Which polysaccharide does not have a repeating unit of glucose?
amylopectin
cellulose
chitin
amylose
2 points
QUESTION 2
In which of the following sugars is the bonding between monosaccharide units “head-to head” rather than “head-to-tail”?
cellobiose
maltose
lactose
sucrose
2 points
QUESTION 3
Which of the following sets of elements is a possible composition for a standard amino acid?
carbon, hydrogen, oxygen, and sulfur
carbon, hydrogen, nitrogen, and sulfur
carbon, hydrogen, and nitrogen
carbon, hydrogen, oxygen, nitrogen, and sulfur
2 points
QUESTION 4
R-group interaction between which of the following pairs of amino acids produces a disulfide bond?
cysteine-cysteine
proline-proline
alanine-glycine
valine-methionine
2 points
QUESTION 5
In which of the following pairs of carbohydrates are both members of the pair monosaccharides?
fructose and glucose
lactose and arabinose
sucrose and maltose
cellobiose and cellulose
2 points
QUESTION 6
Which of the following statements concerning fatty acids is incorrect?
Some fatty acids needed in the human body must be obtained from food because they cannot be synthesized with the body.
Fatty acids are rarely found in the free state in nature.
At least 16 carbon atoms must be present in the carbon chain of a fatty acid.
Double bonds present in fatty acids are almost always in a cis-configuration.
2 points
QUESTION 7
The designation “monounsaturated” applies to which of the following fatty acids?
oleic acid (18:1)
palmitic acid (16:0)
arachidonic acid (20:4)
butyric acid (4:0)
2 points
QUESTION 8
Phospholipids are composed of
a glycerol, two fatty acids and a phosphate group attached to an alcohol
membrane lipids
a glycerol and three fatty acids
a glycerol, a phosphate group, a protein and a fatty acid
2 points
QUESTION 9
What effect does unsaturation in fatty acids have on the melting point of the structure?
no effect
the more unsaturated, the straighter the molecule, so the higher the melting point
the more unsaturated, the more bends in the molecule, so the higher the melting point
the more unsaturated, the more bends in the molecule, so the lower the melting point
2 points
QUESTION 10
The joining together of two amino acids to form a dipeptide involves the reaction between
two amide groups
an amino group and an alpha-carbon
an amino group and a carboxyl group
an alpha-carbon and a hydroxyl group
2 points
QUESTION 11
What are some of the interactions that are responsible for tertiary structure?(Mark all correct answers.)
alpha helix
hydrogen bonds
covalent disulfide bonds
beta sheet
2 points
QUESTION 12
How do the standard amino acids differ from one another?
in whether or not the amino group is chiral
in whether or not the carboxyl group is chiral
in the number of chiral carbon atoms between the carboxyl group and the amino group
in the identity of the R group (side chain)
2 points
QUESTION 13
Saponification of a fat or oil
produces fatty acid salts
increases the degree of fatty acid unsaturation
increases the melting point
decreases the melting point
2 points
QUESTION 14
Which of the following monosaccharides is a ketohexose?
glucose
fructose
ribulose
ribose
2 points
QUESTION 15
In which of the following pairs of fatty acids does the first listed acid have a higher melting point than the second listed acid?
16:2 acid and 16:0 acid
21:0 acid and 17:0 acid
17:3 acid and 17:0 acid
17:3 acid and 20:0 acid
2 points
QUESTION 16
Which structure is not affected by denaturation?
quaternary
tertiary
secondary
primary
2 points
QUESTION 17
Which of the following is a distinguishing characteristic between fats and oils?
physical state at room temperature
alcohol component present in their structures
type of linkage between fatty acids and the alcohol present
odor
2 points
QUESTION 18
Which of the following substances will produce both glucose and galactose when hydrolyzed?
lactose
maltose
sucrose
glycogen
2 points
QUESTION 19
The membrane lipid cholesterol is structurally composed of
a glycerol and three fatty acids
a fused ring structure
phospholipids
fatty acids
2 points
QUESTION 20
What is the difference between an essential fatty acid and a nonessential fatty acid?
an essential fatty acid can not be synthesized by the body
a nonessential can not be synthesized by the body
the structure of the essential fatty acid includes only saturated fatty acids
nonessential fatty acids are not needed by the body
2 points
QUESTION 21
Which protein is the most abundant in humans?
hemoglobin
myoglobin
collagen
keratin
2 points
QUESTION 22
Which of the following proteins are globular?
collagen
keratin
fibrin
myoglobin
2 points
QUESTION 23
The bond that links the two monosaccharides of a disaccharide together is a carbon-carbon-oxygen bond.
True
False
2 points
QUESTION 24
The major structural difference between cellulose and starch is found in the
identity of the monosaccharide units present
ring size of the monosaccharide units present
linkages between the monosaccharide units present
handedness of the monosaccharide units present
2 points
QUESTION 25
Which of the following terms correctly describes the relationship between D-fructose and L-fructose?
enantiomers
epimers
diastereomers
cis-trans isomers
2 points