Amino acids have both an amino group and a carboxyl group in their structure. Which amongst the following is an amino acid?
1. Formic acid
2. Glycerol
3. Glycolic acid
4. Glycine
An amino acid under certain conditions has both positive and negative charges simultaneously in the same molecule. Such a form of amino acid is called
1. acidic form
2. basic form
3. aromatic form
4. zwitterionic form