Digestive Roles of Liver and Pancreas

The liver is the largest gland in the human body and carries out a variety of functions which are essential for digestion and overall metabolism.
One of its primary roles is the production of bile, a green-yellow fluid that aids in the digestion of fats.
Bile is made up of bile salts, cholesterol, bilirubin, sodium, potassium, and other elements. Of these, bile salts are the most important for digestion as they help to emulsify dietary fat, breaking it down into smaller droplets thus making it more accessible to enzymes.
After synthesis in the liver, bile is stored and concentrated in the gallbladder until it is needed for digestion.
Upon consumption of a meal, bile is released into the duodenum (the first part of the small intestine), where it neutralises stomach acid and prepares fats and oils for digestion.
The liver also plays a role in the regulation of blood glucose levels. It does this by storing excess glucose as glycogen and releasing it back into the blood when required, a process known as glycogenolysis.
Moreover, the liver processes and detoxifies various substances including alcohol and drugs, and removes waste products like ammonia from the blood, converting it into urea which is excreted in the urine.

The pancreas is a small organ located behind the stomach and plays a significant role in both digestion and hormone production.
It generates a juice rich in a wide array of digestive enzymes that are delivered to the duodenum. These enzymes help in the breakdown of proteins, fats, and carbohydrates, continuing the process of digestion which started in the stomach.
Among these enzymes are trypsin and chymotrypsin (for protein digestion), pancreatic lipase (for fat digestion), and pancreatic amylase (for carbohydrate digestion).
The pancreas also produces bicarbonate ions which are released into the duodenum along with the digestive enzymes. These bicarbonate ions neutralize the acidic chyme (partially digested food) from the stomach, creating a buffered alkaline environment which favours the action of the pancreatic enzymes.
Besides its exocrine functions (those related to digestion), the pancreas has endocrine functions - it produces insulin and glucagon, key hormones which regulate blood glucose levels.