Murphy Biochem Rutgers Exam 2

Place the following reaction intermediates of the CAC in chronological order

i. malate ii. fumarate iii. succinyl CoA iv. citrate v. a-ketoglutarate

iv, v, iii, ii, i

Oxalosuccinate is a transient intermediate formed during which of the following reactions?

isocitrate to a-ketoglutarate

FADH2 is a product of which of the following reactions?

succinate to fumarate

NADH is produced in which of the following reactions?

a-ketoglutarate to succinyl CoA

Which of the following reactions can be described as anaplerotic?

pyruvate + co2 to oxaloacetate

The enzymes that are unique to the glyoxylate cycle include ____________

isocitrate lyase

The regulated enzyme of the CAC include _________

a-ketoglutarate dehydrogenase

The enzymes involved in citrate metabolism include all of the following except ________

malate synthase

Redox potential is best defined as

the tendency of a species to gain or lose electrons

In order to determine the standard voltage of a reaction

the standard cells must be written as they occur in the reaction and the voltages are added

Which of the following reactions is an oxidation reaction?

a. NaOH + HCl -> NaCl + H2O

b. CH3COOH -> CH3COO- + H+

c. CH3CHO -> CH3CH2OH

d. CH3CH2OH -> CH3CHO

e. CH2=CH2 + H2O -> CH3CH2OH

CH3CH2OH -> CH3CHO

Which of the following reactions has an oxidized product?

a. carboxylic acid -> aldehyde

b. R-SH + R-SH -> R-S-S-R

c. alcohol -> ketone

d. glutamate -> a-ketoglutarate

e. none of the above

none of the above

In any redox reaction, an electron donor is

the reducing agent

In an redox reaction, an electron acceptor is

converted to an electron donor with the gain of one or more electrons

Each turn of the CAC produces how many moles of CO2?

2

Acetyl CoA that is consumed by the CAC is produced from which of the following biochemical pathways?

a. glycolysis

b. fatty acid oxidation

c. purine catabolism

d. urea cycle

e. both A and B are correct

both A and B are correct

Which of the following is the strongest reducing agent?

a. FADH2 (+ 0.22 V)

b. H2 (+ 0.424 V)

c. cytochrome a * Fe 2+ (-0.29 V)

d. lactate (+0.19 V)

e. H2O (-0.82 V)

H2

Which of the following reacts with the acetyl-CoA to form citrate?

oxaloacetate

The redox reaction in which succinate is converted to fumarate uses FAD rather than NAD+ because?

FAD is a stronger oxidizing agent than NAD+

Which of the following CAC enzymes are closely regulated?

a. citrate synthase

b. isocitrate dehydrogenase

c. a-ketoglutarate dehydrogenase

d. both A and B are correct

e. A, B, and C are all correct

A, B, and C are all correct

Which of the following requires GDP?

succinyl-CoA to succinate

How many oxidation steps are there in the CAC?

4

Which of the following is a cofactor for the conversion of succinate to fumarate?

FAD

Which of the following reactions involves a substrate level phosphorylation?

succinyl-CoA to succinate

The carbon skeletons of which of the following can be incorporated directly into the protein?

a. malate

b. succinate

c. a-ketoglutarate

d. oxaloacetate

e. both C and D are correct

both C and D are correct

Which of the following is a positive effector of isocitrate dehydrogenase?

ADP

Which of the following is not directly required for the activity of pyruvate dehydrogenase?

ATP

The overall reaction catalyzed by pyruvate dehydrogenase is which of the following?

a. CH3COCHO + NAD+ + CoASH -> CH3CHOSCoA + NADH

b. CH3COCOO- + FAD + CoASH -> CH3COSCoA + FADH2

c. CH3COCOO- + NAD+ + CoASH -> CH3COSCoA + NADH

d. CH3CH(OH)COO- + NADH + CoASH -> CH3CH(OH)COSCoA + NAD+

e. None of the above are correct

...what kind of fresh hell is this

c. CH3COCOO- + NAD+ + CoASH -> CH3COSCoA + NADH

The CAC is a component of metabolic respiration, i.e, molecular oxygen is...

only indirectly involved in the reactions of the cycle

The reaction process catalyzed by pyruvate dehydrogenase requires all of the following except ______

FMN

All of the following are components of the electron transport chain except ____________

Coenzyme A

The ETC component that transfers electrons directly to oxygen is _________

cytochrome oxidase

During the oxidation of NADH there are several steps in which DEo' is sufficient for ATP synthesis. These occur with in complexes...

I, III, and IV

Which of the following molecules inhibits Complex I of the electron transport chain?

