BIC09L_ Enzymology I & II

Created by _fivedan

p.9

What happens to the overall free energy change (ΔG) when an enzyme is used in a reaction?

A. It remains unchanged

B. It becomes negative

C. It increases

D. It decreases

E. It becomes positive

Select an answer

p.9

Explanation

Enzymes do not affect the overall free energy change (ΔG) of a reaction; they only change the reaction pathway and lower the activation energy required for the reaction to proceed.

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p.9

Enzyme Activation and Regulation

What happens to the overall free energy change (ΔG) when an enzyme is used in a reaction?

p.1

Characteristics and Actions of Enzymes

What is one of the key characteristics of enzymes?

p.1

Mechanisms of Enzyme Inhibition and Activation

What is a common mechanism of enzyme inhibition?

p.1

Role of Enzymes in Diagnosis and Therapy

How do enzymes play a role in diagnosis and therapy?

p.21

Enzyme Activation and Regulation

What is a zymogen?

p.2

Characteristics and Actions of Enzymes

What is the primary function of enzymes?

p.2

Characteristics and Actions of Enzymes

Where are enzymes primarily located in the body?

p.2

Classes of Enzymes

What type of enzymes work inside cells?

p.2

Classes of Enzymes

Which of the following is an example of an exoenzyme?

p.2

Role of Enzymes in Diagnosis and Therapy

What percentage of the human genome encodes for enzymes?

p.3

Structure of Enzymes

What is the primary function of the active site of an enzyme?

p.3

Structure of Enzymes

Which level of protein structure refers to the overall 3D shape of the enzyme?

p.3

Structure of Enzymes

What are cofactors and coenzymes in relation to enzyme function?

p.3

Structure of Enzymes

What is the significance of the amino acid sequence in enzyme structure?

p.3

Structure of Enzymes

What is the role of the catalytic site within the active site of an enzyme?

p.4

Characteristics and Actions of Enzymes

What is a key characteristic of enzymes regarding their function in chemical reactions?

p.4

Characteristics and Actions of Enzymes

How do enzymes demonstrate specificity?

p.4

Effects of pH and Temperature on Enzyme Activity

What factors can affect enzyme activity?

p.4

Characteristics and Actions of Enzymes

What does it mean for enzymes to be reusable?

p.4

Enzyme Activation and Regulation

What is allosteric regulation in enzymes?

p.5

Classes of Enzymes

What type of reactions do oxidoreductases catalyze?

p.5

Classes of Enzymes

Which class of enzymes is responsible for transferring functional groups between molecules?

p.5

Classes of Enzymes

What do hydrolases catalyze?

p.5

Classes of Enzymes

Which class of enzymes catalyzes intramolecular rearrangements?

p.5

Classes of Enzymes

What is the function of ligases?

p.6

Mechanisms of Enzyme Inhibition and Activation

What is the first step in the mechanism of enzyme reaction?

p.6

Mechanisms of Enzyme Inhibition and Activation

What occurs during the formation of the enzyme-substrate complex?

p.6

Mechanisms of Enzyme Inhibition and Activation

What is the role of the enzyme in the transition state formation?

p.6

Mechanisms of Enzyme Inhibition and Activation

What happens to the enzyme after the product is released?

p.6

Mechanisms of Enzyme Inhibition and Activation

Which of the following describes the process of catalysis in enzyme reactions?

p.7

Mechanisms of Enzyme Inhibition and Activation

What does the 'Lock and Key' model of enzyme-substrate binding suggest?

p.7

Mechanisms of Enzyme Inhibition and Activation

Who proposed the 'Induced-fit' model of enzyme-substrate binding?

p.7

Mechanisms of Enzyme Inhibition and Activation

What is a key difference between the 'Lock and Key' model and the 'Induced-fit' model?

p.7

Mechanisms of Enzyme Inhibition and Activation

What year was the 'Lock and Key' model proposed?

p.7

Mechanisms of Enzyme Inhibition and Activation

What does the 'Induced-fit' model imply about the structure of enzymes?

p.8

Enzyme Activation and Regulation

What is the role of the active site in enzyme-substrate complex formation?

p.8

Mechanisms of Enzyme Inhibition and Activation

What happens during the 'induced fit' of an enzyme?

p.8

Characteristics and Actions of Enzymes

What is a key characteristic of enzymes regarding substrate binding?

p.8

Enzyme Kinetics and Michaelis-Menten Model

What occurs after the enzyme-substrate complex is formed?

p.8

Role of Enzymes in Diagnosis and Therapy

What does the reaction representation E + S → ES → E + P indicate?

p.9

Enzyme Activation and Regulation

What is the transition state in a chemical reaction?

