Why the ph of glycine increases when 0.1 M NaOH is added dropwise​

The acid-base reaction produces glycine reduction, and hence the increase of glycine pH.

Explanation:

The glycine is an amino acid with the following chemical formula:

NH₂CH₂COOH  

The COOH functional group is what gives the acid properties in the molecule.      

Hence, when NaOH is added to glycine an acid-base reaction takes place in which COOH reacts with the NaOH added:

NH₂CH₂COOH + OH⁻ ⇄ NH₂CH₂COO⁻ + H₂O

The glycine concentration starts to shift to its ion form (NH₂CH₂COO⁻) because of the reaction with NaOH, that is why the pH glycine increases when NaOH is added.  

Therefore, the acid-base reaction produces glycine reduction, and hence the increase of glycine pH.  

I hope it helps you!