The Liver, Gall Bladder and Pancreas Flashcards
Where does the liver sit in the body?
Greater part of the right hypochondriac region, part of epigastric and part of the left hypochondriac regions
The appearance of the liver?
The anterior surface is smooth and curved to fit under the diaphragm.
The posterior surface is irregular
Functions of the Liver
Carbohydrate metabolism Fat metabolism Protein metabolism Breakdown of blood cells + micro defence Detoxification of drugs Inactivation of hormones Storage Secretion of bile
How many lobes does the liver have and what are the names?
4 lobes
Right, left, caudate (superiorly), quadrate (inferiorly)
What is the portal fissure and what enters via there?
Portal fissure- is where everything enters the liver. Portal vein Hepatic artery Nerve fibres Lymph ducts Right and left hepatic ducts
Microstructure of the liver?
Made up of lobules-
Hexagonal in outline, formed from cuboidal cells called hepatocytes arrange in pairs of columns radiating from a central vein
Between the columns are sinusoids (blood vessels with incomplete walls)
Macrostructure of the liver?
- Thin inelastic capsule and completely enclosed by a layer of peritoneum
- Held in place by ligaments and the pressure of the other organs
- 4 lobes
- Portal fissue
What are macrophages and what do they do?
Macrophages – Kupffer cells, eat worn out blood cells and foreign particles
What are Bile canaliculi?
Bile canaliculi (small channels) run between the hepatic cells and join up to form larger and larger bile canals until they form the right and left hepatic ducts. The liver secretes bile so it travels through the channels.
Carbohydrate metabolism?
- Maintains plasma glucose levels.
- After a meal, glucose is converted into glycogen
- When glucose levels fall, glycogen is changed back into glucose again.
- All cells need glucose in order to function
Fat Metabolism?
- Some fatty acids and glycerol are used to provide energy and heat.
- Some are combined to form triglycerides, the form in which fat is stored in fat depots i.e. under the skin, around in kidneys and in the omentum
Protein Metabolism?
- Removes the nitrogenous portion from excess amino acids to form urea.
- Combines the nitrogenous portion to other carbohydrate molecules to form new non essential amino acids.
- Breaks down nucleic acids to form uric acid.
- Urea and Uric Acid are excreted in urine.
- Forms 90% of the plasma proteins contained in the blood steam, including albumins, globulins and blood clotting factors
What is the special name for red blood cells?
Erythrocytes
Detoxification and Inactivation of what
Alcohol Waste products from other processes Some drugs Insulin Glucagon Cortisol Aldosterone Thyroid and sex hormones
Storage and Heat role of the liver?
Stores:
- Glycogen
- Fat-soluble vitamins A, D, E, K
- Iron and copper
- Some water-soluble vitamins – e.g. B12
The liver uses lots of energy, high metabolic rate and therefore produces a great amount of heat
Bile- how much and what does it consist of?
500 – 1000ml of bile is secreted by the liver each day. It consists of- Water Mineral salts Mucus Bile pigments, mainly bilirubin Bile salts Cholesterol
Bile in fat digestion?
In the small intestine, the bile acids are secreted as sodium or potassium salts. These emulsify fats by turning them into tiny droplets. More easily absorbed.
Makes fat-soluble vitamins (A,D,E,K) more easily absorbed.
What happens to bile after it is used?
In the terminal ilium, most bile salts are reabsorbed and return to the liver via the portal vein
What is bilirubin?
- Formed by breaking down of old blood cells
- Combined with glucuronic acid to become water-soluble, it is excreted in the bile.
- Microbes in the large intestine convert bilirubin to stercobilin, which colours and deodorizes the stool
- Jaundice is yellow pigmentation of the tissues seen in the skin and conjunctiva, caused by excess blood bilirubin
How does the bile ducts go?
The right and left hepatic duct -> common hepatic duct (portal fissue) -> joined by cystic duct (from gallbladder) - common bile duct -> main pancreatic duct at the hepatopancreatic ampulla -> Ampulla of Vater which is controlled by the hepatopancreatic sphincter (Oddi)
Into the duodenum.
What is the gallbladder?
- Pear-shaped sac attached to the posterior aspect of the liver
- Cover by the peritoneum on its inferior surface only
- Fundus, body, neck
- Supplied by Cystic Artery and drained by the Cystic Vein
The function of the gallbladder?
- Storage of bile
- Hormone CCK (cholecystokinin) – secreted by the duodenum in response to the presence of fat and acid chyme.
- Relaxation of the Sphincter of Oddi and causes the gallbladder to contract (releases the bile).
- Concentration of bile by the absorption of water
Pancreas region?
Epigastric and left hypochondriac regions
Arteries and veins for the pancreas?
Supplied by splenic and mesenteric arteries and drained by splenic and mesenteric veins
Structures that are around the pancreas (head, body, tail)
Head – curve of duodenum
Body -behind the stomach
Tail - in front of left kidney and reaches the spleen.
Aorta and IVC lie behind the gland
Exocrine Pancreas
-Large number of lobules, each drained by a tiny duct
-Unite to form pancreatic duct
Which joins the common bile duct.
-Produces pancreatic juice
-Digestion of carbohydrates, proteins and fats
Endocrine Pancreas
-Throughout the gland are groups of specialised cells – pancreatic islets (Islets of Langerhans)
-No ducts, hormones directly into blood
Insulin and glucagon
The liver weighs between 1 -2.3 kg
Select one:
True
False
True
The majority of the liver sits in the left hypochondriac region
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True
False
False its in the right hypochondriac
The liver sits anterior to the oesophagus
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True
False
True
The liver sits above the right adrenal gland
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True
False
True
The quadrate lobe is the smallest lobe of the liver
Select one:
True
False
False
Its the caudate
The portal fissure is where the blood vessels and nerve fibres enter and leave the liver
Select one:
True
False
True
A blood vessel with an incomplete wall is called a capillary
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True
False
False
its a sinusoid
Cholesterol is found in bile
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True
False
True
Bile is needed to digest protein
Select one:
True
False
False
Jaundice is caused by excess bilirubin
Select one:
True
False
True
Microbes in the large intestine convert Bilirubin to glucuronic acid
Select one:
True
False
False
The cystic duct empties at the Ampulla of Vater
Select one:
True
False
True
The gall bladder is an intraperitoneal structure.
Select one:
True
False
False
The stomach is posterior to the gall bladder
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True
False
True
The gall bladder makes bile
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True
False
False
The pancreas gets some of it blood supply from the splenic artery
Select one:
True
False
True
The pancreas consists of a head, neck and body
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True
False
False
Its head, body, tail
Hepatocytes are cuboidal cells
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True
False
True
Kupffer cells are found in the gall bladder
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True
False
False, they are found in the liver
Vitamin D is stored in the liver
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True
False
True
The common hepatic duct is formed by the right and left hepatic duct and the cystic duct.
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True
False
False
its just the right and left hepatic duct
The pancreas is both an exocrine and endocrine gland
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True
False
True
The Islets of Langerhans produce insulin
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True
False
True