Chapter 6 Flashcards
What is cellular respiration? What is it’s primary goal?
The collection of metabolic reactions within cells that breaks down food molecules and uses the liberated free energy to synthesize ATP
Goal- to transform the potential energy found in food molecules into a form that can be used for metabolic processes (ATP)
Why is glucose a good fuel molecule?
Contains an abundance of C-H bonds
What type of reaction is cellular respiration?
Combustion of glucose
What is the difference between NAD+ and NADH?
NAD+ is oxidized
NADH is reduced
What are the three phases of cellular respiration?
- Glycolysis
- Pyruvate Oxidation and the citric cycle
- Oxidative phosphorylation
What is the composition of the mitochondrion?
It has an outer and inner membrane
Intermembrane space (inbetween inner and outer)
Matrix (inner acqeous solution in inner membrane)
What is glycolysis?
10 sequential enzyme catalyzed reactions that lead to the oxidation of the six-carbon sugar glucose, producing two 3 carbon pyruvates
Doesn’t need oxygen
Found in archae, bacteria, eukarya (all 3)
2 ATP to start but produces 4 ATP
What is pyruvate oxidation?
Links glycolysis and the citric acid cycle
Moves the pyruvate into the mitochondria matrix
Converts pyruvate into acetyl coA through many steps:
Carboxyl group of pyruvate is lost then remaining two carbons is oxidized producing acetate
This acetyl group reacts with coenzyme Ato produce acetyl CoA
What is the citric cycle?
Eight enzyme catalyzed reactions
Starts with the acetyl CoA
Then CoA is released and participates again in pyruvate oxidation
Results in the oxidation of acetyl groups to carbon dioxide accompanied by the synthesis of ATP; NADH; and FAD
All carbon atoms have been oxidized and released as carbon dioxide
Results in 2 ATP
What two steps are in oxidative phosphorylation?
Electron transport chain
Chemiosmosis
What is the electron transport chain?
Converts potential energy in NADH and FADH2 into proton-motive force
Complex I, II, III, IV
Two mobile electron shuttles facilitate electron flow
No atp produced yet (just delivers electrons along a chain of electron carriers until they are donated to oxygen, producing water)
What is chemiosmosis?
It harnesses the proton-motive force created in the electron transport chain to do work
Energy for chemiosmosis comes from the oxidation of energy rich molecules such as NADH by the electron transport chain
What is oxidative phosphorylation?
The mode of ATP synthesis that is linked to the oxidation of energy-rich molecules by an ETC
Relies on action of large multi protein called ATP synthase
Results in 34 ATP
What is ATP synthase?
Lollipop shaped complex consisting of a basal unit which is embedded into the inner membrane of mitochondrion and has a head piece that sticks out into matrix
What are uncouplers?
Ionophers that are very toxic because of their ability to inhibit oxidative phosphorylation
