ACE REVISION KIT
  • Notes
    • Edexcel Science >
      • Biology >
        • B1: The Nature and Variety of Living Organisms
        • B2) Structure and Functions in Living Organisms
        • B3) Reproduction and Inheritance
        • B4) Ecology and the Environment
        • B5) Use of Biological Resources
      • Chemistry >
        • C1) Principles of Chemistry
        • C2) Inorganic Chemistry
        • B3) Physical Chemistry
        • C4) Organic Chemistry
      • Physics >
        • C1) Forces and motion
        • C2) Electricity
        • C3) Waves
        • C4) Energy resources and energy transfers
        • C5) Solids, liquids and gases
        • C6) Magnetism and electromagnetism
        • C7) Radioactivity and particles
        • C8) Astrophysics
    • CIE Mathematics
    • CIE Science >
      • Biology >
        • B0: Keywords
        • B1: Characteristics of Living Organisms
        • B2: Cells
        • B3: Biological Molecules
        • B4: Enzymes
        • B5: Plant Nutrition
        • B6: Animal Nutrition
        • B7: Transport
        • * B8 Diseases and Immunity
        • B9: Gas Exchange and Respiration
        • * B10: Excretion in Humans
        • B11: Coordination and Response
        • * B12: Drugs
        • B13: Reproduction
        • B14: Inheritance
        • B15: Organisms and Their Environment
        • * B16: Biotechnology
        • B17: Human Influences on Ecosystem
        • Biological Drawing
      • Chemistry >
        • C0: Keywords
        • C1: The Particulate Nature of Matter
        • C2: Experimental Techniques
        • C3: Atoms, Elements and Compounds
        • C4: Stoichiometry
        • C5: Electricity and Chemistry
        • * C6: Chemical energetics
        • C7: Energy Changes in Chemical Reactions
        • C8: Chemical reactions
        • C9: Acid, Bases and Salts
        • C10: The Periodic Table
        • C10: Metals
        • C11: Air and Water
        • C13: Sulfur
        • C14: Carbonates
        • C15: Organic Chemistry
      • Physics >
        • P0: Keywords
        • P1: General Physics
        • P3: Thermal Physics
        • P2: Work, Energy, Power
        • P4: Properties of Waves, Light & Sound
        • P5: Electricty and Magnetism
        • P6: Electric Circuits
        • P7: Electromagnetic Effects
        • P8: Atomic Physics
    • iPSLE Science >
      • Diversity
      • Cycles
      • Systems
      • Interactions
      • Energy
      • Type of Exam Qs
  • Past Papers
  • Type of Exam Qs
  • Calculator Techniques
    • Casio fx-96SG PLUS >
      • Solve Simultaneous Equations
      • Solve Quadratic Equation
      • Calculate Statistics
  • Formulas
    • Mathematics
    • Additional Mathematics
    • Physics
  • Contact
1) Describe why Enzymes are important in all living organisms
  • Enzymes are proteins that act as biological catalysts.
  • They are necessary to all living organisms as they maintain the reaction speed of all metabolic reactions at a rate that can sustain life.
2) Explain enzyme action
  • Each enzymes contain an active site, which is a sequence of amino acids with a specific 3-D shape.
  • This shape is complementary to a specific substrate.
  • The substrate enters the active site to form an enzyme-substrate complex.
  • The substrate is broken down and the product is released.
  • The enzyme can then bind to another substrate molecule.​
Picture
source: prenhall
Enzyme actions can be for:
  • ​Catabolic reaction: molecules are broken down.
  • Anabolic reaction: molecules are combined.
3) Explain the Specificity of enzymes
  • The enzyme has a shape called the active site, which exactly fits the substances on which it acts.
  • The shape of the active site of the enzyme molecule and the substrate molecules are complementary.
4) Explain the Effect of changes in Temperature on enzymes activities
  • ​​​Enzymes have an optimum temperature they work best at, giving the fastest reaction, ≈ 37°C in animals.
  • As the temperature increases, molecules have more kinetic energy, so move faster, more successful collisions occur, and more enzyme-substrate complexes can form.
  • At high temperature, enzyme molecules vibrate too vigorously and enzyme become denatured; the active site loses its shape and will no longer bind with a substrate. This decreases the rate of reaction as no enzyme-substrate complexes can form.
  • When low temperature, there is not enough kinetic energy for the reaction so it reacts too slowly.
Picture
source: creative-enzymes
5) Explain the Effect of changes in pH on enzymes activities​
  • Enzymes have an optimum pH that they work best at, some enzymes work best in an acid and others in an alkaline.
  • If the pH moves too far away from the optimum, it can cause the shape of the active site to change, and the enzyme become denatured. This decreases the rate of reaction as no enzyme-substrate complexes can form.​
Picture
source: creative-enzymes
6) Enzymes and their Uses

