• Pancreas…

Pancreas is a gland of gray and pink color. Its length is 6 to 9 inches. Its weight is around 60 grams. It is located in the abdominal cavity. Its shape is fish-shaped with its head and neck found in the C-shaped curved part of the duodenum. Its body part extends horizontally to the spleen and its tail part touches the part of the spleen. Posterior to the pancreas are the abdominal aorta and the inferior vena cava.

Pancreas gland functions in both exocrine and endocrine ways.

Exocrine Pancreas..

This part of the exocrine pancreas is made up of many lobules. Within these lobules are secretory cells. These secretory cells release their secretion into small ducts and these small ducts join to form a large duct called pancreatic duct. It carries the secretions of the pancreas to the small intestine.

The pancreatic duct joins the common bile duct from the liver and gall bladder and opens into the duodenum of the small intestine through the hepatopancreatic ampulla and drains the secretions there. The hepatopancreatic ampulla is flanked by sphincter muscles that control the flow of secretions. This sphincter muscle is also known as sphincter of Audi.

The exocrine part of the pancreas secretes pancreatic juice which helps in the digestion and absorption of carbohydrates, fats and proteins.

Endocrine Pancreas..

One percent of the total cells within the pancreas function as the endocrine pancreas. Which are arranged in a tangle and these bunches are also known as pancreatic islets or islets of Langer Hans which are known as alpha, beta and delta cells.

These cells within the pancreas secrete hormones that secrete glucagon, insulin, and somatostatin hormones, respectively. This part of the pancreas functions as an endocrine pancreas. This hormone maintains blood glucose levels in the body.

Pancreas secretes hormones that perform endocrine functions.

The pancreas secretes juices that help in the digestion of proteins, fats and carbohydrates.

Thus the pancreas performs both endocrine as well as exocrine functions.

• Liver…

Among all the glands in the body, the liver is the largest gland.which lies below the diaphragm in the right quadrant of the abdominal cavity. It weighs approximately 1.4 kilograms inside an adult. It lies below the ribs of the chest. Ribs protect it. A part of it is also located in the region of the left abdominal cavity.

The upper surface of the liver is smooth. This portion is attached to the diaphragm and has an irregular surface and margin on the back and underside of the liver.

Organs around the liver.

Organs such as the diaphragm, anterior abdominal wall muscles, stomach, duodenum, kidney, inferior vena cava, gallbladder etc. are arranged around the liver.

Liver is mainly divided into two lobes, right lobe and left lobe.

The right lobe is larger than the left lobe and both lobes are separated by the falciform ligament.

The quadrate lobe is found on the posterior side of the liver and the quadrate lobe is found on its inferior side.

Thus four lobes of liver can be seen anatomically.

Portal Fissure…

The groove on the posterior surface of the liver is called the portal fissure. From this fissure some structures enter the liver and some structures exit the liver viz.

The portal vein carries deoxygenated and nutritious blood from the intestine and enters the liver through this fissure.

The hepatic artery carries oxygenated blood and enters the liver through this fissure.

Nerve fibers of the sympathetic and parasympathetic nerves enter the liver through this fissure.

Left and right hepatic ducts exit this fissure to carry bile from the liver to the gall bladder.

The hepatic vein exits this fissure to carry deoxygenated blood from the liver.

Structure of the Liver…

The liver is an organ located in the right quadrant of the abdominal cavity. It is mainly composed of 2 lobes.These lobes are made up of many lobules. These lobules are made up of special type of epithelium cells and cells called hepatocytes. These cells are found in a hexagonal pattern in the liver.

After entering the hepatic artery and portal vein within the liver, a capillary network of arteries and veins is formed. This network of capillaries is called sinusoids. Kupffer cells are found in the wall of these sinusoids, which Kupffer cells act to protect the liver from bacteria, foreign material or toxins and perform a protective function in the liver.

Hepatocytes cells within the liver secrete bile.This bile enters the bile canaliculi. These bile canaliculi carry the bile into small bile ducts. These small bile ducts join to form the right and left hepatic ducts. which drains bile from the liver through the common hepatic duct. The common hepatic duct joins with the cystic duct from the anterior gallbladder to form the common bile duct. Bile is drained into the small interstitium and plays an important role in the digestion of fat.

