Pancreas Pancreas w Anatomy w Located retroperitoneal posterior

Pancreas

Pancreas w Anatomy w Located retroperitoneal, posterior to stomach w Midportion from the upper right to the left quadrant w Parts w Head w Body w Tail

Pancreas w Complex organ w Two types of function w Exocrine function w Endocrine function

Function of Pancreas w Exocrine function w Compound acinar gland – connects to small ducts – connects to larger ducts – joins the pancreatic duct – joins the common bile duct and enters the duodenum (small bowel)

Function of Pancreas w What are the secretions and what do they do? w Hco 3 w Enzymes to digest protein w w Trypsin Chymotrypsin Carboxypeptidases Nuclease w Enzyme to digest Carbohydrate w Pancreatic amylase w Enzymes to digest Lipids w Pancreatic lipase

Function of Pancreas w Control of function Form Hormonal Neural Initiating factor Result Secretin Acidic chyme Large amounts of HCO 3 to neutralize acid Cholecystokinin Fatty acids and amino acids Digest fatty acid and amino acids Parasympathetic stimulus food Secretion of enzymes into the gut

Function of Pancreas w Endocrine function w Specialised cells (tissue) – secretes hormones directly into blood stream

Digestion w Digestion – breaking down of food to molecules w Mechanical – larger to smaller w Chemical – breaking of covalent bonds

Digestion, Absorption and Transport

Digestion w Digestion – breaking down of food to molecules w Carbohydrates – monosaccharides w Protein – aminoacids w Fats – fatty acids and glycerol

Absorption w Absorption – begins in the stomach w Mainly alcohol, asprin but NOT the three main food products

Transport w Transport – move the molecules across the intestinal wall w Facillitated diffusion- no need energy w e. g glcose from cell to blood w Cotransport – requires energy w e. g glucose from intestine to cell w Active transport – requires energy w e. g amino acid from blood to organs

Carbohydrate, Lipid Protein , Water and Mineral

Carbohydrate w Cellulose w (plant cell- fiber not carbohydrate) w Starches Complex carbohydrate w (plant energy storage molecule) w Glycogen w ( muscle energy storage molecule) w Sucrose w Fructose w Lactose Disacharide

Carbohydrate Digestion Salivary amylase Complex carbohydrate Polysaccharides Pancreatic amylase Disacharides Polysaccharides Disacharidaseintestine Disacharide Monosaccharides

Carbohydrate Digestion -Sucrose Disaccharidase -Glucose + Glucose -Fructose -Glucose + Maltose -Lactose -Glucose + Galactose Disaccharide Monosacharide

Carbohydrate Intestine w Absorption and Transport Intestine cell Cotransport Blood/capillary Facillitated diffusion w Glucose is the end product in blood is a source of energy is stored and use by the cells and increased/decreased by the presence of insulin

Lipids w Triglycerides – three fatty acids and glycerol w Phospholipids – required for transport and solubility of fat w Steroids w Cholesterol, corticosteroid, esters

Digestion Lipids Emulsification by bile salts Lipid Transforms large lipid into smaller droplets Pancreatic amylase Transforms large lipid into smaller droplets Fatty acid and monoacylglyc erides

Lipids w Absorption and Transport Intestine Simple diffusion Within Intestine cell they are packed into Exocytosis chylomicron Carried in lacteals as chyle into liver and stored as cholesterol, LDL, HDL, Triglyceride and cholesterol is the end product in blood is a source of energy is stored and use by the cells

Proteins w Plant protein w Animal protein

Digestion Proteins Pepsin Protein Polypeptides Trypsin, chymotrypsin, carboxypeptidase Polypeptides Peptidases Peptides Amino acids

Protein w Absorption and Transport Intestine Cotransport Within Intestine cell they brokendown to. Active amino acid transport Carried in blood to liver and throughout the body Amino acid is the end product in blood is a source of building block and the rest is metabolised to release energy and indirectly converted to small amounts of glycogen and the rest as fat which is stored and use by the cells. Transport is stimulated by growth hormone and insulin

Water and Mineral w 9 liters enters the digestive tract w 2 l – food w 1 l – salivary gland w 2 L – Gastric secretion w 1. 2 L – Pancreatic secretion w 0. 7 L – Bile w 2 L – Small intestine 97% absorbed in small intestine 6 -7% in large intestine 1% excreted in faeces

Water and Mineral w Absorption and Transport Intestine Within Intestine Osmosis Blood Osmosis Na , K, Ca, Mg, PO 4, Cl- Blood Active transport Passive transport in duodenum /Active transport in ileum