p.9

Enzyme Activation and Regulation

How do enzymes affect the activation energy of a reaction?

p.9

Enzyme Activation and Regulation

What does ΔG represent in a chemical reaction?

p.9

Enzyme Activation and Regulation

What is the significance of understanding the transition state in drug design?

p.10

Enzyme Kinetics and Michaelis-Menten Model

What does enzyme kinetics study?

p.10

Enzyme Kinetics and Michaelis-Menten Model

What is the reaction rate (v) in enzyme kinetics?

p.10

Enzyme Kinetics and Michaelis-Menten Model

How does substrate concentration affect enzyme activity?

p.10

Effects of pH and Temperature on Enzyme Activity

What is indicated by the peak of the bell-shaped curve in the enzyme activity vs. temperature graph?

p.10

Mechanisms of Enzyme Inhibition and Activation

What does the presence of a competitive inhibitor do to the reaction rate?

p.11

Effects of pH and Temperature on Enzyme Activity

What is the optimal pH for Pepsin?

p.11

Effects of pH and Temperature on Enzyme Activity

At what temperature do most human enzymes exhibit optimal activity?

p.11

Effects of pH and Temperature on Enzyme Activity

What happens to enzyme activity if the pH is too high or too low?

p.11

Effects of pH and Temperature on Enzyme Activity

Which enzyme has an optimal pH of around 7?

p.11

Effects of pH and Temperature on Enzyme Activity

What occurs to enzyme activity as temperature rises above the optimal level?

p.12

Enzyme Kinetics and Michaelis-Menten Model

What happens to the reaction rate when enzyme concentration increases while substrate is in excess?

p.12

Enzyme Kinetics and Michaelis-Menten Model

At which point does the reaction rate become independent of substrate concentration?

p.12

Enzyme Kinetics and Michaelis-Menten Model

What is the relationship between substrate concentration and reaction rate at low substrate levels?

p.12

Enzyme Kinetics and Michaelis-Menten Model

What occurs as substrate concentration increases beyond a certain point?

p.12

Enzyme Kinetics and Michaelis-Menten Model

What is indicated by the graph showing the relationship between substrate concentration and rate of reaction?

p.13

Enzyme Kinetics and Michaelis-Menten Model

What does the Michaelis-Menten model describe?

p.13

Enzyme Kinetics and Michaelis-Menten Model

What happens to the reaction velocity as substrate concentration increases according to the Michaelis-Menten model?

p.13

Enzyme Kinetics and Michaelis-Menten Model

What does Vmax represent in the Michaelis-Menten model?

p.13

Enzyme Kinetics and Michaelis-Menten Model

What does a low Km value indicate about an enzyme's affinity for its substrate?

p.13

Enzyme Kinetics and Michaelis-Menten Model

Who proposed the Michaelis-Menten model?

p.14

Enzyme Kinetics and Michaelis-Menten Model

What does the Lineweaver-Burk plot help to analyze?

p.14

Enzyme Kinetics and Michaelis-Menten Model

In the Lineweaver-Burk plot, what does the Y-intercept represent?

p.14

Enzyme Kinetics and Michaelis-Menten Model

What is the relationship between the slope of the Lineweaver-Burk plot and enzyme constants?

p.14

Enzyme Kinetics and Michaelis-Menten Model

What does the X-intercept of the Lineweaver-Burk plot indicate?

p.14

Enzyme Kinetics and Michaelis-Menten Model

What is the primary purpose of linearizing the Michaelis-Menten equation in the Lineweaver-Burk plot?

p.15

Enzyme Kinetics and Michaelis-Menten Model

What is the primary purpose of the Michaelis-Menten model in enzyme kinetics?

p.15

Enzyme Kinetics and Michaelis-Menten Model

What does the term 'catalytic efficiency' refer to in the context of enzyme activity?

p.15

Enzyme Kinetics and Michaelis-Menten Model

What does the turnover number (Kcat) indicate about an enzyme?

p.15

Enzyme Kinetics and Michaelis-Menten Model

What does Km represent in enzyme kinetics?

p.15

Enzyme Kinetics and Michaelis-Menten Model

Which equation relates Vmax, Kcat, and total enzyme concentration?

p.16

Enzyme Kinetics and Michaelis-Menten Model

What is the physiological significance of enzymes with a Km near the physiological substrate concentration?

p.16

Enzyme Kinetics and Michaelis-Menten Model

What characterizes enzymes with a very low Km?

p.16

Enzyme Kinetics and Michaelis-Menten Model

How do enzymes with a very high Km function in relation to substrate levels?

p.16

Enzyme Kinetics and Michaelis-Menten Model

What is the Km value for hexokinase in most tissues, and what does it indicate?

