Define the following terms:
$1.$ Chasmogamous
$2.$ Cleistogamous

(N/A) $1.$ Chasmogamous flowers are flowers that open and expose their anthers and stigmas to the environment,allowing for cross-pollination. Examples include $Viola$,$Oxalis$,and $Commelina$.
$2.$ Cleistogamous flowers are flowers that do not open at all. In these flowers,the anthers and stigmas lie close to each other,ensuring self-pollination (autogamy) even in the absence of pollinators. Examples include $Viola$,$Oxalis$,and $Commelina$.