Enzymes: Biological Catalysts

 

In the last lesson we learned how catalysts can speed up a chemical reaction without being changed

An ENZYME is a special sort of catalyst that is made by living things
We make enzymes that help us digest food; control our cells; repair damage; etc.

Enzymes aren't as tough as the catalysts mentioned last lesson, though.
Enzymes need to have just the right levels of:

- temperature

- acid or alkali (pH)

 

If enzymes aren't given the right conditions they won't work as well - but our bodies need them to survive.

Human Salivary Amylase

 

Use the above passage to fill in these missing words ...

A catalyst is a substance that up a chemical reaction, and an is a type of catalyst that is made by all things.

The enzymes in our body do many things: they help us to digest , and control our .

Enzymes aren't as tough as other because they are affected by changes in and the amount of acid or alkali ( ).

If an enzyme doesn't have the right it won't work as well

We have to make sure our have the right conditions because we need them to survive.

You have had tries to get this right


We have an enzyme that is present in our spit (or saliva) called salivary amylase. This enzyme breaks starch down into sugar. It is said that if you chew a piece of bread for long enough it will start to taste sweeter - this is because the enzyme in our mouths is breaking down the bread starch into sugar

Amylase is a type of enzyme and IT ONLY WORKS ON STARCH. Enzymes are special catalysts because they only work on one molecule.

This means that you need a different enzyme for each chemical reaction

 

Now answer these questions ...

What substance speeds up a chemical reaction ?

What is a catalyst made by living things called ?

Enzymes can help us to digest what ?

An enzyme that breaks down starch is called what ?

When starch breaks down it makes what ?

Enzymes must have the right conditions of pH and what ?

A single enzyme will only work on how many types of molecule ?

Can you use the same enzyme for lots of different types of chemical reaction ?

The enzyme in our spit is called what ? Salivary

What is the scientific name for spit ?

You scored out of 10 on that test