1. disaccharides + alcohol aldehyde hemi-acetal unstable + + H2O
condensation

2. disaccharides D-lactose condensation -D-galactose -D-glucoseHO
CH2OH
CH2OH 4 HO OH HO 1 2 HO 1 OH OH 3 OH
-D-galactose
-D-glucose
C1 galactose
+ C4 of glucose
D-glucose
D-galactose
glycoside bond -
1,4

3. can’t be absorbed by intestines hydrolyzed by enzyme lactase
+ H2O
-D-galactose
-D-glucose
-1,4-glycoside
lactose
milk sugar
can’t be absorbed by intestines
hydrolyzed by enzyme lactase
Is this a reducing sugar?
acetal
stable
hemi-acetal
unstable
reducing sugar

4. sucrose condensation -D-glucose -D-fructose -D-glucose - - 1,2-3 4 5 6
condensation
-D-glucose
-D-fructose
CH2OH HO HO O HO OH OH 6 4
-D-glucose OH
CH2OH 3 - -
1,2-
glycoside HO 2 5
sucrose 1
HOH2C -
D-fructose

5. Reducing disaccharides 4 1 1   2 -
1,4-
glycoside
,  -
1,2-
glycoside
lactose
sucrose
lactose =
head -to-tail
sucrose =
head -to-head
one hemi-acetal
no hemi-ketal
reducing sugar
non-reducing sugar
all monosaccharides are reducing

6. Polysaccharides 2 glucose molecules -1,4-glycoside maltose
hemi-acetal
homo-polysaccharide
only glucose
-1,4-linkages
starch
amylose
4,000 glucose

7. Starches amylose helical -1,4-linkages
alternating axial and equatorial
4000 glucose  4
amilopectin 1
glucose 6 
“branching”
-1,6-linkages 1
glycogen
carbohydrate in animals
smaller “chain”
more highly branched

8. Cellulose homo-polysaccharide of glucose -1,4 linkages
equatorial-equatorial linkages
long, straight chains
-1,4 linkages
difficult to hydrolyze
structural saccharides

9. Cellulose H-bonds between adjacent chains form fibers
cotton and flax are cellulose