$\mathop {\begin{array}{*{20}{c}}
  {R\,\,\,\,\,\,\,\,\,} \\ 
  {|\,\,\,\,\,\,\,\,\,\,} \\ 
  {{H_2}\ddot N - CH - COOH} 
\end{array}\,}\limits_{\alpha \, - \,amino\,\,acid} $ $\xrightarrow{{In\,\,water}}$

${\begin{array}{*{20}{c}}
  {R\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ 
  {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ 
  {{H_2}\ddot N - CH - CO{O^ - } + {H^ + }} 
\end{array}}$ $\to $ $\underset{\begin{smallmatrix} 
 Zwitter\,\,ion \\ 
 (dipolar\,\,ion) 
\end{smallmatrix}}{\mathop{\begin{matrix}
   \,\,\,\,\,\,\,\,\,\,R\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,  \\
   \,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,  \\
   {{H}_{3}}\ddot{N}-CH-CO{{O}^{-}}  \\
\end{matrix}\,}}\,$

Hence assertion and reason both are true and reson is the correct explanation of assertion.