Question

A functional group on an amino acid that is polar and can become positively charged: ___________

Answer 1

The polar functional group that can become positively charged on an amino acid is typically found in basic amino acids like lysine and arginine.

Step-by-step explanation:

The functional group on an amino acid that is polar and can become positively charged is often found in basic amino acids. Basic amino acids such as lysine and arginine have side chains that contain a positive charge under physiological conditions. These amino acids are essential in the structure and biological activity of proteins. For example, in the classification of amino acids, those like lysine (Lys) and arginine (Arg) are recognized for the basic groups in their side chains which can participate in hydrogen bonding and other important biochemical interactions.

The functional group on an amino acid that is polar and can become positively charged is the amino group (-NH2). This group contains a nitrogen atom, which can accept a hydrogen ion (H+) to form a positively charged ammonium group (-NH3+). Amino acids that have an amino group in their side chain, such as lysine and arginine, are considered basic amino acids because they can donate a proton and become positively charged.

Answer 2

Amino group (NH3)

Step-by-step explanation:

The amino acids have a central carbon atom to which four functional groups are bonded. These are namely a carboxyl group (COOH), an amino group (NH3), a hydrogen atom and an R group (it varies for different amino acids).

Amino group (NH3) is common to all the standard 20 amino acids. NH3 is a polar group since higher electronegativity of nitrogen atom allows it to pull the shared electrons of the covalent bonds towards itself. It makes the nitrogen atom of amino group partially negative and the hydrogen atoms carry a partial positive charge (a dipole is present).

Amino group (NH3) accepts one proton and becomes positively charged (NH4+).