8.2 Endocrine Organs and Hormones Flashcards
How much glucose does the body requires?
Body cells require a regular supply of glucose for cellular respiration; brain cells, in particular, could die quickly when deprived of glucose.
What should happen to blood glucose levels?
Maintained above a specific value.
What happens when the blood glucose level is high?
It has several harmful effects, such as damaging blood vessels.
What helps in keeping the blood glucose level within a specific range?
The endocrine portion of the pancreas with the help of the liver play a significant role in this regulation.
What is the pancreas made up of? Describe what happens there.
Most of the pancreas is composed of exocrine cells that secrete pancreatic juice into special ducts that eventually reach the small intestine.
Define the islets of Langerhans.
The endocrine cells of the pancreas are scattered throughout the tissue of this organ, in groups called the islets of Langerhans.
What does the islets of Langerhans produce?
2 hormones: insulin and glucagon.
What do insulin and glucagon do?
Regulate blood glucose levels.
What’s the function of insulin?
It causes a decrease in blood glucose levels.
What’s the function of glucagon?
It causes an increase in blood glucose levels.
What can you conclude about glucagon and insulin?
They have opposite effects on blood glucose levels.
What happens to the human body after a meal rich in carbohydrates?
The amount of glucose in the blood rises above normal levels.
What does the islets of Langerhans do after the blood glucose level had risen?
The islets of Langerhans cells in the pancreas detect the increase in blood glucose and secrete insulin into the blood.
What happens after the insulin had been released?
The liver and the muscle cells, 2 major target organs of insulin, respond by absorbing glucose from the blood, which will be used in cellular respiration or stored in the form of glycogen.
What happens once the glucose had been taken care of?
It lowers blood glucose levels and helps bring them back to normal values.
What happens to the islets of Langerhans when blood glucose levels drop below normal levels whilst fasting?
The islets cells secrete glucagon into the blood.
What does the glucagon do?
It stimulates the liver to break down glycogen into glucose for release into the blood, which raises blood glucose levels.
Define diabetes.
Diabetes mellitus, or simply diabetes, is a disease that occurs when the body fails to regulate blood glucose levels.
How many types of diabetes mellitus?
2 main types of diabetes mellitus: type 1 and type 2
When does Type 1 diabetes usually occur?
Typically appears early in life, during childhood or adolescence.
Describe Type 1 diabetes.
It’s an autoimmune disease that results when the beta cells of the islets of Langerhans are attacked and destroyed by the bidi’s immune system.
What are beta cells?
They are responsible for the production of insulin.
What do people with type 1 diabetes lack?
They lack sufficient insulin for glucose regulation.
What happens to people with type 1 diabetes after a mean rich in carbohydrates?
Since people with type 1 diabetes produce little or no insulin, blood glucose levels cannot be reduced to normal values, and a condition knows as hyperglycemia will occur.
Define hyperglycemia.
An excess of glucose in the bloodstream.
What are symptoms of hyperglycemia?
Blurred vision, increased thirst, and frequent urination.
What can hyperglycemia cause glucose to do?
Be excreted in urine.
Does urine usually contain glucose? Explain why.
Urine normally does not contain significant amounts of glucose because this nutrient is fully reabsorbed into the blood from the filtrate in the kidneys.
Will all the glucose be reabsorbed into the blood?
Only a certain amount of glucose can be reabsorbed by the kidneys; thus, high concentrations of glucose in the blood will result in some glucose being excreted in the urine.
What do individuals with diabetes have a hard time doing?
They have difficulty raising their blood glucose levels to normal values during periods of fasting or inadequate food intake.
What does insulin and glucagon normally do?
Insulin stimulates the liver to store glucose in the form of glycogen, forming reserves in the body for periods of limited glucose intake, and glucagon triggers the breakdown of these reserves into glucose to be released into the blood, bringing glucose levels back to normal.
What happens, as a result, in people with type 1 diabetes?
Since little or no insulin is secreted in individuals with type 1 diabetes, glycogen is not formed.
What are people with type 1 diabetes at the hight risk of?
Diabetic patients are at a high risk of developing a condition known as hypoglycemia.
Define hypoglycemia.
A deficiency of glucose in the bloodstream.
What are symptoms of hypoglycemia?
Confusion, shakiness, sweating, hunger, and weakness.
What can extreme fluctuations in blood glucose levels lead to?
Organ damage, coma, and even death.
How can individuals with type 1 diabetes be protected from extreme fluctuations in blood glucose levels?
By taking insulin injections, eating regularly, and avoiding meals rich in carbohydrates.