Question 1

In the liver, ammonia is converted to for eventual elimination in the urine.

Accepted Answer

A) ketones 
B) bile 
C) lactic acid 
D) bilirubin 
E) urea 
A) ketones 
B) bile 
C) lactic acid 
D) bilirubin 
E) urea E

Question 2

How do enzymes speed up chemical reactions?

Accepted Answer

A) by lowering the temperature, thereby reducing friction 
B) by making sure the enzyme is part of the product 
C) by lowering the activation energy barrier 
D) by converting kinetic energy back to potential energy 
E) by increasing the activation energy barrier 
A) by lowering the temperature, thereby reducing friction 
B) by making sure the enzyme is part of the product 
C) by lowering the activation energy barrier 
D) by converting kinetic energy back to potential energy 
E) by increasing the activation energy barrier C

Question 3

In skeletal muscle, ATP can be synthesized by transferring a phosphate group from creatine- P to ADP to form ATP and creatine. In this example, ATP was synthesized by what process?

Accepted Answer

A) oxidation 
B) substrate- level phosphorylation 
C) reduction 
D) oxidative phosphorylation 
E) condensation 
A) oxidation 
B) substrate- level phosphorylation 
C) reduction 
D) oxidative phosphorylation 
E) condensation B

Question 4

During end- product inhibition, the final product in a metabolic pathway (allosterically / covalently)regulates the activity of an enzyme earlier in the pathway.

Accepted Answer

The answer of During end- product inhibition, the final product...

Question 5

Cyanide is a deadly poison that attaches to cytochrome c oxidase, the last protein in the electron transport chain before the terminal electron acceptor. Based on your knowledge of the electron transport chain, which statement below best describes the action of cyanide on the body?

Accepted Answer

A) Cyanide blocks the terminal electron acceptor oxygen and therefore will halt the production of ATP. The majority of ATP is normally produced in the electron transport chain and without it the body will begin to only go through glycolysis and start producing lactic acid and will eventually shut down due to a lack of ATP to run the body and because of the buildup of acid in the system. 
B) Cyanide does not allow the Krebs cycle to be completed by blocking acetyl CoA from entering this cycle. This action shuts down the entire process of cellular metabolism. 
C) Cyanide blocks the terminal electron acceptor, oxygen, causing an accumulation of CO2 in the tissues from cellular metabolism, and poisons the system due to excess waste products. 
D) Cyanide does not allow H+ ions to be pumped into the outer membrane of the mitochondria and, therefore, they are never able to go down their concentration gradient and produce ATP. 
E) Cyanide prevents NADH and FADH2 from dropping off their electrons at the beginning of the electron transport chain by causing a backup of electrons in the Krebs cycle. 
A) Cyanide blocks the terminal electron acceptor oxygen and therefore will halt the production of ATP. The majority of ATP is normally produced in the electron transport chain and without it the body will begin to only go through glycolysis and start producing lactic acid and will eventually shut down due to a lack of ATP to run the body and because of the buildup of acid in the system. 
B) Cyanide does not allow the Krebs cycle to be completed by blocking acetyl CoA from entering this cycle. This action shuts down the entire process of cellular metabolism. 
C) Cyanide blocks the terminal electron acceptor, oxygen, causing an accumulation of CO2 in the tissues from cellular metabolism, and poisons the system due to excess waste products. 
D) Cyanide does not allow H+ ions to be pumped into the outer membrane of the mitochondria and, therefore, they are never able to go down their concentration gradient and produce ATP. 
E) Cyanide prevents NADH and FADH2 from dropping off their electrons at the beginning of the electron transport chain by causing a backup of electrons in the Krebs cycle.

Question 6

What is the most important energy- transferring compound in cells?

Accepted Answer

A) fructose 
B) glucose 
C) deoxyribonucleic acid 
D) protein 
E) adenosine triphosphate 
A) fructose 
B) glucose 
C) deoxyribonucleic acid 
D) protein 
E) adenosine triphosphate

Question 7

What process occurs within the inner mitochondrial membrane?

Accepted Answer

A) gluconeogenesis 
B) glycogenesis 
C) glycolysis 
D) electron transport chain 
E) Krebs cycle 
A) gluconeogenesis 
B) glycogenesis 
C) glycolysis 
D) electron transport chain 
E) Krebs cycle

Question 8

In allosteric regulation, the modulator molecule binds to the

Accepted Answer

A) cofactor by weak, reversible interactions. 
B) catalytic site of the enzyme by weak, reversible interactions. 
C) regulatory site of the enzyme by weak, reversible interactions. 
D) regulatory site by covalent bonds. 
E) catalytic site by covalent bonds. 
A) cofactor by weak, reversible interactions. 
B) catalytic site of the enzyme by weak, reversible interactions. 
C) regulatory site of the enzyme by weak, reversible interactions. 
D) regulatory site by covalent bonds. 
E) catalytic site by covalent bonds.

Question 9

Potential energy describes the energy possessed by an object in motion.

Accepted Answer

A) True 
 B)False

Question 10

In a metabolic pathway, both help to keep reaction rates within normal ranges by either speeding them up or slowing them down.

Accepted Answer

A) feedforward activation and feedback inhibition 
B) lock- in- key and induced- fit models 
C) coenzymes and cofactors 
D) affinity and substrate concentration 
E) ligand and protein interactions 
A) feedforward activation and feedback inhibition 
B) lock- in- key and induced- fit models 
C) coenzymes and cofactors 
D) affinity and substrate concentration 
E) ligand and protein interactions

Question 11

The sum of the thousands of chemical reactions that occur within the body is called

Accepted Answer

A) hydrolysis. 
B) oxidation. 
C) reduction. 
D) phosphorylation. 
E) metabolism. 
A) hydrolysis. 
B) oxidation. 
C) reduction. 
D) phosphorylation. 
E) metabolism.

