ENZYMES

Objective: students will participate in saltine cracker demonstration and take notes on enzymatic activity

Keep the cracker in your mouth WITHOUT eating it for the

length of the video• AFTER WATCHING THE VIDEO, EXPLAIN WHAT HAPPENED TO THE

CRACKER

• http://www.youtube.com/watch?v=XTUm-75-PL4

• AFTER WATCHING THE VIDEO, EXPLAIN WHAT HAPPENED TO THE CRACKER

ENZYMES ARE PROTEINS

ENZYMES ARE PROTEINS

ENZYMES ARE PROTEINS

ENZYMES ARE PROTEINS

ENZYMES ARE PROTEINS

Enzymes– build molecules

• synthesis

– breakdown molecules• digestion

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ENZYMES ARE…..

• A CATALYST…MEANING THEY SPEED UP REACTIONS IN THE BODY.

• WHAT WOULD HAPPEN TO THE FOOD YOU EAT IF THERE WERE NO ENZYMES????

• ENZYMES LOWER THE AMOUNT OF ENERGY NEEDED TO DO A REACTION– MAKES REACTION OCCUR FASTER AND

EASIER!

• ENZYMES ARE VERY SPECIFIC!

• EVERY MOLECULE HAS A SPECIFIC ENZYME THAT CAN BIND WITH IT TO CREATE A REACTION– LIPASE WILL ONLY BIND WITH LIPID– LACTASE WILL ONLY BIND WITH LACTOSE– GLUCASE WILL ONLY BIND WITH

GLUCOSEOh, I get it!They end in -ase

OH THOSE PICKEY ENZYMES!

– each enzyme needs to be the right shape for the job

– LIKE A LOCK AND KEY• ONLY A SPECIFIC KEY CAN FIT IN LOCK TO

OPEN A DOOR

• ONLY A SPECIFIC ENZYME CAN FIT IN A MOLECULE TO START A REACTION

Enzymes

• View how they are specifichttp://www.kscience.co.uk/animations/anim_2.htm

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Enzyme vocabulary• Enzyme

– helper molecule

• Substrate– molecule that enzymes work on

• Enzyme-substrate complex– enzyme & molecule temporarily joined

• Active site– part of enzyme

that substrate molecule fits into

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• ENZYMES DO NOT CHANGE AFTER A REACTION and ENZYMES CAN BE USED OVER & OVER AGAIN

• JUST LIKE A LOCK AND KEY…WHEN YOU PUT THE KEY IN A LOCK AND TAKE IT OUT AGAIN…DID IT CHANGE? NO!!!!

WHAT CAN AFFECT HOW WELL AN ENZYME WORKS?

• TEMPERATURE (TOO COLD OF TEMPERATURE COULD MEAN SLOWER REACTION)

• PH

• CONCENTRATION (NUMBER OF ENZYMES)

In review….

• http://www.youtube.com/watch?v=WfAswYmwb_s

COPY INTO NOTEBOOK