Adrenal medulla secretes two hormones called adrenaline or epinephrine and noradrenaline or norepinephrine (also called emergency hormones).

Both the hormones -

$\bullet$ Cause pupillary dilation (not constriction)

$\bullet$ Stimulate breakdown of glycogen resulting in increased concentration of glucose in blood i.e., cause hyperglycemia.

$\bullet$ Cause piloerection (raising of hair).

$\bullet$ Increase strength of heart contraction i.e. heartbeat.