Proteins and Amino acids

Question 1

Define isoelectric point

Answer 1

pH at which a molecule carries no net charge

Question 2

How are aminos able to maintain acid-base balance in mammals?

Answer 2

Conversion to cationic or anionic forms when enviroment becomes more basic or acidic provides balance of pH while amino still remain functional

Question 3

If acid is added to zwitterion solution what molecule will resulting mixture contain?

Answer 3

More of the cationic form to use up the added acid (H+) and stabilise pH

Question 4

Roles of amino acids in metabolism

Answer 4

Synthesis of larger molecules (heme), used as enzymes, signalling and transport molecules

Question 5

pH=pI what form aminos in?

Answer 5

Zwitterion

Question 6

pH

Answer 6

cationic form (NH2 gains H+)

Question 7

pH>pI what form aminos in?

Answer 7

anionic form, (COOH looses H+)

Question 8

What isomerism is most common is biological systems for aminos?

Answer 8

L designation