p.16

Enzyme Kinetics and Michaelis-Menten Model

What is the physiological role of glucokinase in the liver?

p.17

Enzyme Kinetics and Michaelis-Menten Model

What is the role of alcohol dehydrogenase (ADH) in ethanol metabolism?

p.17

Mechanisms of Enzyme Inhibition and Activation

Which enzyme is primarily responsible for detoxifying acetaldehyde?

p.17

Enzyme Kinetics and Michaelis-Menten Model

What does a high Km value indicate about an enzyme's affinity for its substrate?

p.17

Isoenzymes and Their Clinical Significance

What is the consequence of an ALDH2 mutation?

p.17

Mechanisms of Enzyme Inhibition and Activation

What is the primary function of ALDH1 in ethanol metabolism?

p.18

Enzyme Kinetics and Michaelis-Menten Model

What type of curve do allosteric enzymes typically show in a reaction velocity vs substrate concentration plot?

p.18

Mechanisms of Enzyme Inhibition and Activation

What is the reason for the sigmoidal curve observed in allosteric enzymes?

p.18

Enzyme Kinetics and Michaelis-Menten Model

What happens to the reaction velocity of allosteric enzymes at low substrate concentrations?

p.18

Classes of Enzymes

Which of the following is an example of an allosteric enzyme?

p.18

Mechanisms of Enzyme Inhibition and Activation

What is the effect of positive cooperativity in allosteric enzymes?

p.19

Isoenzymes and Their Clinical Significance

What is a key feature of isoenzymes?

p.19

Isoenzymes and Their Clinical Significance

Which isoenzyme is a diagnostic marker for heart attacks?

p.19

Isoenzymes and Their Clinical Significance

What does a high level of CK-MB indicate?

p.19

Isoenzymes and Their Clinical Significance

Which isoenzyme is associated with liver disease?

p.19

Isoenzymes and Their Clinical Significance

What is the significance of measuring isoenzymes in clinical practice?

p.20

Multienzyme Complexes and Their Efficiency

What is a multienzyme complex?

p.20

Multienzyme Complexes and Their Efficiency

What is one key feature of multienzyme complexes?

p.20

Multienzyme Complexes and Their Efficiency

Which of the following is an example of a multienzyme complex?

p.20

Multienzyme Complexes and Their Efficiency

How does a multienzyme complex increase metabolic efficiency?

p.20

Multienzyme Complexes and Their Efficiency

What is the role of cofactors in the Pyruvate Dehydrogenase Complex?

p.21

Enzyme Activation and Regulation

What is the process of enzyme activation primarily about?

p.21

Enzyme Activation and Regulation

What characterizes a constitutively active enzyme?

p.21

Enzyme Activation and Regulation

How does allosteric activation work?

p.21

Enzyme Activation and Regulation

Which of the following is an example of zymogen activation?

p.22

Enzyme Activation and Regulation

What is the term for inactive enzymes that require cofactors to become active?

p.22

Enzyme Activation and Regulation

Which of the following is an example of a cofactor required for enzyme activation?

p.22

Enzyme Activation and Regulation

What is the most common type of covalent modification that regulates enzyme activity?

p.22

Enzyme Activation and Regulation

What happens to glycogen phosphorylase when it is phosphorylated?

p.22

Enzyme Activation and Regulation

What is the role of allosteric regulation in enzyme activity?

p.23

Mechanisms of Enzyme Inhibition and Activation

What is enzyme inhibition?

p.23

Mechanisms of Enzyme Inhibition and Activation

Which type of inhibition involves the inhibitor binding covalently to the enzyme?

p.23

Mechanisms of Enzyme Inhibition and Activation

What is a key significance of enzyme inhibition?

p.23

Mechanisms of Enzyme Inhibition and Activation

What happens during reversible inhibition?

p.23

Mechanisms of Enzyme Inhibition and Activation

Which type of inhibitor distorts the shape of the active site without binding to it?

p.24

Mechanisms of Enzyme Inhibition and Activation

What is a characteristic of competitive inhibition?

p.24

Mechanisms of Enzyme Inhibition and Activation

How can competitive inhibition be overcome?

p.24

Mechanisms of Enzyme Inhibition and Activation

What distinguishes non-competitive inhibition from competitive inhibition?

p.24

Mechanisms of Enzyme Inhibition and Activation

What is an example of uncompetitive inhibition?

p.24

Mechanisms of Enzyme Inhibition and Activation

Which type of inhibition cannot be overcome by increasing substrate concentration?

p.25

Mechanisms of Enzyme Inhibition and Activation

What effect does competitive inhibition have on Km?

p.25

Mechanisms of Enzyme Inhibition and Activation

In a Lineweaver-Burk plot for non-competitive inhibition, where do the lines intersect?