Amytal

ATP synthesis and mitochondrial electron transport are coupled by

a. protonmotive force

b. high energy intermediates

c. proton gradient

d. Both A and C are correct

e. A, B, and C are correct

d. Both A and C are correct

Evidence supporting the chemiosmotic theory includes all of the following except

the pH of a weakly buffered suspension of mitochondria rises when O2 is added

Examples of uncouplers include (there are 2)

DNP and gramicidin

In the ATP Synthase the F0 factor

a. has 3 types of subunits

b. possesses the ATPase activity

c. is a transmembrane proton channel

d. Both A and B are correct

e. Both A and C are correct

e. Both A and C are correct

The maximum P/O ratio for FADH2 is ____________

1.5

The control of aerobic respiration by ______________________________ is referred to as respiratory control

ADP

The first ROS formed during the reduction of oxygen is ______________

superoxide radical

The reaction of Fe2+ with H2O2 results in the production of

a. hydroxyl radical

b. hydroxide ion

c. superoxide radical

d. Both A and B are correct

e. Both A and C are correct

d. Both A and B are correct

ROS are generated during

a. xenobiotic metabolism

b. respiratory burst

c. ionizing radiation

d. Both A and B are correct

e. A, B, and C are correct

e. A, B, and C are correct

Glutathione peroxidase

a. converts organic peroxides into alcohols

b. generates GSH from GSSG

c. reduces H2O2 to H2O

d. Both A and B are correct

e. Both A and C are correct

e. Both A and C are correct

The NADPH required for the regeneration of GSH from GSSG is synthesized by the reactions of

the pentose phosphate pathway

Glutathione peroxidase requires _____________ for full activity

selenium

Examples of antioxidants include all of the following except

a. ascorbic acid

b. b-Carotene

c. a-Tocopherol

d. phenol

e. gramicidin

e. gramicidin

One of the mechanisms by which vitamin C protects membrane is by

a. regenerating reduced a-tocopherol

b. reacting with proline

c. reacting with peroxyl radicals

d. Both A and B are correct

e. Both A and C are correct

e. Both A and C are correct

The ultimate electron acceptor of the mitochondrial electron transport system is

O2

In complex I of the ETC, the major sources of NADH include

a. fatty acid oxidation

b. CoQ

c. NADPH

d. the citric acid cycle

e. Both A and D are correct

e. Both A and D are correct

In complex III, electrons are transferred from UQH2 to

cytochrome c

_______ is a metal cofactor of the cytochromes

Fe

Carbon monoxide inhibits which of the following?

cytochrome oxidase

Which of the following is the best reducing agent?

a. H2O

b. O2

c. FADH2

d. FMNH2

e. NADH

e. NADH

The final product of oxidative phosphorylation is?

ATP

________________ are hydrophobic molecules that dissipate ion gradients

ionophores

The return of _______ into the mitochondrion is coupled to the formation of _______

H+; ATP

The energy that is captured by the electron transport system and used in oxidative phosphorylation is in the form of

a. NADH

b. FADH2

c. ATP

d. Both A and B are correct

e. A, B, and C are correct

d. Both A and B are correct

Reducing power generated in the cytoplasm can be transferred into the mitochondrion by which of the following processes?

a. glycerol phosphate shuttle

b.malate-aspartate shuttle

c. the phosphate shuttle

d. Both A and B are correct

e. A, B, and C are correct

d. Both A and B are correct

Fatty acid groups are referred to as ________ groups.

acyl

The double bonds in naturally occurring fatty acids are usually ______ isomers

cis

The essential fatty acids are

a. arachidonic acid

b. linoleic acid

c. linolenic acid

d. Both A and B are correct

e. Both B and C are correct

what the **** lmao

e. Both B and C are correct

Fatty acids react with alcohols to form?

esters

Prostaglandins are involved in?

a. ovulation

b. inflammation

c. digestion

d. Both A and B are correct

e. A, B, and C are correct

d. Both A and B are correct

The functions of fat include:

a. insulation

b. energy storage

c. water-repellent properties

d. Both A and B are correct

e. A, B, and C are correct

e. A, B, and C are correct

Waxes

a. are complex mixtures of nonpolar lipids

b. are esters formed from long-chain fatty acids and long-chain alcohols

c. contain hydrocarbons, sterols, and alcohols

d. Both A and B are correct

e. Both A and C are correct

e. Both A and C are correct

Phospholipids are

a. structural components of membranes

b. surface active agents

c. rich energy sources

d. Both A and B are correct

e. A, B, and C are correct

d. Both A and B are correct

Phosphatidylcholine is sometimes referred to as

a. PIP2

b. cephalin

c. ceramide

d. cardiolipin

e. none of the above

e. none of the above

The myelin sheath

a. surrounds nerve cell axons

b. contains large amounts of cardiolipin

c. facilitates nerve impulse transmission

d. Both A and B are correct

e. Both A and C are correct

e. Both A and C are correct

All of the following are glycolipids except ____________

a. sulfatides

c. cerebrosides

c. gangliosides

d. Both A and B are correct

e. none of the above

e. none of the above

The role of very low density lipoproteins is

a. scavenging the cholesterol from cell membranes

b. transporting of lipids from liver to tissue

c. transporting of cholesterol from esters to the liver

d. Both A and B are correct

e. A, B, and C are correct

b. transporting of lipids from liver to tissue

Which of the following statements concerning carotenoids is not true?

