Site author Richard Steane
The BioTopics website gives access to interactive resource material, developed to support the learning and teaching of Biology at a variety of levels.

Examples of enzymes and their action

  • substrate(s) -enzyme- product(s)

Carbohydrases (enzymes acting on carbohydrates)

  • starch (+ water) -amylase- maltose
  • maltose (+ water) -maltase- glucose + glucose
  • sucrose (+ water) -sucrase (invertase)- glucose + fructose

  • lactose (+ water) -lactase (beta-galactosidase)- glucose + galactose
  • Lactase may also be known as beta-galactosidase

Proteases (enzymes acting on proteins)

  • proteins (+ water) -pepsin- polypeptides
  • liquid milk proteins (+ water) -rennin- coagulated milk solids

Lipases (enzymes acting on lipids)

  • fats/oils (+ water) -lipase- fatty acids + glycerol

Other (non-digestive) enzymes

  • hydrogen peroxide -catalase- water + oxygen

Measuring rate of reaction of enzyme-controlled reactions

    This may be achieved by directly measuring
  • appearance of product over time
  • disappearance of substrate over time.

From these measurements rate of reaction may be directly calculated.

Alternatively, using the time T taken for the reaction to reach a certain stage:
Rate of reaction prop to 1/T ( rate is inversely proportional to T)

Actually it may be easier to use 100/T or 1000/T (just to avoid excess decimal places).
Make sure you are measuring T in a consistent manner (e.g. all in seconds, or minutes [convert min:sec to decimal minutes so 2:30 becomes 2.5 min])

To return to the original page, please click on the browser "return" button

If you came here via an external link, you may click on these icons as links to jump to the top of this page, or to go either to the contents page - a full listing of educational topics on this website - or to the front index page.

Close this window? Another look? Return to the contents page? Back to the BioTopics index page?

www.BioTopics.co.ukHome Contents Contact via form Contact via email Howlers Books WWWlinks Terms of use Privacy