p.25

Mechanisms of Enzyme Inhibition and Activation

What happens to Vmax in the case of uncompetitive inhibition?

p.25

Mechanisms of Enzyme Inhibition and Activation

How does non-competitive inhibition affect Km?

p.25

Mechanisms of Enzyme Inhibition and Activation

What is the characteristic feature of the Lineweaver-Burk plot for uncompetitive inhibition?

p.26

Role of Enzymes in Diagnosis and Therapy

What role do enzymes play in diagnosis?

p.26

Role of Enzymes in Diagnosis and Therapy

How can enzymes be used therapeutically?

p.26

Role of Enzymes in Diagnosis and Therapy

What is enzyme replacement therapy (ERT)?

p.26

Role of Enzymes in Diagnosis and Therapy

Why are enzymes considered essential tools in modern medicine?

p.26

Role of Enzymes in Diagnosis and Therapy

What is one of the key diagnostic roles of enzymes?

p.27

Mechanisms of Enzyme Inhibition and Activation

What is the primary cause of gout as described in the text?

p.27

Mechanisms of Enzyme Inhibition and Activation

What is the mechanism of action of Allopurinol in treating gout?

p.27

Mechanisms of Enzyme Inhibition and Activation

Which of the following statements is true regarding Febuxostat?

p.27

Mechanisms of Enzyme Inhibition and Activation

How does the inhibition by Allopurinol differ from that of Febuxostat?

p.27

Mechanisms of Enzyme Inhibition and Activation

What is the clinical use of Allopurinol in the context of gout?

p.28

Role of Enzymes in Diagnosis and Therapy

What does CVD stand for?

p.28

Role of Enzymes in Diagnosis and Therapy

Which enzyme is specifically mentioned as a biomarker for myocardial infarction?

p.28

Mechanisms of Enzyme Inhibition and Activation

What is the mechanism of action of Statins in relation to cholesterol?

p.28

Mechanisms of Enzyme Inhibition and Activation

What is the effect of inhibiting HMG-CoA reductase with Statins?

p.28

Role of Enzymes in Diagnosis and Therapy

What pattern is observed with LDH in myocardial infarction diagnosis?

p.29

Role of Enzymes in Diagnosis and Therapy

What gene is mutated in Gaucher's disease?

p.29

Characteristics and Actions of Enzymes

What is the primary consequence of Gaucher's disease at the cellular level?

p.29

Mechanisms of Enzyme Inhibition and Activation

What is the mechanism of enzyme replacement therapy (ERT) for Gaucher's disease?

p.29

Role of Enzymes in Diagnosis and Therapy

Which of the following is a common drug used in enzyme replacement therapy for Gaucher's disease?

p.29

Role of Enzymes in Diagnosis and Therapy

What is a significant financial aspect of enzyme replacement therapy for Gaucher's disease?

p.30

Mechanisms of Enzyme Inhibition and Activation

What is the role of ẞ-lactamase in bacterial infections?

p.30

Classes of Enzymes

Which of the following is an example of a resistant bacterium that may produce ẞ-lactamases?

p.30

Role of Enzymes in Diagnosis and Therapy

What is the purpose of using ẞ-lactamase inhibitors in clinical settings?

p.30

Characteristics and Actions of Enzymes

What type of disease is primarily associated with ẞ-lactamase-producing bacteria?

p.30

Enzyme Activation and Regulation

How can enzyme inhibitors be used in diagnostic tests?

p.31

Role of Enzymes in Diagnosis and Therapy

What enzyme is primarily involved in the measurement of urea in the blood?

p.31

Role of Enzymes in Diagnosis and Therapy

What does an increase in Blood Urea Nitrogen (BUN) indicate?

p.31

Role of Enzymes in Diagnosis and Therapy

What is the clinical significance of decreased urea levels in the blood?

p.31

Role of Enzymes in Diagnosis and Therapy

How is urea measured in laboratory assays?

p.31

Role of Enzymes in Diagnosis and Therapy

Where is urea produced in the body?

p.32

Role of Enzymes in Diagnosis and Therapy

What does an increase in Alkaline Phosphatase (ALP) indicate in periodontal disease?

p.32

Role of Enzymes in Diagnosis and Therapy

Which enzyme is used for non-invasive early detection of oral cancers?

p.32

Role of Enzymes in Diagnosis and Therapy

What is the role of Lysozyme in oral health?

p.32

Role of Enzymes in Diagnosis and Therapy

What is the purpose of enzyme-based diagnostic kits like the Urease test?

p.32

Role of Enzymes in Diagnosis and Therapy

Which therapeutic enzyme is derived from plants and used in dental procedures?

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