CHM105: Chapter 15
What are carbohydrates primarily used for in the body?
a) Structural support
b) Energy storage
c) Oxygen transport
d) DNA synthesisWhat elements make up carbohydrates?
a) Carbon, nitrogen, oxygen
b) Carbon, hydrogen, oxygen
c) Hydrogen, oxygen, sulfur
d) Carbon, phosphorus, hydrogenCarbohydrates are also known as:
a) Amino acids
b) Lipids
c) Saccharides
d) NucleotidesHow are carbohydrates produced in nature?
a) Protein synthesis
b) Photosynthesis in plants
c) Hydrolysis of lipids
d) Cellular respirationThe process in which carbohydrates are oxidized in living cells to produce energy is called:
a) Photosynthesis
b) Hydrolysis
c) Cellular respiration
d) Fermentation
Types of Carbohydrates
What is the simplest type of carbohydrate?
a) Disaccharide
b) Polysaccharide
c) Monosaccharide
d) OligosaccharideA carbohydrate with two monosaccharide units is called a:
a) Monosaccharide
b) Disaccharide
c) Polysaccharide
d) TrisaccharideWhat are polysaccharides composed of?
a) Two sugar units
b) Many sugar units
c) Amino acids
d) LipidsMonosaccharides with an aldehyde group are classified as:
a) Aldoses
b) Ketoses
c) Disaccharides
d) PolysaccharidesMonosaccharides with a ketone group are classified as:
a) Aldoses
b) Ketoses
c) Disaccharides
d) Polysaccharides
Classification of Monosaccharides
A monosaccharide with six carbon atoms and a ketone group is called a:
a) Aldohexose
b) Ketohexose
c) Aldopentose
d) KetopentoseWhat is an example of an aldohexose?
a) Fructose
b) Glucose
c) Ribose
d) DihydroxyacetoneThe sugar found in RNA is:
a) Glucose
b) Ribose
c) Fructose
d) Sucrose
Chirality & Stereoisomers
A carbon atom bonded to four different atoms or groups is called:
a) Achiral
b) Chiral
c) Linear
d) PlanarWhat are stereoisomers?
a) Isomers with different bonding arrangements
b) Isomers with the same bonding sequence but different spatial arrangements
c) Isomers with different molecular formulas
d) Isomers that are superimposableEnantiomers are:
a) Isomers that have identical mirror images
b) Isomers that are non-superimposable mirror images
c) Isomers that differ in bonding arrangements
d) Isomers with identical physical propertiesThe D and L designation of monosaccharides is based on:
a) The position of the —OH group on the highest-numbered carbon
b) The presence of an aldehyde or ketone group
c) The length of the carbon chain
d) The total number of hydrogen atoms
Fischer & Haworth Projections
In a Fischer projection, the most oxidized group is placed:
a) At the bottom
b) At the center
c) At the top
d) On the leftThe Haworth structure of glucose forms a:
a) Five-membered ring
b) Six-membered ring
c) Linear structure
d) Branched polymerWhich monosaccharide forms a five-membered ring in its Haworth structure?
a) Glucose
b) Galactose
c) Fructose
d) Maltose
Chemical Properties of Monosaccharides
What is a reducing sugar?
a) A sugar that forms dimers
b) A sugar that can be oxidized to form a carboxylic acid
c) A sugar that cannot be oxidized
d) A sugar that lacks a hydroxyl groupWhich reagent is used to test for reducing sugars?
a) Benedict’s solution
b) Iodine
c) Silver nitrate
d) Sodium hydroxideWhich sugar is NOT a reducing sugar?
a) Glucose
b) Fructose
c) Sucrose
d) GalactoseWhat is formed when a monosaccharide is reduced?
a) Sugar acid
b) Sugar alcohol
c) Ketone
d) Polysaccharide
Disaccharides & Polysaccharides
What monosaccharides make up lactose?
a) Glucose + fructose
b) Glucose + galactose
c) Glucose + glucose
d) Fructose + galactoseWhat type of glycosidic bond does maltose have?
a) α(1→4)
b) β(1→4)
c) α(1→6)
d) β(1→2)Which polysaccharide is used for energy storage in animals?
a) Cellulose
b) Amylose
c) Amylopectin
d) GlycogenWhat polysaccharide is the major structural component of plant cell walls?
a) Glycogen
b) Cellulose
c) Starch
d) MaltoseWhy can humans digest starch but not cellulose?
a) Starch is branched, while cellulose is linear
b) Humans have enzymes to break α-glycosidic bonds but not β-glycosidic bonds
c) Cellulose lacks glucose molecules
d) Starch dissolves in water, while cellulose does notWhat is the difference between amylose and amylopectin?
a) Amylose is branched, while amylopectin is unbranched
b) Amylose is unbranched, while amylopectin is branched
c) Amylopectin is used for structure, while amylose is used for energy storage
d) Amylopectin contains only ketose sugars