Chapter 5 Flashcards
Enzymes
What are Enzymes?
Enzymes are proteins that act as biological catalysts, involved in all metabolic reactions.
What is a catalyst?
A catalyst is a substance that speeds up chemical reactions, but itself isn’t changed.
Only a small amount is needed.
What life processes are enzymes used for?
The reactions they catalyse are essential for life, such as respiration, and digestion
Why are enzymes important for reactions to sustain life?
Without enzymes, reactions will happen too slowly at body temperature, and the organism will not survive.
What is the Active site of an enzyme?
An enzyme has a shape called the Active site that fits only the substance it acts on.
What is a Substrate and products?
- The substance on which an enzyme acts is called a substrate.
- Molecules produced are called products.
What does it mean when an Enzyme is specific?
This means it only acts on one substance. This is due to its Active site that’s complementary only to its substrate.
What is an enzyme-substrate complex?
When enzymes combine with the substrate, an enzyme-substrate complex forms temporarily.
What is the effect of Temperature on enzymes?
As temperatures increase, the rate of chemical reactions increase due to increase in the enzyme activity (kinetic energy too).
What is the Optimum temperature for Enzymes?
The Optimum temperature is 37c.
When do enzymes become denatured? What does this mean?
Above 50c, enzymes become denatured. This means the shape of the enzyme changes, and can no longer combine with its substrate.
What is the effect of PH on enzymes?
- Different enzymes work best at different levels of Acidity and Alkalinity.
- Most enzymes work best at PH 7.
Explain the effect of change in temperature in terms of Kinetic energy and collisions
As temperature increases, particles gain more kinetic energy.
The enzyme and substrate molecules move faster, leading to more collisions and reactions.
What are INTRA-cellular enzymes?
These are the enzymes that stay inside the cell to speed reactions in the Nucleus and Cytoplasm.
What are EXTRA-cellular enzymes?
These are the enzymes that go outside of the cell for reactions.
What is Catalase?
Catalase is a very common enzyme found in most cells that can break down 40,000 molecules of Hydrogen Peroxide to Water and Oxygen per second.
2H2O2 -> 2H2O + O2
