Biomolecules in the Cell > Proteins - Classification of Amino Acids

Amino acids are the building blocks of ____________.

Give a reason for the following observations:

Amino acids behave like salts.

Define the following term as related to proteins:

Primary structure

How do you explain the amphoteric behaviour of amino acids?

The functional group which is found in amino acids is:

Amino acids are classified as acidic, basic or neutral depending upon the relative number of amino and carboxyl groups in their molecule. Which of the following are acidic?

(i)

\[\begin{array}{cc}
\ce{(CH3)2CH - CH - COOH}\\
\phantom{..}|\\
\phantom{.....}\ce{NH2}
\end{array}\]

(ii)

\[\begin{array}{cc}
\ce{HOOC - CH2 - CH2 - CH - COOH}\\
\phantom{............}|\\
\phantom{...............}\ce{NH2}
\end{array}\]

(iii)

\[\ce{H2N - CH2 - CH2 - CH2 - COOH}\]

(iv)

\[\begin{array}{cc}
\ce{HOOC - CH2 - CH - COOH}\\
\phantom{.....}|\\
\phantom{........}\ce{NH2}
\end{array}\]

Assertion: Glycine must be taken through diet.

Reason: It is an essential amino acid.

Draw the zwitter ion structure for sulphanilic acid.