b4 03 enzymes and temperature

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•Describe how temperature affects enzyme action•H: explain changes in enzyme activity with pH in terms of changes to the shape of the active siteexplain why enzymes operate best in their optimum conditions

Enzymes and temperature

Keywords- Denature, enzyme, optimum, active site, lock and key model,

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Why plants do not grow much in the winter (in the UK)?

Ideas may include less light and so less photosynthesis and lower temperatures.

This lesson will investigate how temperature can affect how well cells function. This ultimately depends on the enzymes that catalyse chemical reactions inside cells

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What is the name of chemicals that control chemical reactions in cells ________and what they are made of _________

Egg white is protein – high temperatures have a significant effect on the structure of most proteins

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Review homework questions.

Note: if you had more difficulty with the questions. There is an opportunity to work with them during the next group activity.

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Animation IB4.2.4 Enzymes (part two) to investigate what happens to the reaction when the temperature is increased. complete Activity AB4.3.1 Enzymes and temperature

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‘Ice fish’ such as Antarctic cod are active at 2°C because their enzymes work best at low temperatures. Most organisms would be dead or very sluggish at 2°C.

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How an enzyme reaction can be stopped by a rise in temperature.A change is shape of the active site, the molecule no longer fits!

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Bacteria living in hot springs have enzymes that withstand high temperatures.

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The optimum temperature of an enzyme. The reaction rate is plotted at different temperatures – all other conditions are kept constant

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The enzyme used in this reaction has an optimum pH of 7.0

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:Look back through your work the worksheet enzymes and temperature. Here we used an animation to predict what would happen to the collisions, speed and oxygen output when the temperature changed.