a. carotenoids are the only examples of the monoterpenes

b. the carotenes are hydrocarbon members of the carotenoids

c. xanthophylls are oxygenated derivatives of the carotenes

d. carotenes are orange-colored pigments

e. none of the above

a. carotenoids are the only examples of the monoterpenes

Which of the following statements concerning coronary artery disease is not true?

a. coronary artery disease is one of the most common consequences of atherosclerosis

b. high plasma LDL levels are correlated with high risk for coronary artery disease

c. cells destined to become "foam cells" in the lining of the blood vessels possesses LDL receptors

d. the macrophages found within atherosclerotic plaque possesses LDL receptors with an affinity for oxidized LDL

e. none of the above

e. none of the above

The basic structure of biological membranes is a consequence of _____________

phospholipids

A membrane's fluidity is largely determined by the percentage of

unsaturated fatty acids

In the fluid mosaic model of membrane structure

proteins float in a lipid bilayer

Which of the following statements concerning anion channel proteins is not true?

a. it plays an important role in CO2 transport in blood

b. it facilitates the chloride shift

c. HCO3- and Cl- exchange occurs through the anion channel protein

d. the N-terminal methionine residue of the anion channel protein is prenylated

e. none of the above

d. the N-terminal methionine residue of the anion channel protein is prenylated

Energy-requiring transport mechanisms include?

primary active transport

In simple diffusion a solute...

is propelled by random molecular motion

Which of the following statements is not true?

a. membrane potential is an electrical gradient across a membrane

b. a decrease in membrane potential is referred to as membrane depolarization

c. the term repolarization is defined as the reestablishment of the original membrane potential

d.the diffusion of K+ ions out of a nerve cell makers the inside of the membrane less negative

e. the Na+ channel in muscle and nerve cells is a voltage-gated channel

d. the diffusion of K+ ions out of a nerve cell makes the inside of the membrane less negative

In muscle cells, local depolarization caused by acetylcholine binding leads to the opening of the voltage-gated _____channels.

a. Cl-

b. K+

c. H+

d. Na+

e. glucose permease

d. Na+

The function of glucose permease is an example of

secondary active transport

The glucose permease is an example of a/an ______________

symporter

Membrane receptors are transmembrane molecules or molecular complexes that..

a. monitor and respond to changes in the cell's environment

b. bind to hormones or neurotransmitters

c. are involved in embryonic and fetal development

d. initiate an intracellular response when they bind an appropriate muscle

e. all of the above

e. al of the above

Patients with familial hypercholesterolemia

develop xanthomas

_______________ is a technique used to investigate lateral diffusion of membrane components

fluorescence recovery after photobleaching

Bacterorhodopsin of the purple membrane of Halobacterium...

a. acts as a light-driven Cl- channel

b. is the sole protein component of purple membrane

c. is formed under conditions of low O2 concentration and high lit intensity

d. Both A and B are correct

e. Both B and C are correct

e. Both B and C are correct

Rbc membrane is useful in membrane research because it is

a. obtainable in large amounts from blood banks

b. easily purified

c. easily separated from intracellular membrane

d. Both A and B are correct

e. A, B, and C are correct

d. Both A and B are correct

Nephrogenic diabetes insipidis is...

a. a rare genetic disease

b. caused by a mutated water channel

c. a malady in which affected individuals produce excessively concentrated urine

d. Both A and B are correct

e. A, B, and C are correct

e. A, B, and C are correct

In plants triacylglycerols are stored in ___________

oil bodies

_____________ is used to transport fatty acids into the mitochondria

carnitine

The b-oxidation of fatty acids requires...?

a. coenzyme A

b. FAD

c. NAD+

d. Both A and C are correct

e. A, B, and C are correct

e. A, B, and C are correct

_____________, a product of the oxidation of odd-chain fatty acids, is converted to succinyl-CoA

propionyl-CoA

________________ derive a substantial amount of energy from the oxidation of odd-chain fatty acids

ruminants

The carbon atoms of cholesterol are derived from?

acetyl CoA

In animals the function of peroxisomal b-oxidation appears to be to

shorten very long chain fatty acids

The acetyl-CoA derived from gylyoxysomal b-oxidation is converted to carbohydrate via

a. the glyoxylate cycle

b. the citric acid cycle

c. gluconeogensis

d. Both A and B are correct

e. Both A and C are correct

e. Both A and C are correct

Refsum's disease results from a buildup of ________ in nerve tissue

phytanic acids

Which of the following is not one of the ketone bodies?

a. acetoacetate

b. b-Hydroxybutyrate

c. b-Methylgiutarate

d. acetone

e. none of the above

c. b-Methylgiutarate

Most eicosanoids are derived from ________ acid.

arachidonic