The Pancreas

Question 1

Describe the appearance and position of the pancreas

Answer 1

• accessory digestive organ
• pink-yellow gland
• situated just below the stomach
• head is surrounded by loop of duodenum

Question 2

What is in the pancreatic juice produced by the exocrine glands?

Answer 2

• water, salts, sodium bicarbonate and enzymes
• the sodium bicarbonate gives the pancreatic juice an alkaline pH necessary for the pancreatic enzymes to act on the chyme in the duodenum

Question 3

Describe the function of the pancreas in relation to its exocrine and endocrine function

Answer 3

• An organ which is both an Endocrine gland and an Exocrine gland
• Cells with an EXOCRINE function (acinar cells) are found in clusters around the pancreatic duct - secrete digestive enzymes into the pancreatic duct, they are then carried in fluid to the small intestine
• trypsin and chymotrypsin - digest proteins
• pancreatic amylase - digest carbohydrates
• pancreatic lipase - digest fats

• cells with an ENDOCRINE function (islet of langerhans) are made up of alpha and beta cells

     - found in clusters around blood capillaries 
     - secrete hormones directly into the blood 
     - a cells - manufacture and secrete glucagon 
     - B cells - manufacture and secrete insulin

Question 4

Describe what happens if glucose levels rise

Answer 4

• Detected by Beta Cells in the Islet of Langherans (IoL)
• Beta Cells secrete Insulin into the blood
• Insulin binds to receptors on hepatocytes
• Muscle Cells take up Glucose and convert it to Glycogen or use it in respiration.
• Hepatocytes take up Glucose and convert it to Glycogen (GLYCOGENESIS)
• Blood Glucose levels fall back normal levels

Question 5

Describe what happens if blood glucose levels fall

Answer 5

• Detected by Alpha Cells in the Islet of Langherans (IoL)
• Alpha Cells secrete Glucagon into the blood
• Glucagon binds to receptors on Hepatocytes
• Hepatocytes releases Glucose by Glycogenolysis.
• Glycogen ▶️ Glucose (GLUCONEOGENESIS)
• Making new Glucose from Amino Acids
• Glucose is released into the blood
• Blood Glucose levels rise back normal levels