Question

estion 1 Describe the three phases of energy metabolism, their function, and their regulation by pancreatic hormones.

Answer 1

There are 3 phases of Energy Metabolism
1) Cephalic Phase
2) Digestive Phase, and
3) Adsorption Phase

Cephalic Phase: During this phase of energy metabolism Insulin is releases due to sight, smell and thought of food. This process is controlled by brain.

Digestive Phase: During digestive phase food makes entry into the gut. In response to high fat or protein content in stomach insulin got secreted in gut and when food reaches the gut CCK gut hormones activates and stimulates release of above secreted insulin into the gut.

Adsorptive Phase: In this nutrients got adsorped into the cells and used up for immediate energy requirement. Remaining glucose and other things are stored for future use. At this time glucose level increases in blood stream and this increased level of glucoses stimulates pancrease gland and live glucodetector and causes direct insulin secretion and release into the blood. this insulin takes up glucose molecules from blood stream to cell for their work. where this glucose molucules produces energy and uses it for various processes..

You can see in all 3 phases you will find release of insulin which takes up glucose and transfers to cell for energy production. Hence during this 3 phases insulin level will be high and glucose level will be low.

Functions of pancreatic hormones:
Pancrease secretes and discharges digestive enzymes into the gut and also secretes carbohydrates metabolising hormones . so, it helps in digestion process and also helps in energy metabolism.
It also helps in maintaining salt balance.
various primary pancreatic hormones secreted by pancrease are
Gastrin, somatostatin, Vasoactive intestinal peptide, insulin and glucagon..

Regulation of energy metabolism by Pancreatic hormones:
Two pancreatic hormones are involved in carbohydrates metabolism (energy metabolism )and its regulation.
They are Insulin and Glucagon.

Insulin and glucagon both are secreted in response to glucose levels in blood . Glucagon is counter regulatory hormone to insulin.
Insulin is secreted when in response to food stimulation, high glucose levels and it helps in glucose take up to cell from blood stream. where as glucagon is secreted when glucose levels are down in blood stream. Gucagon helps in bringing back glucose level to normal in blood stream. it acts on liver where it converts stored glycogen to glucose. This glucose is secreted innto the blood stream and hence blood glucose levels comes to normal.

In this way glucose levels and metabolism are regulated by two pancreatic hormones.