Bio - cells and biological functions

• What chemical elements are present in carbohydrates?

  • carbon
  • hydrogen
  • oxygen
• What chemical elements are present in lipids?

  • carbon
  • hydrogen
  • oxygen
• What chemical elements are present in protein?

  • Carbon
  • hydrogen
  • oxygen
  • sulfur
  • nitrogen
• What are complex carbohydrates like starch and glucose made up of ?

  • simple sugars
• what are proteins made up of?

  • amino acids
• What two molecules are lipids made up of

  - fatty acid tails

  • glycerol
• What are enzymes?


  Enzymes are biological catalysts which increase the rate of reactions
• State 4 factors that affect enzyme function?

  1. temperature
  2. ph
  3. substrate concentration
  4. enzyme concentration
• Describe the effect of temperature on the rate of an enzyme controlled reaction?

  • as temperature increases, so does rate of reaction
  • if the temperature exceeds optimum, the enzyme denatures and rate of reaction decreases
• Why does the rate of an enzyme-controlled reaction increase when the temperature increases?

  • as temoerature increases, kinetic energy also increases within particles
  • this makes particle collision more frequent which result in a successful reaction
• What is diffusion?


  Diffusion is the movement of particles from an area of high concentration to an area of low concentration down their concentration gradient.
• How does temperature affect the rate of diffusion?

  • Temperature affects the rate of diffusion by increasing the kinetic energy of particles,
  • causing them to move faster and collide more frequently,
  • which results in a faster rate of diffusion.
• How does the concentration gradient affect the rate of diffusion?

  • the greater the concentration gradient (the difference between the two areas)
  • the faster the rate of diffusion
• How does the surface area of the membrane affect the rate of diffusion?

  • A larger surface area allows for more molecules to pass through the membraneincreasing the rate of diffusion.
• What is osmosis?

  • the movement of water particles from high concentration to low concentration down the water potential gradient across a partially permeable membrane
• What is active transport?

  • the movement of molecules from low concentration to a high concentration against their concentration gradient using energy