Pectinase Prelab

Please copy the following definitions: (on handout)

Chemical reaction: when atoms are rearranged in a molecule or molecules.

Enzyme: a protein that speeds up a chemical reaction

Substrate: the substance an enzyme changes Catalyst: anything that speeds up a reaction

The real chemical name for pectin is polygalacturose. What is the name of the monosaccharide it is made of?

“Ga-lac-tur-ose”

It’s the monosaccharide subunit of poly-

galactarose.

Science words always make

sense, because they’re designed

to be used by speakers of

every language

Check Yourself:

There’s lots of different kinds of “sugars”out there.

Galacturose has 6 carbon atoms – how many oxygen atoms must it have?

Here’s a small part of the long chain…

This is the bond we’ll be breaking in the lab!!!

Pectinase is the

protein we’ll be using in the lab.

ENZYME

SUBSTRATE

Pectinase attaches to pectin at the active site…

…And then breaks a bond in the polysaccharide!

Some proteins (like Pectinase) are enzymes. Different enzymes speed up

all different kinds of reactions in organisms!

SUBSTRATE

Enzyme

Enzymes are very selective about whichsubstrates they bind.In other words,

They’re Specific.

Apples have lots of pectin

We will be measuring the effect of pectinase by measuring how fast

liquid from applesauce drips through a filter.

What effect will chopping pectin into little pieces have on the amount of juice you collect?

Homework:

Write a hypothesis on page 2 of the lab report based on what you know.

It should answer the question “What will pectinase do to pectin in applesauce?”

Hypothesize!

Predict

• Remember what a prediction is: An if… then statement that will test your hypothesis using data from the experiment.

• If… [hypothesis] then [data you expect]

• Write a prediction on your lab report

Background

• With the time that remains, begin writing your background section on page 1 of the lab report. Use the bullet points listed to guide your response.