In the pancreas,the secretion of pancreatic juice and hormones is performed by:

The pancreas secretes:

Beta and alpha cells secrete the following hormones in respective order:

The hormone glucagon causes ......... .

$A$ sample of urine was diagnosed to contain a high content of glucose and ketone bodies. Based on this observation, answer the following:
$(a)$ Which endocrine gland and hormone is related to this condition?
$(b)$ Name the cells on which this hormone acts.
$(c)$ What is the condition called and how can it be rectified?

Treatment with alloxan destroys: