questions

• what do veins do?

  • carry blood away from your organs and away from your heart
  • blood is usually low in oxygen
• what do arteries do?

  • carry blood away from the heart to the organs
  • stretch as blood forces through which is felt as a pulse
• what are enzymes?

  • biological catalysts that speed up reactions
  • have a special region called active sites
  • active site has a specific shape which fits the substrate
• what are the four components of blood?

  • red blood cell
  • white blood cell
  • plasma
  • platelets
• what test is used to test for proteins?

  • biuret reagent
  • if proteins are present, there is a colour change from blue to lilac
• what test is used to test for sugars?

  • benedict's solution
  • if sugar is present, there is a colour change from blue to green/yellow if a low amount is present and red if it is high
• what test is used to test for starch?

  • iodine solution
  • if starch is present, there is a colour change from yellow/brown to blue/black