BIOCHEM 2EE3 Lecture Notes - Lecture 10: Mitochondrial Matrix, Oxidative Phosphorylation, Reduction Potential

66 views3 pages

indigohornet100

28 Apr 2018

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

-In bacteria the enzymes for pyruvate oxidation and the citric acid cycle are in the cytoplasm and

the plasma membrane

-In eukaryotes the first two stages of respiration i.e. pyruvate oxidation and the citric acid cycle

take place in the mitochondrial matrix, the third stage (electron transport and oxidative

phosphorylation) use enzymes embedded in the inner mitochondrial membrane

o Most of the enzymes of the citric acid cycle are soluble in the matrix but one is a bound

to the matrix side of the inner membrane

Carbon atoms can become oxidized in two ways

o Through the loss of a hydride ion (i.e. H-)

o Or through bonding with oxygen (oxygen’s electronegatively draws away electrons from

the carbon atom)

-Oxidation reactions are catalyzed by dehydrogenases –these enzymes remove hydrogens

(typically one hydride ion and one proton) from the substrate

Most of the energy made from cellular respiration is not from glycolysis or citric acid cycle its

from oxidative phosphorylation because NADH and FADH2 have a high redox potential –i.e.

their oxidation is highly exergonic

M10:%Readings

Monday,(April(2,(2018

11:35(AM

Unlock document

This preview shows page 1 of the document.
Unlock all 3 pages and 3 million more documents.

Already have an account? Log in

Related Questions

1.) Certain complexes of the mitochondrial electron transport chain pump protons. Which of the following BEST describes the movement of protons in this situation?

a.) across the outer mitochondrial membrane, from the cytoplasm to the intermembrane space

b.) across the outer mitochondrial membrane, from the intermembrane space to the cytoplasm

c.) across the inner mitochondrial membrane, from the intermembrane space to the matrix

d.) across the inner mitochondrial membrane, from the matrix to the inter membrane space

2.) Which regulatory mechanism is activated when the overall energy availability of a cell is high?

a.) Citrate inhibits phosphofructokinase-1.

b.) ADP up-regulates phosphofructokinase-1.

c.) ATP inhibits phosphofructokinase-1.

d.) AMP up-regulates phosphofructokinase-1.

3.) Electron carriers are oxidized during which of the following reactions?

a.) glycolysis

b.) citric acid cycle

c.) electron transport chain

d.) the conversion of pyruvate to acetyl coA

e.) all of the above

purpleswan410

Which of the following accurately describe difference(s) between oxidative phosphorylation and substrate-level phosphorylation during aerobic respiration in eukaryotes?

	a.	Oxidative phosphorylation relies on energy initially derived from redox reactions to power ATP synthase, and substrate-level phosphorylation relies on enzymatic reactions to phosphorylate ADP.
	b.	Oxidative phosphorylation takes place in the inner mitochondrial membrane and substrate-level phosphorylation only occurs in the cytosol.
	c.	Oxidative phosphorylation uses oxygen as a substrate and substrate-level phosphorylation uses phosphate.
	d.	Oxidative phosphorylation takes place during glycolysis and the electron transport chain and substrate-level phosphorylation occurs during the citric acid cycle and chemiosmosis.
	e.	Oxidative phosphorylation produces less ATP than substrate-level phosphorylation.

1. Which enzyme of the citric acid cycle catalyzes a substrate-level phosphorylation reaction?

A. Isocitrate dehydrogenase

B. Succinyl-CoA synthetase

C. Fumarase

D. Aconitase

E. Citrate synthase

2. Which enzyme of the citric acid cycle is embedded in the mitochondrial inner membrane

A. Fumurase

B. Malate dehydrogenase

C. Isocitrate dehydrogenase

D. Succinate dehydrogenase

E. Aconitase

3. The addition of Isocitrate will stimulate the TCA cycle. How many ATP can you produce from one molecule of Isocitrate?

A. 10

B. 7.5

C. 4

D. 5

4. In the reaction mechanism for the oxidative decarboxylation of pyruvate, which cofactor is required for the decarboxylation step?

A. Thiamine pyrophosphate

B. Lipoic acid

C. FAD

D. NAD+

E. all of the above

BIOCHEM 2EE3 Lecture Notes - Lecture 10: Mitochondrial Matrix, Oxidative Phosphorylation, Reduction Potential

Get access

Related Documents

BIOCHEM 2EE3 Lecture Notes - Lecture 12: Allosteric Regulation, Fatty Acid Metabolism, Carboxylation

BIOCHEM 2EE3 Lecture Notes - Lecture 10: Allosteric Regulation, Enzyme Inhibitor, Catabolism

BIOCHEM 2EE3 Lecture Notes - Lecture 10: Catabolism, Oxaloacetic Acid, Chlorophyll

Related Questions