جامعة بغداد
كلية التمريض
LIVER FUNCTION
Liver:
The liver is in the upper right part of the abdomen. The functions of the liver include: storing glycogen (fuel for the body) which is made from sugars; helping to process fats and proteins from digested food; making proteins that are essential for blood to clot (clotting factors); processing many medicines which you may take; helping to remove poisons and toxins from the body.
The liver also makes bile. This is a greenish-yellow fluid that contains bile acids, bile pigments and waste products such as bilirubin. Liver cells pass bile into bile ducts inside the liver. The bile flows down these ducts into larger and larger ducts, eventually leading to the common bile duct. The gallbladder is like a 'cul-de-sac' reservoir of bile which comes off the common bile duct. After you eat, the gallbladder squeezes bile back into the common bile duct and down into the duodenum (the first part of the gut after the stomach). Bile in the gut helps to digest fats.
Anatomy:
The liver is a reddish brown organ with four lobes of unequal size and shape. A human liver normally weighs between 1.4–1.6 kg (3.1–3.5 lb),[3] and is a soft, pinkish-brown, triangular organ. It is both the largest internal organ (the skin being the largest organ overall) and the largest gland in the human body.
It is located in the right upper quadrant of the abdominal cavity, resting just below the diaphragm. The liver lies to the right of the stomach and overlies the gallbladder. It is connected to two large blood vessels, one called the hepatic artery and one called the portal vein. The hepatic artery carries blood from the aorta whereas the portal vein carries blood containing digested nutrients from the small intestine and the descending colon. These blood vessels subdivide into capillaries which then lead to a lobule. Each lobule is made up of millions of hepatic cells which are the basic metabolic cells.
Lobes:
Traditional gross anatomy divided the liver into four lobes based on surface features. The falciform ligament is visible on the front (anterior side) of the liver. This divides the liver into a left anatomical lobe, and a right anatomical lobe.
If the liver is flipped over, to look at it from behind (the visceral surface), there are two additional lobes between the right and left. These are the caudate lobe (the more superior) and the quadrate lobe (the more inferior).
From behind, the lobes are divided up by the ligamentum venosum and ligamentum teres (anything left of these is the left lobe), the transverse fissure (or porta hepatis) divides the caudate from the quadrate lobe, and the right sagittal fossa, which the inferior vena cava runs over, separates these two lobes from the right lobe.
Each of the lobes is made up of lobules; a vein goes from the centre of each lobule which then joins to the hepatic vein to carry blood out from the liver.
On the surface of the lobules there are ducts, veins and arteries that carry fluids to and from them.
Function:
The central area where the common bile duct, hepatic portal vein, and hepatic artery proper enter is the hilum or "porta hepatis". The duct, vein, and artery divide into left and right branches, and the portions of the liver supplied by these branches constitute the functional left and right lobes.
The functional lobes are separated by an imaginary plane joining the gallbladder fossa to the inferior vena cava. The plane separates the liver into the true right and left lobes. The middle hepatic vein also demarcates the true right and left lobes. The right lobe is further divided into an anterior and posterior segment by the right hepatic vein. The left lobe is divided into the medial and lateral segments by the left hepatic vein. The fissure for the ligamentum teres also separates the medial and lateral segments. The medial segment is also called the quadrate lobe. In the widely used Couinaud (or "French") system, the functional lobes are further divided into a total of eight subsegments based on a transverse plane through the bifurcation of the main portal vein. The caudate lobe is a separate structure which receives blood flow from both the right- and left-sided vascular branches.
Other functions:
1. The liver stores a multitude of substances, including glucose (in the form of glycogen), vitamin A (1–2 years' supply), vitamin D (1–4 months' supply), vitamin B12 (1-3 years' supply), iron, and copper.
2. The liver is responsible for immunological effects- the reticule endothelial system of the liver contains many immunologically active cells, acting as a 'sieve' for antigens carried to it via the portal system.
3. The liver produces albumin, the major osmolar component of blood serum.
4. The liver synthesizes angiotensinogen, a hormone that is responsible for raising the blood pressure when activated by rennin, an enzyme that is released when the kidney senses low blood pressure.
