Flashcards in Ch. 14 Deck (43)
Which of the following drives the production of ATP from ADP and Pi by ATP synthase?
A proton gradient
Which of the following processes involves a membrane?
What is the main chemical energy currency in cells?
In the electron transport chain, as electrons move along a series of carriers, they release energy that is used to:
pump protons across a membrane.
The organelles that produce ATP in eukaryotic cells:
evolved from bacteria engulfed by ancestral cells billions of years ago.
.Which of the following organisms do not have mitochondria in their cells?
In mitochondria, with the complete breakdown of glucose, about how many molecules of ATP can be produced for each molecule of glucose oxidized?
Mitochondria can change their location, shape, and number in the cell to suit the needs of a cell.
Which of the following is NOT true of mitochondria?
They are replaced by chloroplasts in plants.
The outer membrane of a mitochondrion is permeable to all small molecules, including small proteins.
.In a eukaryotic cell, where are most of the proteins for the electron transport chain located?
In the mitochondrial inner membrane
Which of the following is not a direct source of fuel for mitochondria?
The electron transport chain accepts high-energy electrons from:
NADH and FADH2
Which of the following statements is true about the electron transport chain?
Electrons start out at very high energy and lose energy at each transfer step.
The movement of electrons through the electron transport chain:
pumps protons across the inner mitochondrial membrane.
In mitochondria, what is the final electron acceptor in the electron transport chain?
Molecular oxygen (O2)
The electron transport chain pumps protons:
from the matrix to the intermembrane space.
It is energetically favorable for protons to flow in which direction?
From the intermembrane space to the mitochondrial matrix
When protons move down their electrochemical gradient into the mitochondrial matrix, they:
can either produce or break down ATP depending on the magnitude of the electrochemical proton gradient.
What occurs when ATP synthase pumps H+ across a membrane against the electrochemical proton gradient?
ATP synthase cleaves ATP to form ADP and Pi
The proton gradient can drive the active transport of metabolites into and out of the mitochondrion.
What is the ratio of ATP and ADP concentrations in the cytosol of a cell?
High ATP/ADP ratio
Why does a single molecule of NADH result in the production of more ATP molecules than a single molecule of FADH2 via oxidative phosphorylation?
FADH2 feeds its electrons into the electron transport chain further along the chain.
is more efficient at generating energy than a gasoline-powered engine.
.In the electron transport chain, what provides the main reservoir for protons that are pumped across the membrane?
Which of the following statements is NOT true of electron transfer in the electron transport chain?
When an electron carrier accepts an electron, it becomes oxidized.
When the difference in redox potential between two pairs of molecules is highly positive, then the transfer of the electrons is:
As electrons move through the electron transport chain, they are passed from:
a carrier molecule of lower electron affinity to a carrier molecule of higher electron affinity.