Lecture 33 ETC and Oxidative Phosphorylation

Oxidative phosphorylation and the TCA cycle take place in the ____________

mitochondria

____ has to be regenerated for glycolysis.

NAD+

_______ links the TCA cycle and glycolysis

Citrate

The goal of the TCA cycle is to _______ _________ in the form of NADH and FADH2.

harness electrons

The TCA cycle is regulated by the ratio of ____ to ____

NADH; NAD+

Glycolysis takes place in the _________

cytoplasm

Most the the ATP produced in the mitochondrial matric is used in the _______

cytosol

Electrons drive a ________ ________ which flows through ATP synthase and makes ATP.

hydrogen gradient

____ _________ of fatty acids takes place in the mitochondria.

Beta oxidation

_____ ____ catabolism takes place in the mitochondria.

Amino acid

Part of the ____ cycle takes place in the mitochondria.

urea

The inner mitochondrial membrane contains _ _________ that reduce NADH to NAD+ and shuttle electrons using heme proteins. This pumps ________ ____ into the intermembrane space.

4 complexes; hydrogen ions

_________ and ________ are in complex 2 in the inner mitochondrial membrane and are directly linked to the ___ cycle.

Succinate; fumarate; TCA

There is a _____ energy difference from the start to end of the ETC, so complexes must take a small amount of energy at a time.

large

________ or ______ inhibits complex 1, _________ _ inhibits complex 3, and _______ inhibits complex 4.

Rotenone; amytal; antimycin A; cyanide

Cytochromes in the ETC use ____ groups to transfer energy.

heme

High levels of hydrogen ions flow through ___ _______ to make ATP.

ATP synthase

Glycolytically produced cytosolic NADH must be able to access electron transport for _______ _________ in the mitochondria.

aerobic oxidation

Mitochondrially produced ATP must reach the _______ and ADP and Pi as oxidative phosphorylation substrates must enter the _____________

cytosol; mitochondrion

______ have alot of _____ fat which more heat is produced because of uncoupling. Some of the energy that would be used to build the hydrogen ion gradient is lost in the form of heat.

Babies; brown

___-_____________ (___) binds to hydrogen ions built up in gradient and diffuse across the inner mitochondrial membrane (low pH) which produces heat.

2,4-Dinitrophenol (DNP)

Citrate regulates both glycolysis and the ___ _____ by feeding back to _______ ________.

TCA cycle; citrate synthase

Glycolysis is _________ and produces _ ATP via substrate-level phosphorylation.

anaerobic; 2

The ETC is _______ and produces __ ATP via oxidative phosphorylation.

aerobic; 32

All organisms do not use aerobic respiration because lack of oxygen can cause ________ _______ and the _____ and _____ rely heavily on aerobic metabolism of glucose.

ischemic effects; heart; brain

________ ______ _______ (___) can be produced during aerobic respiration as O2 is sometimes partially reduced.

Reactive oxygen species (ROS)

____________ and ___________ can help to neutralize free radicals using ___________ mechanisms. Free radicals can cause damage to ___ and _________ which is one theory as to why we age.

Mitochondria; peroxisomes; antioxidant; DNA; membranes

______ _______ is produced in the TCA cycle.

Carbon dioxide

Pyruvate (2 carbons) is a precursor to ______ ___ in the TCA cycle which combines with ____________ to produce citrate (6 carbons).

Acetyl CoA; oxaloacetate

____ is a byproduct of amino acid breakdown.

Urea

When the ____/____ ratio is HIGH, glycolysis and the TCA cycle are _________ because of the excess of electrons.

NADH/NAD+; inhibited

T/F: The last step in aerobic catabolism is oxidative phosphorylation.

True

What is the consequence of uncoupling mitochondrial oxidative phosphorylation?

It increases O2 consumption, but blocks mitochondrial ATP formation.

__________ means that the hydrogen ion gradient is still being formed, but the gradient is being dissipated or blocked meaning ATP cannot be made. Oxygen is still being used as an electron acceptor.

Uncoupling