Blood supply of the liver.

The liver is supplied with blood by the hepatic artery and the portal vein carries nutritious blood and enters the liver.

The hepatic vein drains deoxygenated blood from the liver and joins the inferior vena cava.

Functions of the Liver..

Liver is a very important organ of our body. It is associated with many important functions.These functions are as follows.

The liver is responsible for the metabolism of carbohydrates.

The liver functions to maintain normal carbohydrate ie blood glucose levels. When the blood glucose level decreases, glucose is made from glycogen through the action of glycogenolysis and blood glucose level is maintained.

When the amount of glucose in the blood increases, glucose is converted into glycogen by the action of glycogenesis.

The liver converts fat into fatty acids so that it can be used in the body, this is called desaturation of fat, thus it helps in lipid metabolism.

The liver helps in protein metabolism so that amino acids are synthesized in the body.

The liver converts ammonia and makes urea so that this waste product can be excreted through urine.

The death of red blood cells releases bilirubin, which is modified by the liver to help remove excess bilirubin from the body.

Liver helps to detoxify the toxic substances, alcohol, drugs etc. introduced in the body and remove them from the body.

The liver synthesizes bile salts, which are essential for emulsification of fats and hence absorption of lipids and cholesterol.

Helps to maintain the level of vitamin D in the body.

Since Kupffer cells are located inside the liver, they perform a protective function by protecting the liver from harmful substances and performing phagocytosis.

The liver acts as a storage of vitamins and minerals and releases these vitamins and minerals into the body when needed.

Liver is responsible for heat production in the body.

Composition of Bile…

The liver is responsible for secreting bile. It secretes approximately 500ml of bile during the day.

The structure of this bile contains water, mineral salts, mucus, bile pigments, bile salts, cholesterol etc.

Bile is a yellow liquid. It also has brown or olive green type characteristics. Its pH is 7.6 to 8.6 i.e. it has alkali ph.

Bile helps in the emulsification of fat i.e. it helps in converting its larger molecules into smaller molecules.

Bilirubin in the bile pigment is its main component and the breakdown of bilirubin produces stercobilin which is brown in color and is excreted through the stool.

• Goalblader…

Goalbladder is a pear-shaped shake.It is located on the posterior side of the liver in the abdominal cavity. It is 7 to 10 cm long and 3 cm wide. It has a capacity to store 30 to 50 ml of bile.It is connected by areolar connective tissue.

Structure of the Gallbladder…

Goalbladder is divided into three parts.

fundus

the body

and the neck.

There are three tissue layers around it.

At the outermost side is the serous peritoneal layer.

The middle layer is made up of unstriped type muscles with oblique muscle fibres.

On the innermost side there is a layer of mucus membrane.This layer is also continuous with the inner lining of the ducts leading from the gallbladder.

The inner lining of this mucus membrane is composed of columnar epithelium cells. which secretes mucin and rapidly absorbs water and electrolytes but does not absorb bile salts and bile pigments so that bile becomes concentrated and bile decreases.

The cystic duct that carries bile from the gallbladder is 4 cm long. which joins the common hepatic duct from the liver and forms the common bile duct which carries bile to the duodenum of the small intestine.

Blood supply to the gallbladder is via the hepatic and splenic arteries and venous return via its venous branch.

It is nerve supplied by sympathetic and parasympathetic nerve fibers.

Functions of the Goalbladder..

Gallbladder acts as a bag to store bile.

Gallbladder releases bile as needed into small interstitial spaces which aid in digestion.

• Metabolism…

Metabolism means metabolism. It is a chemical reaction of the body in which ATP is transported in the living cells of the body.

Metabolism involves two types of processes.

1. Catabolism is the chemical process of converting complex molecules into simple molecules. In which energy is released in the form of ATP. For example the conversion of glycogen to glucose. Conversion of proteins to amino acids.
2. Anabolism is a type of chemical reaction in which simple and small molecules combine to form complex molecules or larger molecules. This process requires ATP. Like formation of glycogen from glucose.