Enzymes Flashcards
(12 cards)
Why are enzymes specific?
Enzymes are special because they fold into a shape that has a hole or indentation called the active site.
List some protein molecules found inside living organisms.
Proteins act as:
Hormones
Antibodies
Catalysts
Structural components of tissues such as muscles.
Describe the structure of protein molecules
Protein molecules are long chains of amino acids and these chains fold into a specific shape that enables other molecules to fit into the protein.
Define catalyst
Catalysts speed up chemical reactions and remains chemically unchanged.
Define enzymes
Enzymes are protein molecules which act as a biological catalyst. It changes the rate of chemical reactions without being affected itself at the end of the reaction.
Why are enzymes denatured by high temperatures
Increasing the temperature gives the molecules more kinetic energy allowing the reaction to occur faster
But if the temperature is too high, then it damages the active site, stopping the reaction and denature get the enzyme which is permanent.
Explain the effect of different Ph values on the activity of different enzymes
Each enzyme has an optimum Ph at which it operates.
If the solution is too acidic or alkaline, the H+ or OH- ions change the forces which holds the active site in its shape.
This prevents the substrate from binding, slowing the reaction until eventually the enzyme becomes denatured.
Food in the digestive system.
Enzymes break down large molecules of food into smaller molecules which can then be absorbed into the blood and distributed in the cells because food are made up of large insoluble molecules our bodies cannot absorb otherwise.
Names of digestive enzymes, organs which produce them and products of digestion.
Amylase is produced in the salivary gland and it catalyses the breakdown of starch into glucose.
Proteases are produced in the stomach and catalyses the breakdown of protein into amino acids.
Lipase’s are produced in the pancreas and catalyses the breakdown of lipids into fatty acids and glycerol.
Liver produces bile which is released in the small intestine and emulsify so fat.
Biological detergents.
Biological detergents contain proteases and lipases which break down protein and fat in stains so it gives you a cleaner wash as well as are more effective at low temperatures so saves electricity, helps the environment and costs less.
Disadvantages: proteins often trigger allergies and if at lower temperatures, the pathogens might not all be killed off of your clothes.
How are they used in industry?
Proteases are used to ‘pre-digest’ protein in baby foods.
Carbohydrases are used to convert starch into glucose syrup.
Isomerase is used to covert glucose syrup into fructose syrup which is much sweeter so can be used in smaller qualities in slimming foods.
Advantages and disadvantages of using enzymes.
Advantages: reactions occur faster. Reactions can occur at lower temperatures(saves money). Quite cheep to grow microorganisms.
Disadvantages: can be expensive to extract enzymes. Conditions must be controlled to optimise enzymes activity which can be expensive.
