(N/A) Digestion of fats:
Butter is a fat product and is primarily digested in the small intestine. The bile juice secreted by the liver contains bile salts that break down large fat globules into smaller globules to increase their surface area for the action of lipase. This process is known as emulsification of fats.
Following this,pancreatic lipase from the pancreatic juice and intestinal lipase from the intestinal juice hydrolyze the fat molecules into triglycerides,diglycerides,monoglycerides,and ultimately into fatty acids and glycerol.
$Fats \xrightarrow{\text{Pancreatic lipase}} \text{Triglycerides} + \text{Diglycerides}$
$\text{Diglycerides and monoglycerides} \xrightarrow{\text{Lipases}} \text{Fatty acids} + \text{Glycerol}$
Absorption of fats:
Fat absorption is a complex process. Since fatty acids and glycerol are water-insoluble,they cannot be directly absorbed into the blood. They are first incorporated into small,spherical droplets called micelles,which transport them to the intestinal mucosa.
In the intestinal cells,they are reformed into small,protein-coated fat globules called chylomicrons. These chylomicrons are transported into the lymph vessels (lacteals) in the villi. From the lymph,the absorbed fats are finally released into the bloodstream to be distributed to the cells of the body.