Lecture 37: Blood Glucose Concentration

Question 1

The pancreas is an _____ and _____ gland.

Answer 1

• Endocrine

- Exocrine

Question 2

In the pancreas, the ____ cells are important for insulin, and the ____ cells are important for glucagon.

Answer 2

• Beta

- Alpha

Question 3

As blood glucose level increases, beta cells secrete _____ into the bloodstream so that ____ _____ and the ____ take up glucose. The _____ is responsible for storing glucose as glycogen.

Answer 3

• Insulin
• Body Cells
• Insulin
• Liver

Question 4

Main role of insulin is to regulate ____ ____.

Answer 4

• Fuel storage

Question 5

Beta cells are both the ____ and _____ of the blood glucose homeostatic system.

Answer 5

• Sensor

- Integrator

Question 6

Target cells of insulin include:

Answer 6

• Muscle & Adipose (fat) Cells

- Liver cells

Question 7

Too much glucose in the fat cells = storage of _______.

Answer 7

• Triglycerides (fat)

Question 8

Once blood glucose concentration falls, the beta cells sense this and…

Answer 8

• Insulin is no longer secreted

Question 9

Glucagon regulates ____ ____.

Answer 9

• Fuel release

Question 10

Pancreatic islet ____ cells secrete _______ when the blood glucose concentration is low. The target cells are the ______ cells which catalyses the breakdown of _____, ______ and ketone synthesis.

Answer 10

• Alpha
• Glucagon
• Liver
• Glycogen
• Glucose

Question 11

What is the difference between glycogen and glucagon?

Answer 11

• Glycogen = stored form of glucose

- Glucagon = hormone

Question 12

Hormones that also increase BGC (blood glucose concentration):

Answer 12

• Growth hormone
• Adrenaline
• Cortisol

Question 13

What mechanism does insulin use (simple)?

Answer 13

• Insulin binds to it’s receptor
• It opens up a glucose channel
• Glucose enters cell through glucose channel

Question 14

What mechanism does insulin use (complicated)?

Answer 14

• Insulin binds to it’s receptor, and becomes phosphorylated
• Stimulates another protein to activate PI-3 kinase
• This binds to a storage vesicle of glucose transporters
• This transporter moves to the membrane
• Channel opens, glucose enters
• If the cell is inactive, glycogen is stored in cell
• If the cell is active, they can use glucose as an energy source
• This can only happen if there are working insulin receptors

Question 15

What causes insulin resistance?

Answer 15

• Lipid accumulation
• No glucose channels in the membrane
• Insulin still binds to receptors but can’t go into the cell

Question 16

Long term insulin resistance leads to…

Answer 16

• Impaired beta cell function

- Beta cell compensation occurs and beta cells get bigger so they can pump out more insulin

Question 17

Type I Diabetes Mellitus:

Answer 17

• Insulin producing beta-cells have been destroyed and insulin levels are low
• Glucose in urine
• High blood glucose
• Insulin injections

Question 18

Type II Diabetes Mellitus:

Answer 18

• Beta cells become overworked, don’t produce as much insulin anymore
• Cells are resistant to insulin’s signal to store fuel
• Treatment includes insulin injections, drugs promoting insulin release such as incretins