chapter 5 pearson mastering biology
A function of cholesterol that does not harm health is its role _____
as a component of animal cell membranes
Which polysaccharide is an important component in the structure of many animal and fungal cells?
chitin
structure is the sequence of amino acids in a protein.
primary
The structural level of a protein least affected by a disruption in hydrogen bonding is the
primary level.
If you wanted to show the 3-dimensional shape of a protein, including all of the atoms composing it, you should use a
space filling
The secondary structure of a protein results from _____.
hydrogen bonds
Which of these is a source of lactose?
milk
Polymers that contain sugars ...
(a) may store hereditary information. (b) may store energy. (c) may protect cells.
The presence of many C-C and C-H bonds causes fats to be ...
(a) rich in energy.(b) insoluble in water.
How many fatty acids are in a phospholipid?
2
How many molecules of water are required for the hydrolyzation of a polymer that is 22 monomer-long cellulose molecule?
21
If a strand of DNA has the nitrogen base sequence 5'-ATTTGC-3', what will be the sequence of the matching strand?
3'-TAAACG-5'
Which of the following pairs of base sequences could form a short stretch of a normal double helix of DNADNA?
5′-ATGC-3′5′-ATGC-3′ with 5′-GCAT-3′
If a DNA double helix is 100 nucleotide pairs long and contains 25 adenine bases, how many guanine bases does it contain?
75
Which of the following statements about the formation of polypeptides from amino acids is true?
A bond forms between the carboxyl functional group of one amino acid and the amino functional group of the other amino acid.
Which molecule is less soluble in water--a fat or a phospholipid? Why?
A fat molecule is less soluble in water because it has three non-polar fatty acids and no polar or charged head like a phospholipid has.
Which molecule is a nucleotide?
ATP
Select the statement that is incorrect.
All carbohydrates have the general formula Cn(H2O)nCn(H2O)n
Which complex carbohydrate contains only a-1,4-glycosidic linkages?
Amylose
Which of the following is not attached to the central carbon atom in an amino acid?
An oxygen
Triglycerides vary with respect to the number of ...
C atoms in the tails.(c) double bonds in the tails.
The molecular formula for glucose is C6H12O6C6H12O6. What would be the molecular formula for a polymer made by linking ten glucose molecules together by dehydration reactions?
C60H102O51
Which part of an amino acid is always acidic?
Carboxyl functional group
Plant cell walls consist mainly of __________.
Cellulose
_____ is the most abundant organic compound on Earth.
Cellulose
Which of the following complex carbohydrates is listed with its correct function?
Cellulose: structural component of plant cell walls
You have just sequenced a new protein isolated from mice and observe that sulfur-containing cysteine residues occur at regular intervals. "This finding is most consistent with which of the following claims about the protein?
Cysteine residues are involved in disulfide bridges that help form tertiary structure.
The flow of genetic information in a cell goes from _____. See Concept 5.5 (Page)
DNA to RNA to protein
Which of the following best compares dehydration reactions and hydrolysis?
Dehydration reactions assemble polymers; hydrolysis reactions break polymers apart.
Why can humans digest starch but not cellulose?
Humans have enzymes that can hydrolyze the α-glycosidic linkages of starch but not the β-glycosidic linkages of cellulose.
The label on a container of margarine lists "hydrogenated vegetable oil" as the major ingredient. Which of the following options describes the property of hydrogenated vegetable oil?
It is solid at room temperature.
Which of the following statements about lipids is true?
Lipids mix poorly with water.
What do fats, steroids, and waxes have in common?
Low solubility in water.
Which of the following statements about monosaccharide structure is true?
Monosaccharides can be classified according to the spatial arrangement of their atoms.
The building blocks ( monomers) of nucleic acid molecules are called __________.
Nucleotides
Which monomers make up RNA?
Nucleotides
A hydrophobic amino acid R group (side group) would be found where in a properly folded protein?
On the inside of the folded chain, away from water molecules
Which polysaccharide contains a modified monosaccharide?
Peptidoglycan
There are four levels of protein structure. These figures show primary, secondary, tertiary, and quaternary protein structure. Which level(s) of protein structure may be stabilized by covalent bonds?
Primary, tertiary and quaternary levels of protein structure
Which polymers are composed of amino acids?
Proteins
These figures show the four levels of protein structure: primary, secondary, tertiary, and quaternary structure. Which level of protein structure is characteristic of some, but not all, proteins?
Quaternary level of protein structure
What structural difference accounts for the functional differences between starch and cellulose?
Starch and cellulose differ in the glycosidic linkages between their glucose monomers.
Which feature of large biological molecules explains their great diversity?
The many ways that monomers of each class of biological molecule can be combined into polymers
What could happen if a mutation in a gene caused a hydrophobic amino acid in a polypeptide to be replaced by a hydrophilic amino acid?
The new amino acid would not form the same interactions with hydrophobic R groups, and the protein's shape would likely be affected.
Enzymes that break down DNADNA catalyze the hydrolysis of the covalent bonds that join nucleotides together. What would happen to DNADNA molecules treated with these enzymes?
The phosphodiester linkages of the polynucleotide backbone would be broken.
Which of the following statements describes the interaction of water molecules with phospholipids?
