5.1 Enzymes Flashcards
What is a catalyst?
A catalyst is a substance that speeds up a chemical reaction and is not used up in the process.
What are enzymes?
Enzymes are proteins that act as biological catalysts to speed up reactions in living things.
Why are enzymes important for living things?
Enzymes are important because they speed up reactions that are necessary for life.
What is the “Lock and Key Model”?
The “Lock and Key Model” says that the shape of an enzyme’s active site matches its substrate, like a key fits into a lock.
What happens if the temperature is too high for an enzyme?
If the temperature is too high, the enzyme’s shape changes, and it can no longer work properly. This is called denaturation.
What is the best temperature for enzymes in humans?
The best temperature for enzymes in humans is about 37°C.
How does temperature affect enzyme activity?
As temperature increases, enzymes work faster because molecules move more quickly. But if it’s too hot, enzymes can denature and stop working.
How does pH affect enzyme activity?
Enzymes work best at a specific pH. If the pH changes too much, the enzyme’s shape can change, and it may not work properly.
What happens when an enzyme denatures?
When an enzyme denatures, its shape changes, and it cannot bind to its substrate anymore, so it stops working.
What is an enzyme-substrate complex?
An enzyme-substrate complex is when the enzyme and substrate bind together to start the reaction.
What does “substrate specificity” mean?
Substrate specificity means that each enzyme can only work with one type of substrate that fits its active site.
What is the active site of an enzyme?
The active site is the part of the enzyme where the substrate fits, and the reaction happens.
How does pH change affect enzyme activity?
Changes in pH can change the shape of the enzyme’s active site, making it unable to bind to its substrate, which stops the reaction.
What happens to enzyme activity if the temperature is too low?
If the temperature is too low, enzymes move slower, and the reaction happens more slowly.
Why are enzymes needed in metabolism?
Enzymes help speed up reactions in metabolism, making sure they happen fast enough to keep us alive.
What is denaturation?
Denaturation is when an enzyme’s shape changes because of high temperature or extreme pH, and it can’t work anymore.
How does temperature affect enzyme activity?
At higher temperatures, enzymes work faster until they get too hot and denature. Lower temperatures make enzymes work more slowly.
What happens to enzymes if the pH is too high or too low?
If the pH is too high or too low, the enzyme’s shape changes, and it stops working.
How do enzymes help in digestion?
Enzymes break down food into smaller molecules that the body can absorb, like breaking down proteins into amino acids.
Can enzymes be used again?
Yes, enzymes can be used again because they are not changed by the reaction.
