Bio 1: Module 1 Launchpad HW Questions
Which amino acid would, when incorporated into a polypeptide chain (not at the N or C terminus), make the charge of the polypeptide more positive? a. Arginine b. Aspartate c. Alanine d. Serine e. Cysteine
a. Arginine
Which statement about the flow of genetic information is true? a. DNA encodes information that is transcribed into RNA, and RNA encodes information that is translated into proteins. b. DNA encodes information that is translated directly to proteins, without any intermediaries. c. Proteins encode information that can be translated into RNA, and RNA encodes information that can be transcribed into DNA. d. Proteins encode information that is used to produce other proteins of the same amino acid sequence. e. RNA encodes information that is transcribed into DNA, and DNA encodes information that is translated into proteins.
a. DNA encodes information that is transcribed into RNA, and RNA encodes information that is translated into proteins.
What type of chemical bond connects the two carbon atoms in the molecule: H3C-CH3? a. Nonpolar covalent bond b. Asymmetric bond c. Polar covalent bond d. Hydrogen bond e. Double covalent bond
a. Nonpolar covalent bond
If the codon is 5′-GAA-3′, then the corresponding anticodon is a. 5′-CUU-3′. b. 3′-CTT-5′. c. 5′-GAA-3′. d. 3′-CUU-5′. e. 3′-GAA-5′.
d. 3′-CUU-5′.
The start codon is near the _______ end of the mRNA, and this corresponds with the _______ terminus of the polypeptide. a. 5′; C b. 3′; N c. 3′; C d. 5′; N e. 3′; T
d. 5′; N
What is the sequence of the complementary strand of RNA made from the template DNA sequence below? 5'-CAG CGG TTC GCT GAA GTC-3' a. 5′-GUC GCC AAG CGA CUU CAG-5′ b. 5′-CGG CGA TCG AAG TCG CTT-5′ c. 3′-GTC GCC AAG CGA CTT CAG-5′ d. 5′-GTC GCC AAG CGA CTT CAG-3′ e. 3′-GUC GCC AAG CGA CUU CAG-5′
e. 3′-GUC GCC AAG CGA CUU CAG-5′
In any sample of double-stranded DNA, _______ percent of the bases are purines. a. 10 b. The amount depends upon the organism from which the DNA came. c. 100 d. 25 e. 50
e. 50
Which protein is predicted to be most resistant to denaturation by heat? a. A protein with many internal hydrogen bonds b. A protein with no proline residues in its primary structure c. A protein with no quaternary structure d. A protein with a very short polypeptide chain e. A protein with many internal disulfide bonds
e. A protein with many internal disulfide bond
Where would the leucine side chain most likely be found in a protein dissolved in water? a. In the interior of the protein in contact with polar side chains b. On either the interior or the exterior of the protein c. In the interior of the protein in contact with water d. On the exterior of the protein e. In the interior of the protein in contact with nonpolar side chains
e. In the interior of the protein in contact with nonpolar side chains
Which substance is likely to contain the highest percentage of double bonds in the hydrocarbon chains of its triglycerides? a. Lard b. Butter c. Beef fat d. Pork fat e. Olive oil
e. Olive oil
The primary structure of proteins is the _______. The primary structure contains the information necessary for the formation of a secondary structure, including the _______ and the _______. Secondary structure of proteins is stabilized by the formation of _______ bonds. a. amino acid sequence; α helix; β pleated sheet; hydrogen b. amino acid sequence; α helix; β pleated sheet; peptide c. α helix; amino acid sequence; β pleated sheet; hydrophobic d. β pleated sheet; α helix; amino acid sequence; hydrogen e. amino acid sequence; β pleated sheet; α helix; disulfide
a. amino acid sequence; α helix; β pleated sheet; hydrogen
During the formation of a peptide linkage, a(n) _______ is formed. a. molecule of water b. ionic bond c. disulfide bridge d. hydrophobic bond e. hydrophilic bond
a. molecule of water
RNA differs from DNA in that a. the pentose sugar of DNA has one less oxygen atom. b. the pentose sugar of DNA has one more oxygen atom. c. the nitrogenous bases of DNA have one less oxygen atom. d. RNA has phosphate groups, while DNA does not. e. the nitrogenous bases of DNA have one more oxygen atom.
a. the pentose sugar of DNA has one less oxygen atom.
Which statement is true? a. A single covalent bond involves 1 electron. b. A double covalent bond involves 4 electrons. c. A double covalent bond involves 8 electrons. d. A triple covalent bond is formed among 3 atoms. e. A triple covalent bond involves 12 electrons.
b. A double covalent bond involves 4 electrons.
How does the ionic compound magnesium chloride form? a. A magnesium atom loses one electron, a chlorine atom gains one electron, and an ionic bond forms between the chloride ion and the magnesium ion. b. A magnesium atom loses two electrons, two chlorine atoms each gain one electron, and an ionic bond forms between each chloride ion and the magnesium ion. c. Two magnesium atoms each lose one electron, two chlorine atoms each gain one electron, and an ionic bond forms between each chloride ion and each magnesium ion. d. A chlorine atom loses one electron, a magnesium atom gains one electron, and an ionic bond forms between the chloride ion and the magnesium ion. e. Two chlorine atoms each lose one electron, a magnesium atom gains two electrons, and an ionic bond forms between each chloride ion and the magnesium ion.
b. A magnesium atom loses two electrons, two chlorine atoms each gain one electron, and an ionic bond forms between each chloride ion and the magnesium ion.
