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enzymes

EsraaAbdelMagid

How pH affects enzyme activity? And what does pH means in the first place?

Reply 1

Lighfy

Original post by EsraaAbdelMagid

How pH affects enzyme activity? And what does pH means in the first place?

Enzymes have an optimum pH at which they work best at. For example, the enzymes in your stomach have an optimum pH of around 2, as your stomach is acidic in order to break down complex molecules. If the pH is altered then the active site of an enzyme will also be altered, due to changes in its tertiary structure. This means that substrates will not be complementary to the active site and so the enzymes will become ineffective.

pH itself refers to how acidic or alkaline something is. A pH of 1-6 indicates that it is either a strong/weak acid. 7 is a neutral pH, and 8-14 indicates a strong/weak alkali. Mathematically you can calculate pH with the expression:

pH = -log[H+]

Although you probably won't need to know this if you don't do A-level Chemistry.

Hope this helps.

Reply 2

EsraaAbdelMagid

Thanks