A biological catalyst that increases the rate of a specific reaction without being used up or changed.
They can join or split particles, depending on their role.
They are made from protein.
They turn substrate molecules into product molecules.
1 of 9
The speed they work at depends on...
Temperature: when it's warmer particles have more energy so move faster, resulting in more energetic and more frequent collisions with the substrate molecules. When it gets too hot, enzymes can become denatured.
pH: this can interfere with bonds and denature the enzymes
2 of 9
They are used in different human processes:
Digestion: breaking down complex molecules into simpler ones that can be absorbed into the bloodstream.
Protein sythesis: joining amino acids together in a specific order.
Respiration: enzymes in mitochodria increase the rate of respiration.
3 of 9
What is this energy used for?
Building large molecules from smaller ones
Muscle contractions for movement
Maintaining a constant body temperature
(PLANTS) Building amino acids from sugars and nitrates
4 of 9
Digestion
Enzymes break down big molecules that can't diffuse through the cell membrane into smaller molecules that can:
Starch -> Amylase -> Simple sugars
Salivary gland
Pancreas
Small intestine
Protein -> Protease -> Amino acids
Stomach
Pancreas
Small intestine
Lipids -> Lipase -> Glycerol and Fatty Acids
Pancrease
Small Intestine
5 of 9
The role of bile
Produced in the liver
Stored in the gall bladder
Released into the small intestine
Neutralises stomach acid to allow enzymes in the small intestine to work at an optimum, without becoming denatured
Emulsifies fats, breaking them into smaller particles which gives them a larger surface area. This increases the number of collisions and allows them to be broken down quicker by lipase.
6 of 9
Other Information about Digestion
Hydrochloric acid kills bacteria in the stomach
Rectum stores faeces
Small intestine absorbs food
Large intesting absorbs water
7 of 9
Enzymes in Industry
Baby food: protease digests protein so it's easier for babies to digest.
Sugar: carbohydrases break down starch into sugar, which is cheaper that sugar.
Slimming food: Isomerase turns glucose into fructose which is sweeter so less needs to be used, resulting in fewer calories.
Biological detergents: digest fats and proteins in stains on clothes
8 of 9
Advantages and Disadvantages of Enzymes in Industr
Specific: only catalyse the reaction you want
Lower temperature: lower costs, less energy used
Long-lasting: not used up, spreads costs over a long time
Biodegradable: less pollution
People can be allergic to enzymes
Easily denatured: expensive to control the conditions
Enzymes can be contaminated, affecting the reaction
Comments
No comments have yet been made