CARBOHYDRATES Flashcards
An entire complement of sugars of an organism
GLYCOME
Study of glycomes, including genetic, ohysiological, pathological, and other aspects.
GLYCOMICS
Major constituents of animal food and animal tissues. Characterized by the type and number of monosaccharide residues
CARBOHYDRATES
Most important carbohydrate in mammalian, nearly all carbohydrate in food is converted to this for metabolism
GLUCOSE
Have large number of stereoisomers because they contain several asymmetric carbon atoms
SUGAR (GLUCOSE)
Physiologically important monosaccharides:
Glucose (“ the blood sugar”)
Ribose - nucleotides and nucleic acids
Important disaccharides:
Maltose (glucosyl-glucose) - intermediate in digestion of starch
Sucrose (glucosyl-fructose) - dietary constituent containing fructose
Lactose (galactosyl-glucose) - milk
Storage polymers of glucose in plants. Major metabolic fuel in the diet.
STARCH
Storage polymers of glucose in animals
GLYCOGEN
A precursor for synthesis of all the other carbohydrates in the body including glycogen (storage), ribose and deoxyribose (nucleic acids), galactose (synthesis lactose in milk)
GLUCOSE
Disease associated w/ carbohydrate metabolism
Diabetes mellitus, galactosemia, glycogen storage diseases, and lactose intolerance
Carbohydrates classified as:
Monosaccharides
Disaccharides
Oligosaccharides
Polysaccharides
These sugars cannot be hydrolyzed into simpler carbohydrates, can be classified depending on whether they have an aldehyde or ketone group.
MONOSACCHARIDES
Monosaccharides classified as:
Trioses,
Tetroses
Pentoses
Hexoses or heptoses
Aldoses or Ketoses
Trioses :
Aldoses: Glycerose (Glyceraldehyde)
Ketoses: Dihydroxyacetone
Tetroses:
Aldoses: Erythrose
Ketoses: Erythrulose
Pentoses:
Aldoses: Ribose
Ketoses: Ribulose
Hexoses:
Aldoses: Glucose, galactose, mannose
Ketoses: Fructose
Heptoses:
Ketoses: Sedoheptulose
Formed by the condensation of 2 monosaccharide units
DISACCHARIDES
(ex. lactose, maltose, isomaltose, sucrose, trehalose)
Condensation products of 3 to 10 monosaccharides. Most are not digested by human enzymes
OLIGOSACCHARIDES
Condensation products of more than 10 monosaccharide units. Sometimes classified as hexosans or pentosans.
POLYSACCHARIDES
Nonstarch polysaccharides that are not digested by human enzymes but a major components of dietary fiber:
Cellulose (glucose polymer) - from plant
Inulin (fructose polymer) - storage carbohydrate in some plants
The structure of glucose can be represented in 3 ways:
- Straight-chain form
- alpha-D-glucose (Haworth projection)
C. alpha-D-glucose (Chair form)
Important types of isomerism found in glucose:
- D-and-L-isomerism
- Optical isomer
- Pyranose and Furanose ring structures
- Alpha-and beta-anomers
- Epimers
- Aldose-ketose isomerism
When the sugar is on the left:
D-isomer
When the sugar is on the right:
L-isomer
When the polarized light rotates to the right:
Dextrorotatory (+)
When the polarized light rotates to the left:
Levorotatory (-)
Glucose is dextrorotatory and glucose solution are sometimes known as
DEXTROSE
Monosaccharides that has a six-membered ring
PYRAN
A ring structure of monosaccharides that have a five-membered ring
FURAN/FURANOSE
Ring structure of an aldose is______, formed by reaction between aldehyde and an alcohol group
Hemiacetal
