Enzymes Flashcards
What are enzymes?
Enzymes are biological catalysts that speed up metabolic reaction in living organisms
How do enzymes affect it cells, systems and organisms?
It can affect the structure and function in the substrate
What is the turnover number?
The number of reactions that an enzyme can catalyse per second
What is the difference between enzymes and temperatures as catalysts?
Enzymes are more specific to a substrate, and doesn’t produce any unwanted profit and rarely makes mistake
How are enzymes structured?
It is a protein with a tertiary structure and a specific active site that is complementary to its target
How are enzymes made?
It is made by protein synthesis and can be affected if their are any mutations in the DNA
How many amino acids is the active site?
It is 6 - 10 amino acids long that connect to the surface of the molecule
Why is the active site specific?
They are very specific because they need to be complementary to a specific substrate
What affects the enzymes shape and why?
An increased temperature and pH because when it increases the proteins tertiary structure so it isn’t complementary to its substrate
What are intracellular enzymes?
Enzymes that are in the cell
What do enzymes do in the cells?
Enzymes
What is a catabolic reaction?
A reaction that break down big molecules into small molecules
What is an anabolic reaction?
A reaction that build up small molecules into big molecules
Give an example of where enzymes are used?
Photosynthesis and respiration
What is catalase used for?
It is found in all cells and is used to break down H2O2 quickly that is made after many reactions
What is a catalase’s structure?
It has 4 polypeptide chains and had an iron haem group
What conditions does catalase need without an enzyme?
pH 7
450 degrees
What conditions does catalase need with an enzyme?
pH 4 - 11
90 degrees
What are extracellular enzymes?
Enzymes that are out of the cell
What is an example of an extracellular enzymes?
They digest lipids, carbs and proteins in the small intestines
What is amylase used for?
It digests polysaccharides into monosaccharides
What is the lock and key theory?
The substrate only fits the enzyme because the active sites tertiary structure is complementary the substrate so it fits
What happens as the enzyme and substrate as they bump into each other?
The enzymes and substrates have kinetic energy each have kinetic energy and move around and fit into each other
What happens when the enzyme and substrate combine?
The form an enzyme - substrate complex
What happens after the substrate changes with the enzyme?
The substrate is released and the enzyme can be reused for another reaction
What is the induced fit hypothesis?
The substrate goes into the enzyme and changes it shape to fit around the substrate
What happens to the active site in the induced fit hypothesis when a substrate enters?
The side chains change subtly after the binding to give it a more precise conformation to fit exactly
How do enzymes reduce activation energy?
It brings the substrate closer and needs less energy and heat for the reaction to take place
