Functions of the Pancreas Flashcards
What is the nutrient associated with the mouth?
Carbohydrates
What is the enzyme that breaks down carbohydrates? What is its action like?
Salaivary Amylase. begins the digestion in the stomach
What is the nutrient associated with the stomach?
Protein
What is the enzyme of the stomach, and what is its action?
Denatures protein
What are the nutrients associated with the pancreas?
Lipid
Carbohydrate
Protein
What are the enzymes of the pancreas? (6)
Pepsin
Gastric lipase
Pancreatic amylase
Trypsinogen
Chymotrypsinogen
Procarboxypeptidase
What is trypsinogen converted into?
Trypsin
What is chymotrypsinogen converted into?
Chymotrypsin
What is procarboxypeptidase converted into?
Carboxypeptidase
What is the function of pepsin?
Begins the hydrolysis of polypetides
What is the function of gastric lipase?
Begins digestion of lipids
What is the function of the pancreatic amylase?
Digestion of starch
What is the function of trypsin?
An enzyme that is activated in the small intestine that catalyzes the hydrolysis of proteins to form smaller polypeptide units
What is the function of of chymotrypsin?
A protein enzyme activated in the small intestine that catlyzes the hydrolysis of proteins into polypeptides and amino acids
What is the function of carboxypeptidase?
A protein enzyme that hydrolyzes the carboxy end of a peptide release the last amino acid in the peptide chain
What are the nutrients of the small intestine?
Lipid
Carbohydrate
Protein
What are the enzymes of the small intestine?
Pancraetic lipase
Sucrase
Maltase
Lactase
Dipeptidase
Tripeptidase
Lipase
What is the function of the pancreatic lipase?
Digests triglycerides
What is the function of the sucrase?
Digests sucrose
What is the function of maltase?
Digests maltose
What is the function of lactase?
DIgests lactose
What is the function of dipeptidase?
Digests dipeptides
What is the function of tripeptidase?
Digests tripeptides
What is the function of lipase?
Digests monoglycerides
What is the pancreas?
A gland organ in the digestive and endocrine systems
What is the main characteristic of the pancreas?
It is both an exocrine and endocrine organ
What is meant by the fact that the pancreas is an endocrine organ?
Secretes products directly into the bloodstream
What are the hormones that the endocrine part of the pancreas produces?
Insulin, glucoagon and somatostatin
What is meant by the fact that the pancreas is an exocrine organ?
It secretes substances into a ductal system
What is the function of the exocrine part of the pancreas?
Secretes pancreatic juice containing digestive enzymes that pass to the small intestine
What is the function of the enzymes secreted by the exocrine part of the pancreas?
Help in further breakdown of the carbohydrates, fat & proteins
What % of the pancreas do the endocrine cells make?
1%, they are observed as Islets of Langerhans
What are the different kinds of endocrine cells?
Alpha
Beta
Delta
F
What do alpha cells secrete?
Glucagon
What do beta cells secrete?
Insulin
What do delta cells secrete?
Human Growth Hormone
Inhibiting Hormone
What is inhibiting hormone?
Inhibit secretion of both glucagon and insulin and slows rate of nutrient absorption
What do F cells secrete?
Pancreatic polypeptide
What is the function of pancreatic polypetide?
Inhibit secretion of digestive enzymes
Inhibit contraction of the gallbladder
What is the pancreatic secretion?
An alkaline liquid secreted by the pancreas, which contains a variety of enzymes
What is the composition of pancreatic secretion?
The first component and second component
What is the first component of the composition of pancreatic secretion?
A solution of bicarbonate, Na+, K+ and water emitted by epithelial cells that line the pancreatic ducts
What is the purpose of the alkaline solution of the pancreatic secretion?
To help neutralize stomach acid so that the digestive enzymes can work more effectively
What are the enzymes in the enzymatic component of the pancreatic secretion?
Trypsinogen
Chymotrypsinogen
Carboxypeptidase
Pancreatic amylase
Pancreatic lipases
Deoxyribonucleases
Ribonucleases
What is the second component of pancreatic secretion?
The enzymatic component which includes multiple enzymes
What is the reaction between water and carbon dioxide catalysed by in the bicarbonate ion production?
Carbonic anhydrase, it forms carbonic acid
What happens to carbonic acid in the bicarbonate ion production process?
Carbonic acid dissociates into hydrogen ions and bicarnate ions
What is the result of the movement of HCO3- and Na+ into the lumen?
This causes an osmotic gradient, which causes the water to move from the blood
The complete digestion of food requires what?
Both pancreatic and brush border enzymes
What are most pancreatic enzymes produced as?
Zymogens
What is the function of enterokinase?
Converts trypsinogen into trypsin
What happens when trypsin is activated by enterokinase?
Triggers the activation of other pancreatic enzymes
What is the function of the pancreatic trypsin inhibitor?
It attaches to trypsin and inhibits its activity in the pancreas
What is the hormonal regulation of pancreatic secretion?
Secretin
CCK
Vasoactive Intestinal Peptide
When is secretin released in regards to pancreatic secretions?
When the acidic chyme from the stomach enters the duodenum, the acid stimulates the duodenal mucosal cells to release secretin
What is the function of secretin in regards to pancreatic secretion regulation?
Stimulates the centroacinar (ductal) cells of the pancreas to release bicarbonate-rich fluid, which neutralizes the acidic chyme, providing suitable pH for th action of digestive enzymes
What causes the release of CCK in from the pancreas?
Fats and partially digested proteins in the duodenum stimulate the release of CCK
What is the function of CCK in regard to pancreatic secretion regulation?
Stimulate acinar cells of the pancreas to release digestive enzymes
Slows down gastric emptying, ensuring that the duodenum is not overloaded with chyme
Inducing the gallbladder to contract and release bile into the duodenum, aiding in fat digestion
What is the function of VIP in regards to pancreatic secretion regulation?
Inducing watery pancreatic secretions
What is the nervous regulation of the pancreatic secretion?
Vagal stimulation
How is pancreatic secretion regulated by the vagal nerve?
Stimulate the pancreas to secrete its digestive enzymes during the cephalic and gastric phases of digestion
What is the difference between the vagal and the nervous regulation of pancreatic secretion?
Vagal regulation has a DIRECT effect on the pancreatic cells (through acetylcholine)
What are cephalic and gastric phases triggered by?
Sight, smell and presence of food in the stomach
What are the phases of pancreatic secretion?
Same as gastric secretion: cephalic, gastric and intestinal
Explain the cephalic phase of pancreatic regulation?
Conditioned or unconditioned reflex –> vagus nerve –> pancreas (secretion of pancreatic juice)
What % of pancreatic juice is secreted through the gastric phase?
About 20%