Lecture 14: Cellular Respiration (Part 2) Flashcards
What are the two linked components required for oxidative phosphorylation?
- Electron Transport Chain (ETC)
- ATP Synthase
Why is oxidative phosphorylation called that way?
because it links the phosphorylation of ADP with NADH and FADH2 oxidation
What is the oxidative part of oxidative phosphorylation?
involves the electron transport chain
What is the phosphorylation part of oxidative phosphorylation?
its the phosphorylation that occurs via ATP synthase
What are the two linked processes that happen in oxidative phosphorylation?
- The creation of an electrochemical proton gradient by the ETC
- The synthesis of ATP by chemiosmosis using ATP synthase
What is the ETC made of (general components)?
a collection of chemicals in (or associated with) the inner mitochondrial membrane.
These chemicals are:
A. Proteins
B. Organic Molecules
C. Metal Ions
What do the organic molecules and metal ions act as in the ETC?
cofactors in redox reaction.
What is the structure of the ETC?
A. 4 types of respiratory complexes (I-IV).
B. Cytochrome C (Cyt C)
C. Ubiquinone(Q)
What is Cytochrome C?
a peripheral protein that acts alone (not part of a complex).
What is Ubiquinone(Q)?
a small organic molecule that can move throughout the membrane
What does the ETC do?
- Accepts electrons from electron carriers.
- The electrons are transferred from one component in the chain to another through a series of redox reactions.
What happens to the electrons as they move through the ETC?
The high potential energy of the electrons is gradually decreased after each transfer.
How do you call the last electron acceptor of the ETC?
the terminal electron acceptor
Where does the potential energy of the electrons is transferred to as it decreases along the ETC?
it is converted into a H+ ion electrochemical gradient.
Which respiratory complex does not pump H+ ions across the membrane?
complex II
What is a respiratory complex and what is it made of?
protein groups in which the components of the ETC are organized into
Proteins in complexes contain cofactors that act as redox centers: accept and donate electrons.
complexes range in size, number and composition of subunits used, and the cofactors used as redox centers.
By which genome are most of the polypeptide of the protein complexes encoded by? By Which genome are the others encoded by?
Most polypeptides are encoded by the nuclear genome but some are encoded by the mitochondrial genome.
What is the name of complex I of the ETC?
NADH-Q oxidoreductase
What is the name of complex II of the ETC?
Succinate-Q oxidoreductase
What is the name of complex III of the ETC?
Q-Cyt c oxidoreductase
What is the name of complex IV of the ETC?
Cyt c Oxidase
How many polypeptides are encoded by the nuclear genome in complex I?
43
How many polypeptides are encoded by the nuclear genome in complex II?
4
How many polypeptides are encoded by the nuclear genome in complex III?
11
How many polypeptides are encoded by the nuclear genome in complex IV?
13
How many polypeptides are encoded by the mitochondrial genome in complex I?
7
How many polypeptides are encoded by the mitochondrial genome in complex II?
0
How many polypeptides are encoded by the mitochondrial genome in complex III?
1
How many polypeptides are encoded by the mitochondrial genome in complex IV?
3
Which cofactors are in complex I?
FMN
Fe-S
Which cofactors are in complex II?
FAD
Fe-S
Which cofactors are in complex III?
Heme
Fe-S