cellular respiration

Question 1

As an electron passes through the electron transport chain, the energy it releases is used to pump __ out of the++, forming an electrochemical ___. When the

flow back down their gradient, they pass through an enzyme called ATP synthase, driving synthesis of ATP. This process is known as oxidative phosphorylation.

Answer 1

protons

mitochondrial matrix

gradient

ATP synthesis

oxidative phosphorylation

Question 2

There are two types of electron carriers that are particularly important in cellular respiration: NAD and FAD.

When NAD and FAD pick up electrons, they also gain one or more hydrogen atoms, switching to a slightly different form:

NAD+ + 2e- +2H+ –> NADH + H+

FAD + 2e- +2H+ –>FADH2

And when they drop electrons off, they go neatly back to their original form.

The reactions in which NAD and FAD gain or lose electrons are examples of a class of reactions called redox reactions.

Answer 2

NAD

FAD