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Monosaccharides as ____________________________
Vocabulary:
_____________ - gain of oxygen, loss of hydrogen (or loss
of electrons)
______________ - loss of oxygen, gain of hydrogen (or
gain of electrons)
_______________ - Substance which causes the oxidation
of another substance. During a redox reaction the
oxidizing agent itself is reduced.
________________ - Substance which causes the
reduction of another substance. During a redox reaction
the reducing agent itself is oxidized.
Reducing sugar - a sugar (saccharide) that __________
_____________________________________such as
 _____________ reagent (silver mirror test)
 ____________ or ________ reagents (uses Cu2+ ion)
(citrate)
(tartrate)
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With these tests the reagent gets reduced while the _____
____________________________________.
oxidation of aldehydes:
In solution, monosaccharides -predominantly in cyclic
forms.
The cyclic hemiacetals or hemiketals cannot react directly
with the oxidizing agents.
Recall equilibrium for glucose (an aldose):
The ____________________ form. The trace amount of
linear form will react.
The equilibrium shifts by Le Chatelier’s Principle.
Eventually, all will react.
All monosaccharide aldoses are aldehydes and can react
with the oxidizing agents.
They all are _______________________
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Ketones normally do not react with mild oxidizing agents.
However, the ketoses are __________________. These
are in equilibrium with an aldehyde form.
The aldehyde form is a reducing sugar.
Therefore, all monosaccharide ketoses are also reducing
sugars.
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__________________ - (have 2 linked monosaccharides)
We will examine:
 ____________ - _____________, main carbohydrate in
mammalian milk (people who are lactose intolerant lack
the enzyme lactase and cannot digest milk)
 ______________ - ______________
Recall from organic chemistry:
hemiacetal
+
hemiketal
+
alcohol
alcohol
⇄ acetal
⇄
ketal
+
water
+
water
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Lactose
-D- galactose + -D-glucose  lactose +
water
An _________________________ joins the monomers.
The link here is __________________
Question? Is lactose a reducing sugar?
Answer_________________________________________
_______________________________________________
_______________________________________________
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Sucrose
-D-glucose + -D-fructose
 sucrose +
water
Note: Fructose’s normal Haworth projection is flipped
here to put reactive groups close.
Link is _______________________
Question? Is sucrose a reducing sugar?
Answer. No, because the glycosidic bond joins the
anomeric carbon atoms from both monomers. Neither
monomer is any longer in equilibrium with the reactive
linear form (rings are locked in place and cannot open up).
No reaction with Tollen’s, Benedict’s or Fehling’s
reagents. Sucrose is a ___________________________.
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____________________s - (polymers of monosaccharides)
Polysaccharides are also called _______________
_____________ - homopolymer (identical monomer units)
_____________ - heteropolymer (2 or more types of
monomer units)
Polysaccharides can be either branched or linear
polymers.
We will look at:
Starch
Glycogen
Cellulose
1. ______ – in __________ granules  ______________
Starch is a _____________ of 2 polysaccharides
________ - monomer is _______________
_________________________
_____________ 2o structure
_____________ linkage
__________ - monomer is ______________
__________________________
branching prevents helix formation
main chain is _____________
branch points are _________ linkage
branches  _______ units apart; length about ______ units
_______- digestive enzyme (saliva) ______________ links
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2. ____________ - found in ______, primarily in the ____
in mammals, ___________, regulates blood glucose levels
10% of the liver is glycogen
2% in muscle
Structure is nearly ______________________
Differences from amylopectin:



_________________
more ________________ from main chain (every
_______________ units)
branches are ___________
3. _______________ - most abundant polysaccharide
main component of _____________ (structural function);
strong to withstand changes in turgor pressure.
monomer is ____________________
_______________________
has ________________ linkage
____________ fibers, can ________ form layers
very strong
Hydrolyzed by the ________________. Humans do not
have this, so don't eat grass!
Cows, termites, etc. have cellulase by the microrganisms in
their digestive systems.