L1.6 CARBS Flashcards
List features shared by all carbohydrates.
- polymerize when a condensation reaction occurs between two hydroxyl groups, resulting in a GLYCOSIDIC LINKAGE
- can be covalently linked into chains to form complex carbohydrates
identify an example of structural isomers
Butane and isobutane (C4H10) are structural isomers
Describe the type of monomer, type of linkage, branching (if any), and major functions of starch, glycogen, and cellulose
Starch and glycogen are storage polysaccharides in plant and animal cells, respectively, that are composed of α-glucose monomers joined by α-glycosidic linkages. Cellulose is a structural polysaccharide in plants, which is composed entirely of β-glucose monomers joined together by β-1,4-glycosidic linkages.
• Explain the major functions that carbohydrates perform in cells
- provide structural support
- function in cellular identity
- store and provide energy for cells
- provide a substrate for synthesizing more complex molecules
α-glycosidic linkage
1,4 alpha glycosidic bonds are formed when the OH on the carbon-1 is below the glucose ring
β-glycosidic linkage
1,4 beta glycosidic bonds are formed when the OH is above the plane
aldose
monosaccharide that contains an aldehyde group (-CHO)
amino sugar
a sugar molecule in which a hydroxyl group has been replaced with an amine group.
carbohydrate
are sugars, which provide chemical energy & function as molecular building blocks
Disaccharide
2 monosaccharides held together by glycosidic linkages
ex: Maltose, Sucrose, Lactose
glucose
- a simple sugar that naturally occurs and is found in fruits and other parts of plants in its free state
- C6H12O6; aka dextrose; is a monosaccharide
- exists in an open-chain (acyclic) and a ring (cyclic) form
glycogen
a multibranched polysaccharide of glucose that serves as a form of energy storage in animals, fungi, and bacteria. The polysaccharide structure represents the main storage form of glucose in the body
(C6H10O5)n
glycoprotein
A molecule that consists of carbohydrate plus a protein; proteins that contain oligosaccharide chains (carbs) covalently attached to amino acid side-chains (protein) .
Glycosidic linkage
Monosaccharides polymerize when a condensation reaction occurs between two hydroxyl groups, Glycosidic linkages can form between any two hydroxyl groups
hexose
a 6-carbon sugar
ex: fructose, a-glucose, a-mannose
ketose
a monosaccharide that contains a ketone (C=O)
monosaccharide
the monomeric unit of carbohydrates
ex: sucrose, maltose, Glucose, Fructose, Galactose
N-acetyl group
an acetyl group that contains a methyl group (CH3) single-bonded to a carbonyl (C=O)
Oligosaccharide
are small polymers of 3-20 monosaccharides
ex: raffinose, maltotriose, Stachyose
pentose
a 5-carbon sugar
ex: ribose and deoxyribose
Polysaccharide
are large polymers of carbohydrates (100-1000)
ex: Starch (Amylose), Glycogen, Cellulose, Chitin
starch
a polysaccharide comprising glucose monomers joined in α 1,4 linkages; occurring in the form of minute granules in the seeds, tubers, and other parts of plants,
structural isomer
are molecules made up of the same kinds and numbers of atoms, but that differ in how their atoms are joined together
The spatial arrangement of hydroxyl groups distinguishes one molecule from another
sugar
the generic term for any disaccharides and monosaccharides. Sugars are an essential structural component of living cells and a source of energy in many organisms. Sugars are classified based on the number of monomeric units present.
- Glucose –> exists as a simple sugar
- Fructose (a.k.a. fruit sugar) –> exists as a simple sugar
- Sucrose (a.k.a. table sugar) = fructose + glucose
- Lactose (a.k.a. dairy sugar) = galatose + glucose
sugar-phosphate
defined as carbohydrates to which a phosphate group is bound by an ester or an ether linkage,
triose
a 3-carbon sugar
Compare and contrast the synthesis of polypeptides, nucleic acids and polysaccharides from
monomeric units.
- A condensation reaction occurs between the three hydroxyl groups of glycerol and the carboxyl groups of three fatty acids
- This reaction forms a triglyceride (and three molecules of water)
- The bond between the glycerol and the fatty acids is an ester linkage
- When one of the fatty acids is replaced by a phosphate group and phospholipid is formed
- Hydrolysis reactions will, in the presence of water, break these molecules down into their constituent subunits
cellulose
a polymer of β-glucose monomers that serves as a structural polysaccharide in plants
