18 Questions
What enzyme is needed to break down maltose into two glucose units?
Maltase
Which disaccharide is known as milk sugar?
Lactose
What are the components of sucrose?
Alpha glucose + beta fructose
Which enzyme is needed to break lactose into an equimolar mixture of galactose and glucose?
Lactase
What type of linkage does sucrose have?
Alpha-1,2 (beta)
Which carbohydrate contains three to ten monosaccharide units bonded together?
Oligosaccharides
What is the main carbohydrate found in the seeds and roots of plants?
Starch
Which type of glycosidic bonds are present in amylopectin?
Alpha-1,4 and alpha-1,6
What is used to test for the presence of starch in solution?
Iodine
Which of the following is a homopolysaccharide?
Starch
In which form does amylose exist?
Linear form (alpha 1,4)
Which polysaccharide is commonly found in the exoskeleton of arthropods?
Chitin
Which polysaccharide is stored in animals and has a branched structure similar to amylopectin but is much more extensively branched?
Glycogen
Which substance, found in nearly all plants, provides support and rigidity to plant stems and cell walls?
Cellulose
What is the main structural element in animal exoskeletons and is the second most abundant naturally occurring polysaccharide?
Chitin
What gives cotton its fibrous nature as it is almost pure in cotton (95%) and is about 50% present in wood?
Cellulose
In what form are polysaccharides stored in humans, specifically in liver cells and muscle cells?
Glycogen
Which polysaccharide is broken down through acid or enzymatic hydrolysis to glucose monomers, resulting in the disappearance of its blue-black color?
Starch
Study Notes
Carbohydrates
- Starch breaks down into glucose monomers through acid or enzymatic hydrolysis, resulting in the loss of its blue-black color.
Glycogen
- Glycogen is a polysaccharide stored in animals, similar to starch in plants, with a branched structure.
- It is composed of alpha-glucose units with alpha 1,4 and alpha 1,6 bonds.
- Liver and muscle cells are the storage sites for glycogen in humans.
- Glycogen has a highly branched structure with up to 1,000,000 glucose units.
Structural Polysaccharides
- Cellulose is a polysaccharide found in plant cell walls and animal exoskeletons, providing support and rigidity.
- It is composed of beta-glucose units with beta-1,4-glycosidic bonds.
- Cellulose is found in high concentrations in the "woody" portions of plants.
- Cotton is almost pure cellulose (95%), and wood is about 50% cellulose.
Chitin
- Chitin is a polysaccharide found in the exoskeletons of crustaceans and insects, and in the cell walls of fungi.
- It is composed of N-acetyl-D-glucosamine (NAG) units with beta-1,4-glycosidic bonds.
- Chitin is the second most abundant naturally occurring polysaccharide.
Disaccharides
- Maltose is a disaccharide produced when starch breaks down, composed of alpha-glucose units with alpha-1,4 bonds.
- Maltose is broken down into glucose units by the enzyme maltase.
- Lactose is a disaccharide found in milk, composed of beta-galactose and glucose units with beta-1,4 bonds.
- Lactose is broken down into galactose and glucose by the enzyme lactase.
- Sucrose is a disaccharide found throughout the plant kingdom, composed of alpha-glucose and beta-fructose units with alpha-1,2 bonds.
- Sucrose is broken down into glucose and fructose by the enzyme sucrase.
Oligosaccharides
- Oligosaccharides are carbohydrates with three to ten monosaccharide units bonded by glycoside linkages.
- Raffinose is a trisaccharide found in onions, cabbage, and other vegetables, composed of galactose, glucose, and fructose.
- Stachyose is a tetrasaccharide found in vegetables, composed of galactose, galactose, glucose, and fructose.
Polysaccharides
- Polysaccharides are carbohydrates with many monosaccharide units bonded by glycosidic linkages.
- Homopolysaccharides are composed of only one type of monosaccharide monomer.
- Heteropolysaccharides are composed of more than one type of monosaccharide monomer.
- Parameters used to describe polysaccharides include the identity of the monosaccharide repeating unit, the length of the polymer chain, the type of glycosidic linkage, and the degree of branching.
Storage Polysaccharides
- Starch is a polysaccharide used as an energy source in cells, composed of alpha-glucose units with alpha-1,4 bonds.
- Amylose is the linear form of starch, making up 20-25% of starch.
- Amylopectin is the branched form of starch, making up 75-80% of starch.
- Iodine is used to test for the presence of starch in solution, resulting in a dark blue-black color.
Test your knowledge on Stachyose, a carbohydrate containing galactose, glucose, and fructose, and Polysaccharides, polymers made up of multiple monosaccharide units. Explore concepts such as homopolysaccharides and heteropolysaccharides.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
