Sugar transport, metabolism, and glycolysis Flashcards
(96 cards)
which starch is branched and soluble?
amylopectin
which starch is not branched and insoluble?
amylose
what general enzyme breaks down starch?
alpha-amylase
how does alpha-amylase act as an endoglycosidase?
it cleave polysaccharide chains between residues that are not the terminal residue, so it breaks internal bonds
which bond specifically dose alpha-amylase break?
1-4-alpha glycosidic bonds
what kind of carbohydrates does alpha-amylase mainly produce?
di- and trisaccharides
what two places does alpha-amylase reside in the body?
made by pancreas, also appears in saliva
what enzyme complex breaks down di- and trisaccharides?
sucrase-isomaltase complex
how many enzymatic activities does the sucrase-isomaltase complex have and what are they?
3 - 1-4-alpha, 1-6-alpha, and alpha-1-beta-2 glycosidic bonds
what is the end product made by the sucrase isomaltase complex?
monosaccharides, mostly fructose and glucose
where in the body does the sucrase-isomaltase complex mostly reside?
in the intestinal brush-border membrane
describe an alpha sugar
a sugar that has the -OH group and the -CH2OH group on opposite sides of the ring
describe a beta sugar
a sugar that has both the -OH group and the -CH2OH group on the same side of the ring
fructose + glucose = ?
sucrose
what breaks down sucrose?
sucrase
matlose = ___ + ____
glucose + glucose
what breaks down maltose
maltase
describe a non-reducing sugar
has both anomeric carbons bonded to the same O, has a formation of C-O-C-O-C-O-C
describe a reducing sugar
one anomeric carbon is bonded to the O joining the 2 sugars, but not the other, forms C-O-C-O-C-C
what process happens to form an inverted sugar
a hydrolysis reaction or degradation by invertase where the optical rotation changes from + to -
what kind of bond does lactase break?
the beta-glycosidic bonds in lactose
what are the components that lactose are broken down into by lactase?
glucose and galactose
what kind of bond does trehalase break?
an alpha-1-alpha-1 glycosidic bond between two glucose moecules
what components is trehalose broken down into by trehalase?
2 glucose molecules