U01L04: ENZYMES

U01L04 ENZYMES An enzyme is a biological catalyst that speeds up the rate of a chemical reaction. It will not cause a chemical reaction to occur that would not occur naturally. In biological systems, temperature and pH (acidity) affect an enzyme’s ability to function. At too high a temperature, enzymes denature and break down, therefore losing their functionality. Label this activity: Graph Analysis. Analyze the graph and answer the following questions in your interactive notebook: 1. At what temperature do both enzymes have an equal rate of reaction? 2. At what temperature does Enzyme GlenKeppie have a maximum rate? 3. What conclusion can you draw to explain the effect of temperature on this graph? 4. Why might a high fever be dangerous for a human? What might happen? USE COMPLETE SENTENCES

FINISH LAB STATIONS Find the station that you left off at last class. Begin working through the station. When you are finished you can move to the next station. Do this until you have completed all the stations and you have all the answers to the questions in your notebook.

Research Plan You picked up the research plan assignment. Take 5 minutes to read over this document. Please ask any questions about this assignment that you have. This is a major grade for the first 6 Weeks.

Summer Work Quiz

Chemical Reactions

Cornell Notes Title your notes: Chemical Reactions Notes Add topics and summary after re-reading the notes.

Metabolism An incredibly large number of chemical reactions happen in your body every second of your life. Metabolism is a term used to describe all of the chemical reactions in a person’s body.

Reactants and Products In chemical reactions, molecules are changed in some way. The beginning molecule(s) are the reactants and the resulting molecule(s) are the products. R E A C T A N T S P R O D U C T S

This is an example of a chemical reaction: H2O2  H2O + O2   Hydrogen is broken down Water and Oxygen Peroxide in your cells into R E A C T A N T S P R O D U C T S

Hydrogen peroxide is made in your cells all the time Hydrogen peroxide is made in your cells all the time. However, it is toxic if it is not quickly broken down into water and oxygen, which are not toxic.

Chemical reactions don’t happen spontaneously though Chemical reactions don’t happen spontaneously though. Every chemical reaction requires a certain amount of energy in order for it to happen.

For a chemical reaction to take place, it has to “get over the hump,” as far as energy is concerned.

The amount of energy a chemical reaction requires is called its activation energy. A chemical reaction will not occur until it has this amount of energy. The activation energy corresponds to the top of the “hump” on the graph.

Label graph

The activation energy of most chemical reactions is too high for them to happen on their own. Luckily your body has enzymes to help.

Enzymes are proteins your body has that work by binding to a specific molecule and lowering its activation energy. The graph below represents the chemical reaction from above with an enzyme lowering its activation energy:

The “hump,” or activation energy, has been lowered so not as much energy is required for it to occur.

For example, your body has an enzyme called catalase that helps the cells break down hydrogen peroxide so it doesn’t poison you. CATALASE  +

When the activation energy is lowered, the chemical reaction happens much faster. Another word for an enzyme is a catalyst.

A catalyst speeds something up (enzymes speed up chemical reactions).

Re-read your notes and write a summary of these notes.