Podcast
Questions and Answers
Carbohydrates can only be classified as monosaccharides based on the number of sugar units.
Carbohydrates can only be classified as monosaccharides based on the number of sugar units.
False (B)
Aldoses are monosaccharides that contain a ketone group.
Aldoses are monosaccharides that contain a ketone group.
False (B)
A trisaccharide is classified as a polysaccharide because it contains three sugar units.
A trisaccharide is classified as a polysaccharide because it contains three sugar units.
False (B)
The general formula for monosaccharides is C_n(H2O)_n.
The general formula for monosaccharides is C_n(H2O)_n.
Signup and view all the answers
A ketotetrose is a monosaccharide that contains four carbon atoms and an aldehyde group.
A ketotetrose is a monosaccharide that contains four carbon atoms and an aldehyde group.
Signup and view all the answers
A substance with an asymmetric carbon atom can only exhibit optical activity.
A substance with an asymmetric carbon atom can only exhibit optical activity.
Signup and view all the answers
The formula for calculating the number of isomers for a substance containing n asymmetric carbon atoms is $2^n$.
The formula for calculating the number of isomers for a substance containing n asymmetric carbon atoms is $2^n$.
Signup and view all the answers
Enantiomers are a type of isomerism that involves compounds with identical spatial configurations.
Enantiomers are a type of isomerism that involves compounds with identical spatial configurations.
Signup and view all the answers
L and D forms of monosaccharides are classified based on the position of the -OH group on the last carbon atom.
L and D forms of monosaccharides are classified based on the position of the -OH group on the last carbon atom.
Signup and view all the answers
Anomers are isomers formed by changing the position of the hydroxyl group on any carbon atom in the monosaccharide.
Anomers are isomers formed by changing the position of the hydroxyl group on any carbon atom in the monosaccharide.
Signup and view all the answers
Glucose is classified as an aldohexose.
Glucose is classified as an aldohexose.
Signup and view all the answers
Dihydroxyacetone is classified as an aldopentose.
Dihydroxyacetone is classified as an aldopentose.
Signup and view all the answers
All monosaccharides are soluble in water.
All monosaccharides are soluble in water.
Signup and view all the answers
Ribulose is a type of aldotetrose.
Ribulose is a type of aldotetrose.
Signup and view all the answers
The ability of a substance to rotate the plane polarized light is known as optical activity.
The ability of a substance to rotate the plane polarized light is known as optical activity.
Signup and view all the answers
Erythrose is a ketose sugar.
Erythrose is a ketose sugar.
Signup and view all the answers
D-galactose is classified as a ketohexose.
D-galactose is classified as a ketohexose.
Signup and view all the answers
Optical activity requires the presence of a chiral center in the molecule.
Optical activity requires the presence of a chiral center in the molecule.
Signup and view all the answers
Flashcards
Monosaccharides
Monosaccharides
Simplest carbohydrates, made of one sugar unit. Cannot be broken down further by hydrolysis.
Disaccharides
Disaccharides
Carbohydrates consisting of two sugar units.
Aldoses
Aldoses
Monosaccharides containing an aldehyde group.
Triose
Triose
Signup and view all the flashcards
Carbohydrates general formula
Carbohydrates general formula
Signup and view all the flashcards
Asymmetric Carbon Atom
Asymmetric Carbon Atom
Signup and view all the flashcards
Optical Activity
Optical Activity
Signup and view all the flashcards
Optical Isomerism
Optical Isomerism
Signup and view all the flashcards
Enantiomers
Enantiomers
Signup and view all the flashcards
Anomers
Anomers
Signup and view all the flashcards
Glucose
Glucose
Signup and view all the flashcards
Fructose
Fructose
Signup and view all the flashcards
Pentoses
Pentoses
Signup and view all the flashcards
Study Notes
Carbohydrate Chemistry
- Carbohydrates are aldehyde or ketone derivatives of polyhydric alcohols.
- They serve as a source of energy (e.g., glucose) and structural components in animal and plant cells (e.g., cellulose, chitin).
- Carbohydrates may combine with lipids (glycolipids) or proteins (glycoproteins) and form the ground substance in cell membranes and between tissues.
- Carbohydrates are classified based on the number of sugar units into monosaccharides, disaccharides, oligosaccharides, and polysaccharides.
Monosaccharides
- Monosaccharides are the simplest carbohydrate units.
- They cannot be hydrolyzed into simpler forms.
- Their general formula is C(H₂O)ₙ
- Monosaccharide names end in "-ose."
Monosaccharide Nomenclature
- Aldoses contain an aldehyde group.
- Ketoses contain a ketone group.
Classification of Monosaccharides
- A. Based on the number of carbon atoms:
- Trioses (3 carbons)
- Tetroses (4 carbons)
- Pentoses (5 carbons)
- Hexoses (6 carbons)
- Heptoses (7 carbons)
- B. Based on the functional group:
- Aldoses
- Ketoses
- C. Based on both the functional group and the number of carbons:
- Aldotriose, ketotriose
- Aldotetrose, ketotetrose
- Aldopentose, ketopentose
- Aldohexose, ketohexose
Examples of Monosaccharides
- Aldoses: Glyceraldehyde, Erythrose, Ribose, Glucose, Galactose, Mannose
- Ketoses: Dihydroxyacetone, Xylulose, Ribulose, Fructose
Optical Activity of Monosaccharides
- Optical activity is the ability of a substance to rotate plane-polarized light.
- Monosaccharides exhibit optical activity due to the presence of asymmetric carbon atoms.
- Asymmetric carbon atoms are those bonded to four different groups or atoms.
- Substances containing one asymmetric carbon atom have two isomers
- Substances containing two or more asymmetric carbon atoms can have 2ⁿ isomers, where n is the number of asymmetric carbon atoms.
- Monosaccharides are often classified into D and L isomers based upon the configuration of the asymmetric carbon atom furthest from the carbonyl group.
Monosaccharide Isomerism
- Enantiomers (L and D forms):
- Monosaccharides exist as pairs of enantiomers, distinguished by the position of the hydroxyl group (-OH) attached to the carbon atom adjacent to the last CH₂OH
- Most monosaccharides found in mammals are of the D- configuration.
Cyclic Forms of Monosaccharides
- Pyranose and Furanose Forms:
- Monosaccharides readily exist in ring forms (pyranose for six-membered rings and furanose for five-membered rings).
- Usually more than 99% of glucose in solution exists in a pyranose form.
- Anomers:
- Anomers are isomers that differ in the configuration around the anomeric carbon.
- The anomeric carbon is the carbon atom formed from the carbonyl group during ring closure.
- In aldoses, the anomeric carbon is C-1
- In ketoses, the anomeric carbon is C-2
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge on carbohydrate chemistry, focusing on monosaccharides and their classification. This quiz covers the properties, nomenclature, and significance of carbohydrates in biological systems. Perfect for students studying organic chemistry and biochemistry.
