Enzymes

Question 1

What is the “lock and key” model?

Answer 1

Each enzyme has a very specifically shaped active site which can only fit one type of susbstrate in it. The matching substrate and enzyme will then form an enzyme-substrate complex. The enzyme will either break apart things or join together things. It will then release the products.

Question 2

What factors affect the rate of enzyme activity?

Answer 2

Temperature, pH, substrate concentration and enzyme concentration

Question 3

How does temperature affect the rate of enzyme activity?

Answer 3

The rate of enzyme activity increases with temperature until the temperature reaches its optimum point (37 degrees celsius). If the temperature goes higher than that point the enzyme will denature and the rate will start to decrease.

Question 4

How does pH affect the rate of enzyme activity?

Answer 4

pH also increases with the rate of enzyme activity until the optimal point (pH 7 or neutral). If it goes past this point the bonds won’t be in place and the enzyme will denature. The curve for pH is much more symmetrical than the one for temperature

Question 5

How does substrate concentration affect the rate of enzyme activity?

Answer 5

The rate of enzyme activity will increase with substrate concentration but only up to a certain point as there are limited active sites on enzymes that these substrates can fill up

Question 6

How does an enzyme catalyst affect the rate of reaction?

Answer 6

The reaction will start to happen much faster with an enzyme but it will end up at the same point, albeit much faster than if there was no enzyme