20 Questions
What is the characteristic feature of sucrose among the sugars mentioned?
Both anomeric carbon atoms are fixed in a glycosidic linkage
What is the primary function of glycogen in animals?
To store energy in a compact form
What is the difference between starch and glycogen?
Glycogen is more branched than starch
What is the primary component of cell walls in plants?
Cellulose
What is the function of cellulose in the diet?
To stimulate the intestinal movement and prevent constipation
What is the characteristic feature of amylose?
It is an unbranched polymer of α(1,4) glucose
What type of bond forms between two monosaccharides to create a disaccharide?
glycosidic bond
Which of the following is an example of a disaccharide?
Sucrose
What is the term for the carbon atom in a monosaccharide that forms a cyclic ring?
anomeric carbon
What is the term for a monosaccharide that contains a reactive carbonyl group?
Reducing sugar
What is the term for a monosaccharide that cannot be readily oxidized?
Non-reducing sugar
How many member ring is formed in a monosaccharide?
Six
What is the characteristic of monosaccharides that contain 2 monosaccharide units?
They are classified as disaccharides.
Which of the following is an example of a polysaccharide?
Glycogen
What is the characteristic of polysaccharides in terms of their composition?
They contain hundreds of monosaccharide units.
What is the difference between a disaccharide and a polysaccharide?
Disaccharides are smaller, while polysaccharides are larger.
Which of the following is NOT a characteristic of polysaccharides?
They are composed of only one monosaccharide unit.
What is the characteristic of disaccharides in terms of their composition?
They contain exactly two monosaccharide units.
What is the relationship between disaccharides and polysaccharides?
Disaccharides are a type of polysaccharide.
Which of the following is an example of a polysaccharide found in plants?
Starch
Study Notes
Carbohydrates
- Carbohydrates are defined as C:H:O in a 1:2:1 ratio, and can be represented by the general formula CH2OH.
- They can be classified into three main categories: monosaccharides, disaccharides, and polysaccharides.
Monosaccharides
- Monosaccharides are the simplest carbohydrates, and can be further classified into aldoses and ketoses.
- Examples of monosaccharides include glyceraldehyde (a triose), erythrose (a tetrose), ribose (a pentose), and glucose, galactose, and fructose (hexoses).
- Monosaccharides are optically active, contain at least one asymmetric carbon (chiral center), and can exist as stereoisomers.
- Stereoisomers of monosaccharides can be classified into enantiomers, epimers, and anomers.
Enantiomers, Epimers, and Anomers
- Enantiomers are non-superimposable mirror images of each other, and can exist in D or L conformation.
- Epimers are sugar molecules that differ in configuration at only one of several chiral centers.
- Anomers are cyclic ring structures that can be formed by aldhyde or ketone groups, and can exist in α or β configurations.
Disaccharides
- Disaccharides are formed by the combination of two monosaccharides through a glycosidic bond.
- Examples of disaccharides include sucrose (glucose + fructose), lactose (galactose + glucose), and maltose (glucose + glucose).
Reducing and Non-Reducing Sugars
- Reducing sugars contain a reactive carbonyl group, are readily oxidized, and can reduce metal ions.
- Non-reducing sugars, such as sucrose, have both anomeric carbon atoms fixed in a glycosidic linkage, and are not readily oxidized.
Polysaccharides
- Polysaccharides are larger, containing hundreds of monosaccharides.
- They can be classified into homopolysaccharides (composed of a single monosaccharide building block) and heteropolysaccharides (composed of different building blocks).
- Examples of polysaccharides include glycogen, starch, and cellulose.
Glycogen and Starch
- Glycogen is the major form of stored carbohydrate in animals, composed of α(1,4) glucose linkages, and highly branched by α(1,6) linkages every 8-10 residues.
- Starch is the major form of stored carbohydrate in plants, similar in structure to glycogen but less extensively branched.
Cellulose
- Cellulose is a structural polysaccharide composed of long, straight, non-branching chains of β-D-glucose linked by β-(1-4) glucosidic bonds.
- It is insoluble in water, cannot be digested by humans, and plays an important role in the diet by increasing the bulk of stool and stimulating intestinal movement.
This quiz covers the different types of carbohydrates, including reducing and non-reducing sugars, polysaccharides, and their classifications.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
