Enzyme action Flashcards
What kind of protein is an enzyme?
Globular
What do enzymes act as?
Biological catalysts
Why is it necessary for organisms to have enzymes?
Enzymes speed up the rate of reactions without the need of high pressures or temperatures which would ultimately damage the cell.
Enzymes can only increase the rate of reaction up to a certain point. What is this point known as?
Vmax
What is meant by the activation energy?
The amount of energy needed to be applied for a reaction to start
What are the names of the two hypothesis for how enzymes behave?
Lock and key hypothesis
Enduced-fit hypothesis
What is the name for the part of the enzyme which is completely specific to a substrate?
The active-site
What is the name of the molecule which binds to the enzymes active-site?
The substrate
What is meant by the lock and key hypothesis?
Just like only a specific key can fit into the right lock, only a specific substrate will fit into the active site of the right enzyme.
What is said to be formed when the substrate is bound to the active site of an enzyme?
An enzyme-substrate complex
How is the substrate temporarily bonded to the enzymes active site?
The R-group within the active site of the enzyme forms temporary bonds with the substrate.
Draw a simplified diagram of the lock and key hypothesis
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What is meant by the induced fit hypothesis?
The active site of the enzyme changes shape slightly to completely fit the shape of the substrate.
Bond strength
How does, according to the induced fit hypothesis , the enzyme lower the activation energy of a reaction?
The weak interactions between the enzymes active site and the substrate induces changes in the enzymes tertiary structure. These changes put strain on the substrate and may weaken bond(s) within the molecule; thus lowering the activation energy.
What is the name for enzymes that act within cells?
Intracellular enzymes
Hydrogen peroxide is a toxin produced by many metabolic pathways. The enzyme catalase is responsible for breaking down this toxin. What does hydrogen peroxide get broken down to?
Oxygen and water
Enzymes (Updated) by the amoeba sisters
Give an example of an intracellular enzyme?
Catalase
What is the name given to enzymes that work outside of the cell?
Extracellular enzymes
Where are the two locations in which starch is digested?
The mouth and the small intestine
How is starch broken down in the mouth?
Starch is broken down by amaylse to form maltose.
Where in the body is amylase produced?
Salivary glands and the pancreas
How is maltose broken down in the small intestine?
Maltose is broken down by maltase into glucose.
What type of molecules does the enzyme trypsin brake down?
Proteins
What type of enzyme is trypsin?
A protease
Where in the body is trypsin produced?
The pancrease