The polar heads interact with water; the nonpolar tails do not.
Which of the following statements is an accurate description of proteins?
The primary structure of a protein is the order of amino acids in a polypeptide, as coded for in the DNA of a gene.
Which of the following statements is correct regarding starch and cellulose?
They are polymers of glucose.
What do DNA, proteins, and fats have in common?
They contain carbonyl groups.
Which of the following statements correctly describes "saturated fats"?
They contain more hydrogen than unsaturated fats that consist of the same number of carbon atoms.
Which of the following features of cooking oil and gasoline (hydrocarbons) identifies why the molecules are NOT amphipathic?
They do not have a polar or charged region.
Which statement about unsaturated fats is true?
They have double bonds in their fatty acid chains.
True or false? Enzymes in the digestive tract catalyze hydrolysis reactions.
True
True or false? Peptidoglycan is a polysaccharide found only in bacteria.
True
Dr. Haxton told one of his students, "To move in the bloodstream, fats need the help of phospholipids." What would a good student say?
Yes. Nonpolar molecules aren't compatible with water.
Glycogen is _____.
a polysaccharide found in animals
Proteins are polymers of _____.
amino acids
People who are lactose intolerant cannot extract energy from milk because ________.
an enzyme is not functioning correctly
Starch is composed of which of the following?
branched amylopectin and unbranched amylose
Which of the following has been associated with atherosclerosis and should be eliminated from one's diet for health reasons?
butter, liver, and kidney organ meat
A simple sugar is composed of equal parts carbon and water, which gave rise to the general name of any sugar as a
carbohydrate
Which of the following categories includes all others in the list?
carbohydrate
The term insoluble fiber on food packages refers to which of the following molecules?
cellulose
Which of these is a polysaccharide?
cellulose
Palm coconut oils are more like animal fats than other plant oils. Because they __________ than other plant oils, they may contribute to cardiovascular disease.
contain fewer double bonds
What is another name for a condensation reaction?
dehydration
When two amino acid monomers are positioned so that the carboxyl group of one is adjacent to the amino group of the other, they can be joined through a ___ reaction.
dehydration
Lactose, the sugar in milk, is a ___, because it can be split into two monosaccharides.
disaccharide
In fat synthesis,________and fatty acids combine to make fats plus________.
glycerol; water
The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are in the αα form. Which of the following could amylase break down?
glycogen, starch, and amylopectin
Sucrose is formed when glucose is joined to fructose by a(n) _____.
glycosidic linkage
The two strands of a DNA double helix are held together by _____ that form between pairs of nitrogenous bases.
hydrogen bonds
What is the name of the process during which a bond between two monomers is broken?
hydrolysis
What holds phospholipids together in a bilayer formation?
hydrophilic and hydrophobic interactions with water
In the reaction that builds a fat,________ groups react with ________ groups.
hydroxyl; carboxyl
Defensive proteins are manufactured by the _____ system.
immune
A food company hydrogenated a barrel of fat. The treatment ...
made the fat less fluid.
glucose + glucose —> _____ by _____.
maltose + water ... dehydration synthesis
2. A __ cannot be hydrolyzed any further
monosaccharide
The characteristic that all lipids have in common is __________.
none of them dissolves in water
Which of these is rich in unsaturated fats?
olive oil
Which of these does NOT contain a structural protein?
ovalbumin
What type of bond joins the monomers in a protein's primary structure?
peptide
Tertiary structure is NOT directly dependent on _____.
peptide bonds. Peptide bonds link together the amino acids of a protein's primary structure.
A nucleotide is composed of a(n) _____.
phosphate group, a nitrogen-containing base, and a five-carbon suga
A carbohydrate that yields many monosaccharides when hydrolyzed is a
polysaccharide
The four main categories of large biological molecules present in living systems are __________.
proteins, nucleic acids, carbohydrates, and lipids
structure is the result of two or more protein subunits assembling to form a larger, biologically active protein complex.
quarternary
. If you wanted to show the 3-dimensional shape of a protein, including the backbone structure, folds, and coils, you should use a
ribbon model
structure describes the alpha-helices and beta-sheets that are formed by hydrogen bonding between backbone atoms located near each other in the polypeptide chain.
secondary
Some regions of a polypeptide may coil or fold back on themselves. This folding is called __________, and the coils or folds are held in place by __________.
secondary structure, hydrogen bonds
If you wanted to show a generalized protein in which the focus is on the protein's function rather than its structure, you should use a
simple shape
. If you wanted to show the general shape of a protein, along with some important functional details such as folds and coils, you should use a
simplified
structure is achieved when a protein folds into a compact, three-dimensional shape stabilized by interactions between side-chain R groups of amino acids.
tertiary
The most unsaturated fats have ...
the most double bonds.
The difference between an aldose sugar and a ketose sugar is ________.
the position of the carbonyl group
A dehydration reaction (or condensation reaction) is the process in which __________.
water molecules are produced as a polymer formed from monomers
If you wanted to show the 3-dimensional shape of a protein by showing the amino acid side chains and their interactions, you should use a
wireframe model
Maltose is a disaccharide that can easily be digested into glucose molecules. Which type of glycosidic linkage connects glucose molecules in maltose
α 1-4
