factors affecting enzyme action Flashcards
how does ph affect enzyme function
if ph is too extreme(over 7) - active sight may be altered and enzyme may not work
how does temp affect enzyme function
-rise in temp increases kinetic energy of molecules.
-the molecules move more rapidly ,collide more often.
-In enzyme-catalysed reaction, means enzyme and substrate molecules come together more often in given time.
-more effective collisions resulting in more enzyme-substrate complexes being formed and s rate of reaction increases.
What happens to the bonds in enzymes as the temperature increases?
-temp rise causes hydrogen and other bonds in enzyme molecule to break.
-first, substrate fit less easily into changed active site, slowing rate of reaction.
-for many human enzymes this may begin at temps of around 45 degrees.
What is denaturation?
permanent change in the enzyme and, once occurred, the enzyme doesn’t function again.
What is the effect of substrate concentration on the rate of enzyme reaction?
-If the concentration of enzyme is fixed and substrate concentration is slowly increased, the rate of reaction increases in proportion to the concentration of substrate.
What is the effect of enzyme concentration on the rate of reaction?
if excess of substrate, leads an increase in rate of reaction. If you therefore increase the enzyme concentration, some of excess substrate can now also be acted upon and rate of reaction will increase.
If, however, the substrate is limited, then any increase in enzyme concentration will have no effect on the rate of reaction.
How do we investigate effect of a named variable on rate of reaction?
When investigating effect of named variable on rate of an enzyme reaction all other variables must be kept constant.
e.g. , if measuring effect of temperature, then pH, enzyme concentration and substrate concentration must be kept constant and all possible inhibitors should be absent.
What happens to enzymes at around 60 degrees?
The enzyme is so disrupted that it stops working altogether. It is said to be denatured.
Define the term optimum temperature
The optimum temperature is the temperature which enzyme works fastest.
All enzymes have the same optimum pH.
False.
Some enzymes produced in acidic conditions have lower optimum pH,
-while those produced in alkaline conditions have higher optimum pH.
What happens after a reaction has occurred in the active site of an enzyme?
After reaction occurred, products leave enzyme’s active site - they no longer fit it, and enzyme is free to take up another substrate.
how does ph affect
too high or low- it interferes with bonds holding enzymes together.
-changes shape of active sight -denaturing enzyme
