Chapter 5 Flashcards
Define: Anaerobes
Capture and utilize energy by oxygen, independent metabolism like glycolysis and fermentation
Define: Aerobes
Use oxygen to extract more energy from organic molecules
In eukaryotes, using oxygen as energy takes place where?
In the mitochondrion
Mitochondria have the ability to synthesize what?
Proteins
What is mitochondrial fusion?
Mitochondria confused with one another
What is mitochondrial fission?
Mitochondria can split into two
What does the outer boundary of a mitochondria and contain?
Outer mitochondrial membrane and inner mitochondrial membrane
What is the inner mitochondrial membrane divided into?
Inner boundary membrane domain and outer domain
Describe the inner boundary membrane domain of the mitochondria
Rich in proteins, responsible for import of mitochondrial proteins
Describe the outer boundary membrane domain of the mitochondria
Interior of the organelle, is a series of invaginated membraneous sheets called cristae 
Define: Cristae
Invaginated membraneous sheets
The members of mitochondria and divide organelles into two compartments:
The matrix and the inter-membrane space
Where is the matrix in regard to the mitochondria?
Within the interior of mitochondrion
Where is the inter-membrane space in regard to the mitochondria?
Second between outer and inner membrane, high protein to lipid ratio
What does the mitochondrial matrix contain?
Ribosomes and several molecules of circular DNA
What does mitochondrial DNA do?
Manufactures their own RNAs and proteins
Net result of glycolysis
Two ATP and NADH
What is ATP composed of?
Adenine, a ribose, and three phosphate groups
Does oxidation add or remove electrons?
Remove
Does reduction add or remove electrons?
Add
What do electron carriers do?
Find and carry high energy electrons between compounds in a pathway
What is glycolysis?
First pathway used to break down glucose for energy
Where does glycolysis happen?
In the cytosol
What is the process and result of glycolysis?
Breaks down the six carbon ring of glucose into 2 3-carbon sugars- pyruvate
What is fermentation?
And anaerobic process, where NAD is regenerated from glucose
Where does fermentation happen in normal conditions?
In the cytosol
Where does fermentation happen when there is insufficient oxygen supply?
In the muscle
What do muscle cells ferment?
Lactate
What does fermentation use and produce?
2NADH into 2NAD
Where are the first steps of oxidative metabolism carried out?
In the cytoplasm
What does glycolysis produce?
Pyruvate, NADH, and to ATP
When pyruvate transported across inner membrane and is decarboxylated, what does it form?
Aceto-CoA
What is the form of pyruvate that enters the TCA cycle
Acetyl CoA
What is the tri carboxylic acid cycle?
Kreb cycle or citric acid cycle
What is the main source of energy for cells?
TCA cycle
What does the TCA cycle do to acetal-CoA
Harnesses available chemical energy of acetyl-CoA into reducing power of NADH
The two carbon acetyl group from acetyl-CoA is condensed with what to form what
Condensed with four carbon oxaloacetate to form a six carbon
What are the primary products of the TCA cycle?
FADH2 and NADH
What are FADH to an NADH used for?
They are fed into mitochondrial ETC and used for ATP formation
Turn the mitochondria take up all cytoplasmic NADH?
No
What is done with extra NADH?
Glycerol phosphate shuttle – electrons transferred from cytosolic NADH into DHAP Which forms glycerol – 3P which shuttles electrons and transfers them to FAD making FADH2
Process of ATP formation step one:
High energy electrons pass from NADH and FAD H2 through electron carriers that make up ETC 
Process of ATP formation step two
Control the movement of protons back across membrane, chemiosmosis
How many ATP are formed from each pair of electrons donated by NADH?
Three
How many ATP are formed from each pair of electrons donated by FADH2
Two
Define: Chemiosmotic mechanism
Mechanism for ATP synthesis where movement of electrons through etc result in a proton gradient across the bacterial, thylakoid, or inner mitochondrial membrane, with the gradient acting as high energy intermediate – linking oxidation of substrates to phosphorylation of ADP
What kind of molecules do mitochondria extract energy from?
Organic molecules
What do mitochondria use to drive the energy-requiring activities like ATP synthesis?
Ionic gradients
Define: Oxidative phosphorylation
When ATP formation driven by energy released from electrons removed during substrate oxidation process
Electron transport generates:
NADH and FADH2
When NADH is an electron donor, electrons enter the chain at where?
Complex 1
When FADH2 is an electron donor, electrons enter the chain at where?
Complex 2
Define: Flavoproteins
Polypeptides bound to flavin adenine dinucleotide (FAD) or flavin mononucleotide
Define: Cytochromes
Contain heme groups bearing iron or copper
5 types of electron carriers are?
- Flavoproteins
- Cytochromes
- 3 Copper atoms
- Ubiquinone
- Iron-sulfur proteins
Define: 3 Copper atoms as electron carriers
Located within single protein complex and alternate between Cu2+/Cu3+
Define: Ubiquinone
Coenzyme Q, lipid soluble molecule made of 5 carbon isoprenoid units
Define: Iron-sulfur proteins as electron carriers
Iron atoms not located within heme group, instead linked to inorganic sulfide center
How are carriers organized?
In order of increasingly positive redox potential
Electrons (lose or gain) energy as they move along the ETC?
Lose
What is the final electron acceptor of the ETC?
Oxygen
Electron carriers can be isolated as 4 complexes which are called?
Complex I, II, III, IV
Complex I function
Catalyzes transfer of pair of electrons from NADH to ubiquinone to form ubiquinol
Complex II consists of:
2 hydrophobic subunits that anchor the protein, and 2 hydrophilic subunits that comprise succinate dehydrogenase
Complex II purpose:
Provides pathway for feeding lower-energy electrons from succinate to FAD to ubiquinone
In complex II, the path from FADH2 to ubiquinone uses what?
electrons through 3 iron-sulfur clusters
Complex III purpose:
Catalyzes transfer of electrons from ubiquinol to cytochrome C
Proton releasing 2 steps in complex III
- Two protons derived from molecule of ubiquinol that entered the complex
- Two protons are removed from matrix and translocated as part of a second molecule of ubiquinol
What is the final step of the ETC?
Transfer of electrons from reduced cytochrome to oxygenn
Complex IV purpose:
Oxygen reduction catalyzed by complex IV
Complex IV consists of:
Huge assembly of subunits known as cytochrome oxidase, which is a redox-driven proton pump
For every oxygen molecule that is reduced, what happens to them?
4 are consumed to 2 molecules, and 4 are translocated to the intermembrane space
What are the two components of the Proton-motive force?
- Concentration gradient between matrix and intermembrane space creates pH gradient
- Separation of charge across membrane creates on electric potential
Proton-motive force can be used to pull what into the mitochondrion?
Calcium
Describe the structure of ATP synthase
F1 particle is catalytic subunit, contains 3 catalytic sites for ATP synthesis, and F0 particle attaches to F1 and is embedded in inner membrane
Mitochondria rely on what for energy?
Proton-motive force
Proton-motive force drive uptake of what?
ADP and Pi into mitochondria in exchange for ATP and H
