Enzymes
Objectives Define Catalyst, Enzymes, Biological Catalyst Describe how enzymes work Describe the effect of changes in temperature an pH on enzyme activity
Catalyst: a substance that speeds up a chemical reaction and is not changed by the reaction Enzymes: proteins made by organisms that speed up chemical reactions Known as biological catalysts Scientists say enzymes speed up, catalyze roughly 4,000 reactions in the body.
Enzymes have… 5 important qualities: All are proteins Each enzyme catalyzes 1 reaction Enzymes can be used again and again Enzymes are influenced by temperature work best at a particular temp Enzymes are influenced by PH work best at a particular pH
Enzymes change the substrate Into the product
For example: enzymes break down sugars for digestion
Enzyme Properties Enzymes are made inactive by high temps As temperature increases, the enzyme activity can increase. Too high temperature Denatures the enzyme (causes them to stop working).
Effect of Temperature on Enzyme Activity As temperature ____________, enzyme activity can _________. However, very high temperatures ______ enzymes, or cause them to stop working.
What is pH? pH is a measure of acidity Water has a neutral pH of 7 A change in pH can disrupt an enzyme’s shape and structure causing it to unravel, or denature.
Effect of pH on Enzyme Activity
Bellwork November 2012 Draw graph as shown on next slide and then write the correct answer, as shown in red ,under your drawing.
The graph shows how the rate of an enzyme-controlled reaction changes with temperature. What is happening within “The temperature range marked “X”? a) The enzyme is becoming denatured.” b) The enzyme is being used up.” c) The reaction is occurring at body temperature.” d) The reaction is occurring at the optimum temp.”
Enzymes are named for what they catalyze Protease = breaks down Protein Lipase = breaks down Lipids (fats) Carbohydrase = breaks down carbohydrates Maltase = breaks down Maltose Sucrase = breaks down Sucrose Amylase = breaks down Starch What are the substrates and products?
Not All Enzymes Are Created Equal Stomach enzymes work in a super acidic environment of pH 2. A little way down the digestive tract, intestine enzymes need a pH of 8.