30 Questions
What is the role of enzymes in the body?
They increase the rate of reactions without being changed in the overall process
How are enzymes assigned names?
They are assigned two names: a short recommended name and a systematic name
What is the suffix commonly used in enzyme names?
-ase
Why are systematic names used?
To identify enzymes without ambiguity
How are enzymes classified in the systematic naming system?
Into six major classes with numerous subgroups
What is a characteristic of some enzymes that retain their original trivial names?
They do not give a hint of the associated enzymatic reaction
What is the term for the active enzyme with its nonprotein component?
Holoenzyme
What type of molecules can bind to enzymes and increase their activity?
Either metal ions or small organic molecules
What is the purpose of localizing enzymes in specific organelles within the cell?
To isolate the reaction substrate or product from other competing reactions
What is the role of a catalyst in a chemical reaction?
To accelerate the reaction
What is the theory that explains the action of a catalyst?
Transition state theory
What is the term for a coenzyme that only transiently associates with the enzyme?
Cosubstrate
What is the suffix attached to a description of the chemical reaction catalyzed by an enzyme?
-ase
What is the role of the active site in an enzyme molecule?
To bind the substrate and participate in catalysis
What is the result of the binding of the substrate to the enzyme?
A conformational change in the enzyme
How much faster do enzyme-catalyzed reactions proceed compared to uncatalyzed reactions?
103–108 times faster
What is the turnover number of an enzyme?
The number of molecules of substrate converted to product per enzyme molecule per second
What is a characteristic of enzymes in terms of their specificity?
They interact with one or a few substrates and catalyze only one type of chemical reaction
What is the typical pH range at which most enzymes function?
Between 6 and 8
What happens to the enzyme activity when the product concentration increases?
The enzyme activity decreases
What is the effect of ultraviolet radiation on certain enzymes?
It inactivates the enzyme
What does a low Km value indicate about an enzyme's substrate affinity?
A strong substrate affinity
At which pH does the enzyme pepsin function best?
pH 2
What is the effect of extreme pH on enzyme activity?
The enzyme becomes totally inactive
What is the term for the energy required to convert a substance from its ground state to its transition state?
Activation energy
How does the rate of an enzyme-catalyzed reaction change when the concentration of enzyme is increased?
It increases
What happens to the velocity of an enzyme reaction when the temperature is increased?
It increases up to a maximum, then declines
What is the optimum temperature range for most enzymes?
35°C–40°C
Why do some enzymes, like Taq DNA polymerase, remain active at high temperatures?
Due to their highly stable structure
What is the term for the increase in enzyme velocity when the temperature is increased by 10°C?
Q10
This lecture covers the basics of enzymes, their role in mediating biochemical reactions in the body, and how they direct metabolic events. Learn about the nature of enzymes and their functions in this clinical biochemistry lecture.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
