Presentation on theme: "Enzymes. Learning Target: 1. Recognize enzymes as catalysts: a. Protein molecules that function to lower activation energy (increase rate of a reaction)"— Presentation transcript:
Learning Target: 1. Recognize enzymes as catalysts: a. Protein molecules that function to lower activation energy (increase rate of a reaction) b. Reusable and specific in function c. Altered by high temperature, pH, and metals (lead, mercury) 2. Recognize how the enzyme-substrate complex model demonstrates the function of enzymes.
Enzymes Objectives continued: 3. Recognize a reason why an enzymes ability to lower activation energy would be beneficial to a living organism 4. Be able to collect, graph, and analyze data relating to enzymes reactions. 5. Explain catalase enzyme action based on the class demo.
Enzymes A protein that speeds up a chemical reaction Biological Catalyst Recall: Inorganic Chemistry Reactants Catalyst → Products Organic Chemistry Substrate Enzyme → Products
Enzymes activation energy Energy needed to start a reaction Enzymes lower the amount of activation energy needed to start a reaction
Enzyme Functions Involved in nearly all metabolic processes. Speeds up the reactions in digestion of food synthesis of molecules - storage of energy release of energy (aids in breaking molecules into monomers) Used in transmission of nerve impulses muscle contraction cellular energy
Enzyme Characteristics Remains unchanged in a reaction Never used up Each enzyme has a specific job Ex. Amylase – starch enzyme Lactase – lactose enzyme Catalase – hydrogen peroxide enzyme(byproduct of cell metabolism-poisonous if can’t break down) Sucrase – sucrose enzyme
Enzymes Terms: Substrate – The molecule(s) that the enzyme acts upon Active Site – the location on the enzyme where the substrate binds Theories: Lock and Key theory- specific fit between the substrate and enzyme Induced Fit Model- enzyme changes shape a little to fit with the substrate “molds to fit”
Coenzyme – a helper, such as vitamins Inhibitor – molecule that blocks or changes the active site so the substrate cannot bind (2 Types) Reversible: Competitive Inhibitors – attaches to active site … competes with substrate for site 1. inhibitor is chemically similar to the substrate 2. Temporary attachment (doesn’t alter active site)
Non-Competitive Inhibitors – binds with the enzyme at a location other than the active site, altering the shape of the active site
Enzymes Types of Inhibitors continued Irreversible Permanently inactivates the enzyme Ex. Poison, exposure to heavy metals such as mercury and lead
Denaturation – active site of the enzyme is altered, Causes: temperature, heavy metals, pH