Lecture 10.13.14 (Exam #3) Flashcards
Carbohydrates
major source of energy in our body
(CH2O)n
made by plants
How are carbohydrates classified?
Complexity
Size
Functional Groups
Complexity of carbohydrates
Mono: 1 sugar
Di: 2 sugars
Oligo: few sugars (15 or less)
Poly: many sugars
Size of carbohydrates
the number of carbons in the sugar
ex. 3-triose; 5-pentose
Functional Group of carbohydrates
most commonly used
ex. aldose & ketose
aldose
sugar with aldehyde (always have -OH group)
usually at one end
ketose
sugar with ketone C=O
usually at C2
D vs. L
How a molecule with more than 1 chiral carbon polarizes light
stereoisomers
D: right
L: left
D-glucose vs L- glucose
D-glucose: OH furthest from C=O is on the right side
L-glucose: OH furthest from C=O is on the left side
During the cyclization of glucose what gets attacked?
-O of C5 attacks C1
alpha corresponds to________
down & axial (C1)
beta corresponds to________
up & equatorial (C1)
anomers
2 molecules that differ in 1 chiral center;refers to alpha and beta
cyclization of glucose refers to
the synthesis of hemiacetal
hemiacetal
C-O-C-O-H
glucose ring type
pyran
pyranose sugar
5C & 1O
During the cyclization of fructose what gets attacked?
-O of C5 attacks C2
fructose ring type
furan
furanose sugar
ketose sugar
4C & 1O
Other types of sugars (2)
sugar alcohol
amino sugar
sugar alcohol
sugar without ketone or aldehyde
glycosidic bond/linkage
bond between sugar & something else
O-glycosidic bond
sugar + something else linked by O atom
N-glycosidic bond
sugar + something else linked by N atom
How can glucose molecules be linked together?
dehydration synthesis (make) hydrolysis synthesis (break)
alpha 1,4 linkage is ______
down
beta 1,4 linkage is ______
up
