enzymes Flashcards
What is a catalyst?
a substance that can speed up a chemical reactions without itself being chemically unchanged at the end of the reaction
What are enzymes?
They are proteins that function as biological catalysts. They catalyse or speed up the rate of chemical reactions and still remain chemically unchanged at the end of it.
Where are most enzymes found?
In living organisms
Why are enzymes required to break large molecules into simpler and smaller substances?
So that they are 1) soluble in water and 2) small enough to diffuse through the cell membrane
Amylase digests?
Starch into maltose
Maltase digests?
maltose into glucose
Protease digests?
proteins into polypeptides, then to amino acids.
Lipase digests?
fats into fatty acids and glycerol
What are examples of digestive enzymes
1) amylase
2) maltase
3) protease
4) lipase
How does an enzyme work?
enzymes are highly specific, which means that each chemical reaction inside a cell is catalysed by a unique enzyme.
What is the hypothesis used?
Lock and key hypothesis
enzyme reactions depends on the presence of?
Active sites
In the lock and key hypothesis, what does the key act as?
The substrate
In the lock and key hypothesis, what does the lock act as?
The enzyme / active site of the enzyme
When the substrate binds to the active site of an enzyme, what does it form?
An enzyme-substrate complex.
What is the processes in the lock and key hypothesis?
1) substrate enters the active site of the enzyme
2) Substrate binds to the active site of the enzyme.
3) Chemical reactions occur while substrate is attached to the enzyme. The substrate is then converted to the products.
4) Products leave the active site of the enzyme, enzyme remaining chemically unchanged and is able to catalyse another reaction
What are some characteristics of enzymes?
1) They speed up chemical reactions
2) They are specific in action
3) Enzymes are required in small quantities and remain chemically unchanged at the end of reactions.
4) Works best at an optimum temperature of pH
What can enzymes be affected by?
Changes in temperature or pH
Define denaturation
It is the change in the three-dimensional structure of an enzyme or any other soluble protein caused by heat or chemicals such as acids or alkalis.
What are examples of digestive enzymes
1) amylase
2) maltase
3) protease
4) lipase
When do enzymes denature?
enzymes denature upon exposure to temperature above its optimum temperature. / takes place when there are extreme changes in pH and at a temperature above the optimum.
