Glucose metabolism

Question 1

What are the 3 monosaccharides (C6H12O6)?

Answer 1

• Glucose
• Galactose
• Fructose

Question 2

What are the makeup of the 3 main disaccharides?

Answer 2

• Lactose (glucose + galactose)

- Sucrose (glucose + fructose)

Question 3

What are examples of complex carbs (polysaccharides)?

Answer 3

• Starch
• Glycogen
• Cellulose (“fiber”)

Question 4

What polysaccharide cannot be broken down by animals?

Answer 4

Cellulose (fiber)

- Improves bowel function -> adds bulk to stol

Question 5

What does ribose and NADPH come from?

Answer 5

HMP shunt (requires glucose)

Question 6

What is glucose intake into muscle and the heart dependant on?

Answer 6

Insulin (GLUT4)

Question 7

What important organelle do RBCs lack? and what do they use glucose for?

Answer 7

Mitochondria

• Use glucose for anaerobic metabolism (make ATP)
• Generate lactate
• Also use glucose for HMP shunt

Question 8

What glucose transporters are present in the GI tract?

Answer 8

• SGLT1 (on luminal side, 2Na+ and Glucose)

- GLUT2 (glucose, bidirectional, on basolateral side)

Question 9

What causes a high concentration of Na+ outside the GI cell?

Answer 9

ATP/Na+ pump

- Pumps Na+ out of cell into lumen, creating a conc gradient which then drives glucose uptake

Question 10

Where are GLUT1 transporters found?

Answer 10

• Brain
• RBCs
  Glucose independent

Question 11

Where can bidirectional GLUT-2 transporters be found?

Answer 11

• Liver
• Kidney
• Intestine (into portal vein)
• Pancreas