(F) Carbohydrates part 1 Flashcards
most abundant organic molecules in nature
carbohydrates
components of carbohydrates
carbon, hydrogen and oxygen
most important carbohydrate in the body
glucose
what is the empiric for many of the simpler carbohydrates
(CnH2O)n
*n=3
other term for carbohydrates
“hydrate of carbon”
how much energy is released from 1 g of carbs
4 kilocal/g
how many percentage of our food intake is carbs
65%
T or F
Carbohydrates serve as intermediates for the biosynthesis of lipids, proteins, and nucleic acids
T
Carbs form a part of the structural framework of ____ and _____
DNA and RNA
Carbohydrates link with _____ serve as a structural component for cell membranes
lipids
T or F
Carbs do not form a structural tissue in plants and in other microorganisms
F (they do)
Carbs needs to collaborate with ____ to participate in biological transport and regulatory functions in cell-cell recognition
proteins
excess sugar is stored as _____ in animals
glycogen
In what form is excess sugar stored in plants?
starch
what is the sugar found in A blood type
N-acetylgalactosamine
what is the sugar found in B blood type
D-galactose
what is the sugar found in AB blood type
both sugars:
N-acetylgalactosamine and D-galactose
what is the sugar found in O blood type
none (absence of both sugars)
T or F
Every carbon contains your hydroxyl group even the one that is double bonded with oxygen
F (all contains hydroxyl EXCEPT for the carbon double bonded to oxygen)
how many sugar does monosaccharides have
1
how many sugar does disaccharides have
2
how many sugar does oligosaccharides have
2-10
how many sugar does polysaccharides have
more than 10
what type of bond connect sugar units
glycosidic linkages
T or F
all major classes of carbs based on the amount of sugar units needs an enzyme to be digested/converted into ATP
F (not all since monosaccharides cannot be digested further)
what determines the functional group of your carbohydrates
position of carbonyl group
two types of functional group based on the carbonyl position
aldose sugar
ketose sugar
other name for aldose sugar
polyhydroxy aldehyde
other name for ketose sugar
polyhydroxy ketone
T or F
Lobry Van Bruyn Transformation is an irreversible reaction
F (reversible)
Why is the Lobry Van Bruyn Transformation possible?
because of hydrogen transfer
Simplest aldose sugar
Glyceraldehydes
Simplest Ketose Sugar
Dehydroxyacetone
What are the two tetrose aldose sugars
Erythrose and Threose
The only tetrose ketose sugar
erthrulose
Enumerate the three pentose aldose sugars
xylose
ribose
arabinose
the only pentose ketose sugar
ribulose
the only hexose ketose sugar
fructose
enumerate the three hexose aldose sugars
glucose
galactose
mannose
In naming carbs, what is the first thing that you have to search for
position of the carbonyl group
after knowing whether the carbohydrate is a ketose or aldose, what is the next step?
count the number of carbon atom it contains
what is the last step of naming carbs?”
add the suffix -ose
what is the additional suffix for ketoses?
“ul”
ex. xyulose
what are molecules that have the same chemical formula but different structures
isomers
where does stereoisomers differ?
3D orientation of atoms
what is the most common type of sugar based on the classification by carbon atoms
hexose
in what form does most biologically important chemicals exist as?
stereoisomers
what is D/L isomerism also called as?
enantiomers or mirror images
what is the orientation of the penultimate carbon’s hydroxyl group in L isomerism?
L for left
what is the orientation of the penultimate carbon’s hydroxyl group in D isomerism?
Right
T or F
Carbon chain is written horizontally with c1
F (vertically)
a carbon attached to four different groups
asymmetric / chiral carbon
carbon in the carbonyl group
anomeric carbon (C1)
the highest numbered chiral carbon or the last chiral carbon
penultimate carbon
how many different groups should be attached to a carbon for it to be called a chiral carbon?
4
these are stereoisomers with more than one chiral carbon which differ in chirality at only one chiral center
epimers
what is the rotation of a dextrorotatory carbohydrate?
rotates to the right or clockwise
what is the rotation of a levorotatory carbohydrate?
rotates to the left or counter clockwise
Most L sugars are
a. dextrorotatory
b. levorotatory
b. levorotatory
Most D sugars are
a. dextrorotatory
b. levorotatory
a. dextrorotatory
specific rotation of D-glucose
+52.7
specific rotation of D-fructose
-92
specific rotation of D-galactose
+80.4
specific rotation of lactose
+55.3
specific rotation of sucrose
+66.5
specific rotation of maltose
+130.4
specific rotation of D-Mannose (beater sugar)
+19.5
specific rotation of L-arabinose
+104.5
specific rotation of D-arabinose
-105
specific rotation of D-xyclose
+18.8
specific rotation of Dextrin
+195
specific rotation of Inverted sugar (caramelized sugar)
+19.8
a specific type of formula that designates the orientation of groups
fischer projection
what is a tetrahedral carbon represented by in fischer projection
two crossed lines
most common monosaccharide
glucose
simplest sugars and building blocks of all classes of carbohydrates, thus cannot be hydrolyzed further
monosaccharides
T or F
most monosaccharides are aldoses
T
most important sugar, essential energy source
D-glucose
Sugar abundant in semen, it is used by sperms for energy
D-Fructose
monosaccharide that needs to be converted into glucose as it is toxic
D-Galactose
Disease that causes mental retardation, cataracts, and even death, hence it is included in newborn screening
Galactosemia
a monosaccharide that has a structural function rather than used for energy
D-ribose
most important carbohydrate present in urine in diabetes mellitus
D-Glucose
monosaccharide that can be changed to glucose in the liver
D-fructose
monosaccharide that is synthesized in the mammary gland to become lactose for milk
D-galactose
monosaccharide that is a component of glycolipids and glycoprotein
D-Galactose
monosaccharide that is a structural component of nucleic acids, coenzymes, and flavoenzymes
D-ribose
monosaccharide that serves as an intermediate in the pentose phosphate pathway
D-ribose
formed as a self-reaction when the carbonyl atom reacts with the penultimate carbon to form either a hemiacetal or hemiketal linkage
Ring configuration
term for a six-membered ring
pyranose
term for a five-membered ring
furanose
type of linkage for aldoses
hemiacetal
type of linkage for ketoses
hemiketal
what is added between the carbonyl atom and the penultimate carbon to create a Fischer ring
o-linkage
what form is it when the OH in c1 projects to the right
alpha form
what form is it when the OH in c1 projects to the left
beta form