Module 2 Section 4 - Factors Affecting Enzyme Activity Flashcards
What are the four factors that affect enzyme activity
-Temperature
-pH
-Enzyme Concnetration
-Substrate concentration
When the rate of an enzyme controlled reaction is increased what is also increased
The temperature
More heat means ….
More kinetic energy
More kinetic energy means…..
Molecules moves faster
Because the molecules move faster, what does it lead to
Makes the enzymes more likely to collide with the substrate molecule
The energy of collisions increases meaning
Each collision is more likely to result in a reaction
What happens if the temperature is too high
The reaction stops
The rise in temperature makes the enzymes molecules….
Vibrate more
If the temperature goes above a certain level….
This vibration breaks some of the bonds that hole the enzyme in shape
The active site
Changes shape and the enzyme and substrate no longer fit together
When the active site changes shape and the enzyme and substrate don’t fit together it means….
That the enzyme is denatured - no longer functions as a catalyst
All enzymes have an….
Optimum pH
What do most human enzymes best work at
pH 7 (neutral), but there are exceptions
What happens if the pH is above or below optimum
The H+ and OH+ ions found in acids and alkalis can mess up the ionic bonds and hydrogen bonds that hole enzyme tertiary structure in place. This makes the active site change shape meaning the enzyme becomes denatured
The more enzyme molecules there are in a solution…
the more likely a substrate molecule is to collide with one and form an enzyme substrate complex
Increasing concentration of enzyme….
Increases rate of reaction
What happens if the amount of substrate is limited
There will be a point where there are more than enough enzyme molecules to deal with all available substrate so adding more enzyme has no further effect
The higher the substrate complex
The faster the reaction
The more substrate molecules means….
A collision between substrate and enzyme is more likely so more active sites will be used
What happens after the saturation point
There are so many substrate molecules that the enzymes have about as they can cope with and adding more substrate makes no difference to the rate of reaction
Substrate concentration decreases….
With time during a reaction, so if no other variables are changed the rate of reaction will decrease over time too.
