Lecture 23 Flashcards
(20 cards)
List the 3 major fuel sources used by the body
1) Glucose
2) Fatty acids
3) Amino acids
What is Glucose?
The principal circulating sugar in the blood and the major energy source of the body
What does Glucose metabolism maintain?
Blood glucose levels at 4-6 mM
What is the energy storing molecule?
Glycogen
What is the Absorptive state?
Anabolic: High insulin
What is the energy source of in the Absorptive state?
Glucose
What is the Post absorptive state?
Catabolic: Low insulin
What is the energy source of in the Post absorptive state?
Fatty acids and ketones (Not in the brain)
What is the most abundant amount of cells in the Islets?
60–80% of cells are B cells
What is the Homodimer?
Two identical units, each with an α-subunit and β-subunit
What do the β-subunits do?
Autophosphorylate tyrosine and then phosphorylate insulin receptor substrates
What is a key characteristic of Insulin?
It is the only regulator that decreases blood glucose levels
What is important for long-term regulation of bodyweight?
1) Plasma leptin
2) Plasma ghrelin
Where is Leptin secreted by?
Fat (adipose) cells
When is leptin secreted?
When Energy intake > Energy expenditure
What does leptin secretion depend on?
Fat deposition (Amount of fat in the fat (adipose) tissues)
Where is Ghrelin secreted by?
X/A like cells in the oxyntic glands of stomach
What is the function of Ghrelin?
Suppresses fat utilisation in adipose tissue
What does Ghrelin stimulate?
- Hunger
- Food intake
- Gastric emptying
What is the energy store from fatty acids?
Triglyceride (fat)
