chapter 20 - carbohydrates Flashcards
what is a monosaccharide?
carbohydrate with 3-7 carbon atoms
what is an aldose?
monosaccharide with aldehyde functional group
what is a ketose?
monosaccharide with ketone functional group
what are the two common aldohexose?
glucose
galactose
what is the common ketohexose?
fructose
what is another name for glucose?
“blood sugar”
what was glucose originally mistaken for?
hydrate of carbon
what types of polysaccharides does glucose help make up?
starch
cellulose
glycogen
Glucose is a ____________ of many common polysaccharides
monomer
how does glucose move around the body? is it slow or quick energy?
blood stream
quick energy
what is normal range of blood glucose levels?
70 - 110 mg/dL
what is excess glucose converted into?
glycogen or fat
where is galactose commonly found?
cellular membranes of brain/nervous system
what two subunits form lactose?
glucose + galactose
what is galactosemia? what can it cause? what is the treament?
lack enzyme to metabolize galactose causing galactose build up
cataracts, cirrhosis, and mental retardation
avoid lactose-containing milk products
what is the main characteristic of fructose?
it is the sweetest carbohydrate
what subunits form sucrose?
glucose + fructose
what is another name for sucrose?
table sugar
where is fructose commonly found?
honey and some fruits
what is this monosaccharide in general terms?
aldohexose
what is this monosaccharide in general terms?
aldopentose
what is this monosaccharide in general terms?
ketohexose
what is this monosaccharide in general terms?
aldotriose
are monosaccharides chiral or achiral?
chiral
enantiomers vs diastereomer
do diastereomers have 1 chiral carbon or more than 1?
must have more than 1
make D-glucose into its alpha/beta hemiacetal Haworth projection version
D-glucose exists between both cyclic versions and its open-chain structure, which is it most likely to exist as?
what is the process of molecule existing as both its hemiacetal versions and its open-chain version?
mutarotation
what does a glycosidic formation require?
hemiacetal + alcohol + catalyst -> acetal + water
what is the product? what is the name of the type of glycosidic bond?
alpha glycosidic bond
what is this type of reaction? products?
polysaccharide hydrolysis
what type of reaction? what is the product?
Phosphorylation
what is a reducing sugar?
a carbohydrate that reacts in basic solution with a mild oxidizing agent (requires an aldehyde/ hemiacetal functional group)
can nonreducing sugars be oxidized?
no
are ketoses reducing sugars?
yes, they tautomerize to aldoses
what type of reaction? what is the product?
oxidation reaction
this is a maltose structure. is it alpha or beta maltose?
alpha-maltose
is maltose a reducing sugar?
yes
is lactose a reducing structure?
yes
is sucrose a reducing sugar? why?
no, it does not have a hemiacetal functional group
what type of glycosidic bond?
what type of glycosidic bond does alpha maltose have?
alpha-1,4
what type of glycosidic bond?
beta-1,4
what is a polysaccharide?
polymer composed of many monosaccharides
which organism is the only able to digest cellulose? how?
termites
with the help of bacteria in their gut
is cellulose a reducing sugar
no, because only one end of very many subunits will react with Fehling’s test. Not enough to produce a visible positive result
what are amylose and amylopectin examples of?
starches
what percent is amylose and amylopectin found in?
amylose - 20% of starch
amylopectin - 80% of starch
is amylose soluble in water?
yes, somewhat
what is difference between amylose and amylopectin?
amylose is made up of many glucose subunits and alpha-1,4 glycosidic bonds
amylopectin is made up of many glucose subunits and alpha-1,4 glycosidic bonds, but contains alpha-1,6 branches every 25 subunits
is amylopectin soluble in water?
no
what is the most abundant polysaccharide? second-most?
cellulose
chitin
what is chitin?
a carbohydrate derivative made up of poly glucosamine
where is chitin commonly found?
shell of lobster, beetle, spider
what are glycoproteins?
a protein that contains a short carbohydrate chain (oligosaccharide chain)
where can glycoproteins be found?
attached to proteins
how is blood type determined?
based on what monosaccharides are attached to the membrane protein of red blood cells
type A has what monosaccharide is attached?
type B blood has what monosaccharide attached?
draw Haworth projection of beta-D-galactose
what is the relationship between alpha and beta monosaccharides?
they are anomers
what is the process of a cyclic alpha going to open chain form, then to beta or back again?
mutarotation
draw beta-L-galactose
