Steps of monosaccharide metabolism
1. The monosaccharides circulating in the bloodstream enter cells to undergo cellular respiration.
Glucose requires insulin to enter cells, but fructose and galactose do not.
*What if diabetics only ate fructose and galactose-would their blood sugar always be normal? They wouldn't need insulin, then, it seems...
*Is glucagon/epinephrine/cortisol required for weight loss?
*The only reason why a person loses weight is because the body has to use its own stored energy reserves to maintain proper blood sugar level, since food intake is not sufficient to maintain blood sugar?
*It seems to me that glucagon, epinephrine, or cortisol would be required for weight loss, because isn't glycogenolysis and subsequently, gluconeogenesis the only thing that causes energy reserves to get used?
*Even though an untreated type 1 diabetic has a high blood sugar, they still undergo glycogenolysis and gluconeogenesis?
*I know they lose a lot of weight- is this so that their normal body cells can get energy from ketone bodies, at least?
*I know the brain has a different type of GLUT receptor that doesn't require insulin, so the brain of an untreated type 1 diabetic is able to utilize glucose?
*Since most normal body cells do need insulin to take up glucose, do they instead have to run off of ketone bodies when insulin is not present?
*If this is the case, wouldn't weight loss in untreated type 1 diabetics actually make their blood sugar go even higher but also be necessary, since their other body cells can't function without ketone bodies for fuel?
*Do type 1 diabetics produce glucagon. It does not seem like they would be able to- otherwise, why is a glucagon injection necessary when their blood sugar goes too low?
*If they don't produce glucagon (even though it's produced by panceatic alpha cells, which should not be affected...), then how does their body know to lose weight and undergo gluconeogenesis?
*Is their weight loss only controlled by epinephrine and cortisol...?
*If an untreated type 1 diabetic were to completely fast, their blood sugar would never decrease to normal, would it?
*Is this because even though the brain uses up glucose, their fat/protein stores are always being broken down into more glucose + ketone bodies (to supply most body cells)?
*Do cells always take up glucose against the concentration gradient?
Is there ever a time when cells are too full of sugar and won't take up any more?
I know I've asked a ton of questions, but I have seriously tried to look up and figure this stuff out forever! I can't seem to find the answers anywhere!
Thanks so much!