Carbohydrate Flashcards
How much glycogen can be stored in the body?
Enough for us to last the night. Depletion of glycogen usually occurs just as we wake up
When there is excess glucose, which pathway will be dominant?
pentose phosphate pathway for fat and cholesterol synthesis
How is glucose cyclised?
the reactive aldehyde attacks the OH on the 5th carbon
T/F most human glucose is in the alpha form
True, beta form is more found in cellulose
Which molecule triggers insulin release
glucose 6-P
How is glucagon release triggered?
by low circulating blood glucose
Which enzyme makes glycogen? Which enzyme breaks it down?
glycogen synthase to make
glycogen phosphorylase to break
Why is glycogen an ideal glucose store?
it is inert, can be rapidly converted to glucose, same osmotic effect as a molecule of glucose (so liver doesn’t swell)
What is in the centre of glycogen
glycogenin
How does Pompes disease occur?
lack of alpha 1,4-glucosidase, so there is a build up of glycogen
T/F Glucagon and stress signal have a common pathway
True, they both use cAMP pathway to turn off storage and turn on usage of glycogen
What makes cellulose so tough
hydrogen bonds
What features show that humans are true omnivores
teeth - incisors designed to cut, molars designed to crush and grind
Gut - intermediate length
How is white rice different from brown rice?
white rice is the isolated endosperm of grain, whereas brown rice still contains bran and germ, making it harder to digest (low GI)
T/F Thiamin and fiber are low in whole grain bread
False, they are low in white bread
