Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
12 Cards in this Set
- Front
- Back
Catalyst |
It's a substance that increases the rate of chemical reaction and is not changed by the reaction. |
|
Enzyme |
It's a protein that functions as a biological catalyst. |
|
Complementary shapes |
When an enzyme and substrate molecule fit together |
|
Substrate and Product |
The substance on which an enzyme acts is the substrate and the molecules produced are the ones called products. |
|
Anabolic reaction |
A reaction in which large molecules are built up from smaller molecules |
|
Enzyme-substrate complex |
When an enzyme is temporarily combined with the substrate |
|
Catabolic reactions |
Reactions that split large molecules into smaller ones |
|
Intracellular enzymes |
Enzymes that remain inside their cell speeding up reactions in the cytoplasm and nucleus. |
|
Extracellular enzymes |
Enzynes made in the cells are let out of the cell to do their work outside. |
|
Why enzymes are important in all living organisms in terms of reaction speed necessary to sustain life? |
Because enzymes speed up chemical reactions, without them chemical reactions became very slow and in that way they are too slow to maintain life. That's why we can't survive at high temperatures. |
|
The effect on changes in temperature in enzyme activity |
A fall in temperature slows them down and an increased temperature makes them faster as they gain more kinetic energy and there is more chance of collisions happening. Therefore the rate of reactiok increases too. Then when it gets above it optimum temperature the reaction will slow down because enzymes are proteins. They'll start to lose their shape and the active site will become deformed. Substrate molecules cannot fit with the enzyme anymore, stopping the reaction. Once it gets above 50°c it becomes denatured, the enzyme won't work anymore and there is no going back at this point. |
|
The effect of changes in pH on enzyme activity |
Extreme pH may denatured some enzymes irreversibly. As in higher temperatures , the active site becomes deformed. The enzyme and substrate molecules no longer have complementary shapes and so will not fit together. |