17 Questions
Which enzyme is responsible for interconverting D & L isomers?
Racemases
What is the main characteristic that differentiates epimers?
Different configuration at one specific carbon atom
Which glucose derivative is used in the reduction of intracranial pressure?
Mannitol
Which deoxy sugar is an essential component of DNA?
Deoxyribose
In optical isomerism, which term denotes a compound that rotates plane-polarized light to the left?
Levoratory
Which sugar alcohol is known to cause cataracts in diabetics?
Sorbitol
Which biomolecule is most abundant on earth?
Carbohydrates
What is a key function of glucose in the bloodstream?
Glycogen storage
What type of simple sugar is considered the simplest form of carbohydrate?
Monosaccharides
Which function(s) of carbohydrates is associated with hyaluronic acid?
Lubrication
What suffix is commonly associated with carbohydrates?
-ose
Which condition is related to carbohydrate metabolism?
Fructosuria
Which of the following sugars is a pentose?
D-Ribose
Which organ does NOT primarily rely on glucose?
Liver
Which sugar has the molecular formula of $CH_2OH-CO-CH_2OH$?
Dihydroxyacetone
Which sugar has two hydroxyl groups attached to the same carbon?
Dihydroxyacetone
Which configuration of D-Galactose at the second carbon is correct?
H-C-OH
Study Notes
Isomerism
- D and L isomers of monosaccharides exist due to the orientation of the penultimate carbon atom (CH2OH)
- Racemases can interconvert between D and L isomers
- Most monosaccharides are D isomers
Epimerism and Anomers
- Epimerism occurs when one carbon is configured differently
- Anomers form when a ring structure is formed, creating an additional asymmetric carbon (anomeric carbon)
- Anomeric carbon can be either α (OH and CHOH on opposite sides) or β (OH and CHOH on the same side)
Deoxy Sugars
- Lack of an oxygen atom in the sugar molecule
- Deoxyribose is found in DNA
- 2-deoxyglucose is an inhibitor of glucose metabolism and is used in blood group antigens
Sugar Alcohols (Alditols)
- Derivatives of aldoses and ketoses with reduced carbonyl groups
- Examples include sorbitol, mannitol, and dulcitol
- Sugar alcohols are mild sweet tasting and have various biological functions
Aldonic Acid and Uronic Acid
- Mild oxidation of aldoses forms aldonic acid
- Uronic acid is formed by enzymatic oxidation of aldoses at C6
- Aldaric acid is formed by strong oxidation of aldoses at C1 and C6
Carbohydrates
- Most abundant biomolecule on earth
- Can be synthesized by plants from CO2 and H2O
- Have various functions in the body, including fuel storage, cell-cell recognition, and immune response
Classification of Carbohydrates
- Monosaccharides: simplest carbohydrates with a single building block
- Disaccharides: composed of two building blocks
- Polysaccharides: composed of ten or more building blocks
- Classification based on the number of carbon atoms in the molecule
Monosaccharides
- Simplest carbohydrates with a single building block
- Can be classified based on the number of carbon atoms in the molecule
- Examples include D-Glucose, D-Mannose, and D-Galactose
D-Sugars
- Examples of D-sugars include D-Glyceraldehyde, D-Ribose, D-Arabinose, D-Xylose, D-Glucose, D-Mannose, and D-Galactose
Sugars by Number of Carbons
- Trioses: 3-carbon sugars, including glyceraldehyde and dihydroxyacetone
- Tetroses: 4-carbon sugars, including erythrose and erythrulose
- Pentoses: 5-carbon sugars, including ribose and ribulose
- Hexoses: 6-carbon sugars, including glucose, galactose, mannose, and fructose
- Heptoses: 7-carbon sugars, including sedoheptulose
Learn about D and L isomers, epimerism, and anomers in monosaccharides, including their formation and properties.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free