كلية التمريض
LIVER FUNCTION
Liver:
The liver is in the upper right part of the abdomen. The functions of the liver include: storing glycogen (fuel for the body) which is made from sugars; helping to process fats and proteins from digested food; making proteins that are essential for blood to clot (clotting factors); processing many medicines which you may take; helping to remove poisons and toxins from the body.
The liver also makes bile. This is a greenish-yellow fluid that contains bile acids, bile pigments and waste products such as bilirubin. Liver cells pass bile into bile ducts inside the liver. The bile flows down these ducts into larger and larger ducts, eventually leading to the common bile duct. The gallbladder is like a 'cul-de-sac' reservoir of bile which comes off the common bile duct. After you eat, the gallbladder squeezes bile back into the common bile duct and down into the duodenum (the first part of the gut after the stomach). Bile in the gut helps to digest fats.
Anatomy:
The liver is a reddish brown organ with four lobes of unequal size and shape. A human liver normally weighs between 1.4–1.6 kg (3.1–3.5 lb),[3] and is a soft, pinkish-brown, triangular organ. It is both the largest internal organ (the skin being the largest organ overall) and the largest gland in the human body.
It is located in the right upper quadrant of the abdominal cavity, resting just below the diaphragm. The liver lies to the right of the stomach and overlies the gallbladder. It is connected to two large blood vessels, one called the hepatic artery and one called the portal vein. The hepatic artery carries blood from the aorta whereas the portal vein carries blood containing digested nutrients from the small intestine and the descending colon. These blood vessels subdivide into capillaries which then lead to a lobule. Each lobule is made up of millions of hepatic cells which are the basic metabolic cells.
Lobes:
Traditional gross anatomy divided the liver into four lobes based on surface features. The falciform ligament is visible on the front (anterior side) of the liver. This divides the liver into a left anatomical lobe, and a right anatomical lobe.
If the liver is flipped over, to look at it from behind (the visceral surface), there are two additional lobes between the right and left. These are the caudate lobe (the more superior) and the quadrate lobe (the more inferior).
From behind, the lobes are divided up by the ligamentum venosum and ligamentum teres (anything left of these is the left lobe), the transverse fissure (or porta hepatis) divides the caudate from the quadrate lobe, and the right sagittal fossa, which the inferior vena cava runs over, separates these two lobes from the right lobe.
Each of the lobes is made up of lobules; a vein goes from the centre of each lobule which then joins to the hepatic vein to carry blood out from the liver.
On the surface of the lobules there are ducts, veins and arteries that carry fluids to and from them.
Function:
The central area where the common bile duct, hepatic portal vein, and hepatic artery proper enter is the hilum or "porta hepatis". The duct, vein, and artery divide into left and right branches, and the portions of the liver supplied by these branches constitute the functional left and right lobes.
The functional lobes are separated by an imaginary plane joining the gallbladder fossa to the inferior vena cava. The plane separates the liver into the true right and left lobes. The middle hepatic vein also demarcates the true right and left lobes. The right lobe is further divided into an anterior and posterior segment by the right hepatic vein. The left lobe is divided into the medial and lateral segments by the left hepatic vein. The fissure for the ligamentum teres also separates the medial and lateral segments. The medial segment is also called the quadrate lobe. In the widely used Couinaud (or "French") system, the functional lobes are further divided into a total of eight subsegments based on a transverse plane through the bifurcation of the main portal vein. The caudate lobe is a separate structure which receives blood flow from both the right- and left-sided vascular branches.
Other functions:
1. The liver stores a multitude of substances, including glucose (in the form of glycogen), vitamin A (1–2 years' supply), vitamin D (1–4 months' supply), vitamin B12 (1-3 years' supply), iron, and copper.
2. The liver is responsible for immunological effects- the reticule endothelial system of the liver contains many immunologically active cells, acting as a 'sieve' for antigens carried to it via the portal system.
3. The liver produces albumin, the major osmolar component of blood serum.
4. The liver synthesizes angiotensinogen, a hormone that is responsible for raising the blood pressure when activated by rennin, an enzyme that is released when the kidney senses low blood pressure.
