, which is a strong acid, and thus completely dissociates in water. You have created some artificial membrane vesicles that have a higher pH inside than the aqueous solution outside. To sample 1 of these vesicles you add a little HCl, and to the other (sample 2) you add some DNP and then measure the internal pH of the vesicles. What do you predict would happen? Correct Answer remain unchanged in 1 but decrease in 2. When protonated (carrying its H+proton) as you saw in the figure, DNP will be uncharged and very hydrophobic. It is hence readily soluble in lipid bilayers such as those enclosing these vesicles (and those of the mitochondrial inner membrane).Thus DNP can readily carry protons across the membrane from a higher concentration (lower pH) outside, and release them to the lower concentration (higher pH) inside. This equilibrates the pH inside and outside. HCl cannot do this, because it is not hydrophobic, and its charged ion species (H+and Cl-) cannot cross lipid bilayer structures. You incubate isolated intact mitochondria in a buffered solution with succinate, and ADP plus Pi. You add oligomycin(the ATP synthase inhibitor), then the compound DNP (2,4-dinitrophenol), and examine the effect on oxygen consumption and the production of ATP. What do you predict? Hint: On taking DNP as a weight-loss drug, people experienced weakness, sweating, and hyperventilation Correct Answer Oxygen will be consumed but no ATP will be produced. DNP acts as an uncoupler! And working like crazy' needs a lot of________, and generates a lot of___________ (fill in the blanks) Correct Answer Increased Oxygen consumption -to pump all those protons back out, oxygen has to be there to accept the electrons passing through the ETC.•Heat generation -Energy converted from one form to another (second law of thermodynamics) • Does this fit with the effects you know that DNP has on people? Yes! rapid breathing because they need oxygen, sweating from the increase in body temperature due to the heat generated, and fatigue because ATP stops being made, even though lots of calories are being burned. DNA polymerase Correct Answer is an enzyme that catalyzes DNA synthesis DNA Polymerase II Correct Answer extends the leading strand