ALBUMIN EXPERIMENT

Albumin Experiment

Albumin Experiment

Aim:

To investigate effect of temperature on time taken for pepsin to digest egg albumen.

Prediction:

The higher temperature quicker time take for digestion, but once temperatures above 40 degrees are reached reaction will slow down again.

Hypothesis:

Enzymes are biological catalysts made up from protein. As we know, catalysts are substances that speed up rate of the reaction without itself being used up. One type of enzyme will only catalyze one type of reaction. (Sheffner & Eckfeldt 1956: 4)

An enzyme has an 'active site, which has the unique shape, which only the substrate of same shape can fit into, like the key and the padlock. A digestive enzyme helps digestion by breaking down large insoluble molecules into small soluble molecules for absorption into blood stream for uses within body. Different groups of enzymes are responsible for digesting different types of food substances. (Northrop 2000 : 21) The enzyme pepsin is part of protease 'family' of enzymes that have job of breaking down protein molecules into smaller amino acids for repair and growth of cells in body. Enzymes can become denatured in extreme heat conditions or in unfavorable pH conditions.

The bonds in enzymes are weak, thus when above stated conditions are reached bonds are broken, deforming enzyme and its active site, and it will no longer act as the catalyst properly anymore(Ma 1996: 12).

Apparatus:

5cm cubed egg albumen

5cm cubed pepsin 5%

2 drops of: HCl 2M

Test tubes

Pipette

Stopwatch

Universal Indicator Paper

Measuring cylinder

Diagram:

Method:

Measure out 5cm squared of egg albumen in the measuring cylinder, and then 5cm squared of pepsin 5% separately. Heat them both individually for 2 to 3 minutes at desired temperature water baths, which should be electronic so as to keep consistent temperature. For 20 ...