Question 12

A=B + 2H -HA-BH is an example of what type of reaction?

Accepted Answer

A) hydrolysis 
B) condensation 
C) oxidation 
D) reduction 
E) phosphorylation 
A) hydrolysis 
B) condensation 
C) oxidation 
D) reduction 
E) phosphorylation

Question 13

Where does beta- oxidation of fatty acids occur?

Accepted Answer

A) peroxisome 
B) mitochondrial intermembrane space 
C) smooth endoplasmic reticulum 
D) mitochondrial matrix 
E) cytosol 
A) peroxisome 
B) mitochondrial intermembrane space 
C) smooth endoplasmic reticulum 
D) mitochondrial matrix 
E) cytosol

Question 14

During what type of reaction are electrons removed from the reactant?

Accepted Answer

A) reduction 
B) oxidation 
C) phosphorylation 
D) electrocution 
E) None of the answers is correct. 
A) reduction 
B) oxidation 
C) phosphorylation 
D) electrocution 
E) None of the answers is correct.

Question 15

According to the induced- fit model for enzymes, the binding of substrate to the active site alters the structure of the enzyme.

Accepted Answer

A) True 
 B)False

Question 16

What is the first component of the electron transport chain that accepts electrons from an NADH molecule?

Accepted Answer

A) coenzyme Q 
B) cytochrome a3 
C) cytochrome b 
D) flavin mononucleotide 
E) flavin adenine dinucleotide 
A) coenzyme Q 
B) cytochrome a3 
C) cytochrome b 
D) flavin mononucleotide 
E) flavin adenine dinucleotide

Question 17

Not all enzymes have substrate specificity. For example, pepsin can breakdown numerous types of proteins in the stomach. What concept best describes why the single enzyme pepsin can breakdown so many proteins?

Accepted Answer

A) the law of mass action 
B) ligand- protein interactions 
C) the induced- fit model 
D) complementary base pairing rule 
E) the lock- and- key model 
A) the law of mass action 
B) ligand- protein interactions 
C) the induced- fit model 
D) complementary base pairing rule 
E) the lock- and- key model

Question 18

Enzymes increase the activation energy of a reaction.

Accepted Answer

A) True 
 B)False

Question 19

Binding of a modulator to a regulatory site alters the structure of the enzyme in a way that can affect catalytic rate and/or affinity.

Accepted Answer

A) True 
 B)False

Question 20

With the plethora of enzymes that are present within each cell, the activity of each enzyme must be carefully regulated. Describe the two ways that enzyme reactions are regulated within the body and give examples of each.

Accepted Answer

Reaction rates of enzymes are continuous

Exam 3: Cell Metabolism

In the liver, ammonia is converted to for eventual elimination in the urine.

How do enzymes speed up chemical reactions?

In skeletal muscle, ATP can be synthesized by transferring a phosphate group from creatine- P to ADP to form ATP and creatine. In this example, ATP was synthesized by what process?

During end- product inhibition, the final product in a metabolic pathway (allosterically / covalently)regulates the activity of an enzyme earlier in the pathway.

Cyanide is a deadly poison that attaches to cytochrome c oxidase, the last protein in the electron transport chain before the terminal electron acceptor. Based on your knowledge of the electron transport chain, which statement below best describes the action of cyanide on the body?

What is the most important energy- transferring compound in cells?

What process occurs within the inner mitochondrial membrane?

In allosteric regulation, the modulator molecule binds to the

Potential energy describes the energy possessed by an object in motion.

In a metabolic pathway, both help to keep reaction rates within normal ranges by either speeding them up or slowing them down.

The sum of the thousands of chemical reactions that occur within the body is called

A=B + 2H -HA-BH is an example of what type of reaction?

Where does beta- oxidation of fatty acids occur?

During what type of reaction are electrons removed from the reactant?

According to the induced- fit model for enzymes, the binding of substrate to the active site alters the structure of the enzyme.

What is the first component of the electron transport chain that accepts electrons from an NADH molecule?

Not all enzymes have substrate specificity. For example, pepsin can breakdown numerous types of proteins in the stomach. What concept best describes why the single enzyme pepsin can breakdown so many proteins?

Enzymes increase the activation energy of a reaction.

Binding of a modulator to a regulatory site alters the structure of the enzyme in a way that can affect catalytic rate and/or affinity.

With the plethora of enzymes that are present within each cell, the activity of each enzyme must be carefully regulated. Describe the two ways that enzyme reactions are regulated within the body and give examples of each.

Introduction to Physiology

The Cell: Structure and Function

Cell Membrane Transport

Chemical Messengers

The Endocrine System: Endocrine Glands and Hormone Actions

Nerve Cells and Electrical Signaling

Synaptic Transmission and Neural Integration

The Nervous System: Central Nervous System

The Nervous System: Sensory Systems

The Nervous System: Autonomic and Motor Systems

Muscle Physiology

The Cardiovascular System: Cardiac Function

The Cardiovascular System: Blood Vessels, Blood Flow, and Blood Pressure

The Cardiovascular System: Blood

The Respiratory System: Pulmonary Ventilation

The Respiratory System: Gas Exchange and the Regulation of Breathing

The Urinary System: Renal Function

The Urinary System: Fluid and Electrolyte Balance

The Gastrointestinal System

The Endocrine System: Regulation of Energy Metabolism and Growth

The Reproductive System

The Immune System

Diabetes Mellitus

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