$(a)$ Name one organ each where growth hormone is synthesized in man and plant.
$(b)$ List the sequence of events that occur when a plant is exposed to unidirectional light,leading to bending of a growing shoot. Also,name the hormone and the type of movement.

(N/A) In humans,growth hormone is synthesized in the anterior lobe of the $Pituitary$ $gland$. In plants,growth hormones (auxins) are synthesized in the shoot tips (apical meristems).
$(b)$ The sequence of events is as follows:
$1$. When a plant is exposed to unidirectional light,the hormone $Auxin$ is synthesized at the shoot tip.
$2$. $Auxin$ diffuses towards the shaded side of the shoot,away from the light source.
$3$. The higher concentration of $Auxin$ on the shaded side stimulates the cells to elongate more rapidly compared to the cells on the illuminated side.
$4$. This differential growth causes the shoot to bend towards the light source.
$Name$ $of$ $the$ $hormone$: $Auxin$.
$Type$ $of$ $movement$: $Phototropic$ $movement$ (or $Phototropism$).