Seeds to germinate:
  • The enzymes turn insoluble food stores to soluble molecules.

Biological washing powders:
  • Enzymes are added to washing powders to help remove stains for example: lipase for lipids from fatty foods and greasy fingerprints.
  • Protease for proteins from blood stains.

Food industry: 
  • Isomerase converts glucose to fructose which is sweeter, so less is needed to give a sweet taste.
  • Pectinase helps break down cell walls in fruit juice production so it increases yield, lowers viscosity and reduces cloudiness.
Summary

You should know:
  • how enzymes work as biological catalysts
  • about active sites, substrate and products
  • why enzymes are specific for their particular substrates
  • ​how temperature and pH affect enzyme activity
​
​
​​
  • why temperature and pH affect enzyme activity
  • how to investigate the effect of temperature and pH on enzyme activity
  • how to plan and carry out an investigation into enzyme activity
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  • Notes
    • Edexcel Science >
      • Biology >
        • B1: The Nature and Variety of Living Organisms
        • B2) Structure and Functions in Living Organisms
        • B3) Reproduction and Inheritance
        • B4) Ecology and the Environment
        • B5) Use of Biological Resources
      • Chemistry >
        • C1) Principles of Chemistry
        • C2) Inorganic Chemistry
        • B3) Physical Chemistry
        • C4) Organic Chemistry
      • Physics >
        • C1) Forces and motion
        • C2) Electricity
        • C3) Waves
        • C4) Energy resources and energy transfers
        • C5) Solids, liquids and gases
        • C6) Magnetism and electromagnetism
        • C7) Radioactivity and particles
        • C8) Astrophysics
    • CIE Mathematics
    • CIE Science >
      • Biology >
        • B0: Keywords
        • B1: Characteristics of Living Organisms
        • B2: Cells
        • B3: Biological Molecules
        • B4: Enzymes
        • B5: Plant Nutrition
        • B6: Animal Nutrition
        • B7: Transport
        • * B8 Diseases and Immunity
        • B9: Gas Exchange and Respiration
        • * B10: Excretion in Humans
        • B11: Coordination and Response
        • * B12: Drugs
        • B13: Reproduction
        • B14: Inheritance
        • B15: Organisms and Their Environment
        • * B16: Biotechnology
        • B17: Human Influences on Ecosystem
        • Biological Drawing
      • Chemistry >
        • C0: Keywords
        • C1: The Particulate Nature of Matter
        • C2: Experimental Techniques
        • C3: Atoms, Elements and Compounds
        • C4: Stoichiometry
        • C5: Electricity and Chemistry
        • * C6: Chemical energetics
        • C7: Energy Changes in Chemical Reactions
        • C8: Chemical reactions
        • C9: Acid, Bases and Salts
        • C10: The Periodic Table
        • C10: Metals
        • C11: Air and Water
        • C13: Sulfur
        • C14: Carbonates
        • C15: Organic Chemistry
      • Physics >
        • P0: Keywords
        • P1: General Physics
        • P3: Thermal Physics
        • P2: Work, Energy, Power
        • P4: Properties of Waves, Light & Sound
        • P5: Electricty and Magnetism
        • P6: Electric Circuits
        • P7: Electromagnetic Effects
        • P8: Atomic Physics
    • iPSLE Science >
      • Diversity
      • Cycles
      • Systems
      • Interactions
      • Energy
      • Type of Exam Qs
  • Past Papers
  • Type of Exam Qs
  • Calculator Techniques
    • Casio fx-96SG PLUS >
      • Solve Simultaneous Equations
      • Solve Quadratic Equation
      • Calculate Statistics
  • Formulas
    • Mathematics
    • Additional Mathematics
    • Physics
  • Contact