Two polypeptide chains have the same amino acid composition and molecular weight, yet only one binds to a cell membrane receptor. Several possible scenarios have been listed to explain these observations. Which is the only plausible one? a. The two chains fold into different three-dimensional shapes because the polypeptides were made by two different organisms. b. The two chains fold into different three-dimensional shapes because the sequences of amino acids differ in the chains. c. One chain is longer than the other chain, causing the polypeptides to fold into different shapes. d. One chain was synthesized in a laboratory, while the other was synthesized in a bacterium, causing differences in the final structures of the proteins. e. One chain has bond linkages connecting amino acids that differ from the bond linkages in the other chain.
b. The two chains fold into different three-dimensional shapes because the sequences of amino acids differ in the chains.
The two strands of a DNA double helix can be separated with relative ease because a. phosphodiester bonds between DNA and complementary RNA bases are relatively weak. b. hydrogen bonds between nitrogenous bases are relatively weak. c. phosphodiester bonds between nitrogenous bases are relatively weak. d. hydrogen bonds between sugars and phosphates of nucleotides are relatively weak. e. phosphodiester bonds between sugars and phosphates of nucleotides are relatively weak.
b. hydrogen bonds between nitrogenous bases are relatively weak.
Tertiary and quaternary structures share all of the following properties except a. van der Waals interactions. b. multiple subunits. c. disulfide bridges. d. hydrogen bonding. e. ionic interactions.
b. multiple subunits.
What is the sequence of the complementary strand of DNA given the template DNA sequence below? 5'-CGG GAC CTT GCA GAA GCT-3' a. 5′-CGA GGC GTC AAC TCG CTT-3′ b. 3′-CGG AGC CTT GCT GAA GCT-5′ c. 3′-GCC CTG GAA CGT CTT CGA-5′ d. 5′-GCC TCG GAA CGT CTT CGA-3′ e. 3′-GCC UCG GAA CGT CUU CGA-5′
c. 3′-GCC CTG GAA CGT CTT CGA-5′
Which amino acid does not have a charged R group? a. Lysine b. Arginine c. Asparagine d. Glutamic acid e. Histidine
c. Asparagine
Five statements describing various properties of DNA are given. Which statement can be used to explain how DNA is able to serve as an informational molecule? a. DNA strands contain the pentose sugar deoxyribose and four different nitrogenous bases, including two purines and two pyrimidines. b. A DNA molecule is double-stranded, with the two strands held together by hydrogen bonds. c. DNA molecules vary in the sequences of bases present in the nucleotides making up their linear chains. d. DNA molecules consist of two complementary polynucleotide chains that run in opposite directions. e. DNA is a polymer of nucleotides bonded together through phosphodiester bonds.
c. DNA molecules vary in the sequences of bases present in the nucleotides making up their linear chains.
_______ are sequences of DNA that are transcribed into RNA. a. Nucleotides b. Genomes c. Genes d. Amino acids e. Primers
c. Genes
Which covalent bond is most polar? a. Nitrogen-oxygen b. Carbon-oxygen c. Hydrogen-oxygen d. Nitrogen-hydrogen e. Carbon-hydrogen
c. Hydrogen-oxygen
What type of chemical bond connects the carbon and oxygen atoms in the molecule: H3C-OH? a. Nonpolar covalent bond b. Asymmetric bond c. Polar covalent bond d. Hydrogen bond e. Hydrophobic interaction
c. Polar covalent bond
The transfer of information from DNA to RNA occurs during _______, while the transfer of information from RNA to protein occurs during _______. a. transcription; transfection b. translation; transfection c. transcription; translation d. translation; elongation e. translation; transcription
c. transcription; translation
Experiments have shown that DNA with a higher G + C content requires a higher temperature to disrupt its double helix than DNA with a higher A + T content. Which statement explains this observation? a. G and C fit together better than A and T. b. The sugar-phosphate bonds in the backbone are stronger in DNA with a higher G + C content. c. The covalent bonds between G and C are stronger than those between A and T. d. G-C pairs form three hydrogen bonds, whereas A-T pairs form just two hydrogen bonds. e. The two chains assume a parallel orientation when the A + T content is higher.
d. G-C pairs form three hydrogen bonds, whereas A-T pairs form just two hydrogen bonds.
Glycogen molecules can vary greatly in size, yet all glycogen molecules perform the same function. Proteins can also vary greatly in size; however, proteins also vary greatly in function. Which statement best explains this difference between glycogen and proteins? a. Glycosidic bonds link the monomers that make up glycogen, whereas peptide bonds link the monomers that make up proteins. b. The monomers making up glycogen are characterized by their many hydroxyl (-OH) groups, whereas the monomers making up proteins are characterized by their amino (-NH2) and carboxyl (-COOH) groups. c. The monomers making up glycogen can convert between ring structures and straight-chain forms, whereas the monomers making up proteins do not undergo these changes. d. Glycogen molecules are composed of one type of monomer, whereas proteins consist of twenty different monomers with different properties. e. Glycogen molecules are highly branched in structure, whereas proteins consist of long, unbranched polymer chains.
d. Glycogen molecules are composed of one type of monomer, whereas proteins consist of twenty different monomers with different properties.
Which statement about RNA is false? a. RNAs are produced by transcription. b. Transfer RNA functions in translation. c. DNA codes for mRNA, tRNA, and rRNA. d. Messenger RNAs are produced on ribosomes. e. Ribosomal RNA functions in translation.
d. Messenger RNAs are produced on ribosomes.
Which level(s) of protein structure would be destroyed by the addition of a denaturing reagent? a. Primary, secondary, and tertiary b. Secondary only c. Tertiary only d. Secondary and tertiary e. Primary only
d. Secondary and tertiary
Which statement about the addition of new nucleotides onto a nucleic acid is true? a. The nucleotides are joined by a disulfide linkage. b. Nucleic acids grow in the 3′-to-5′ direction. c. The phosphate on the new nucleotide joins to the nitrogenous base on the existing chain. d. The phosphate on the new nucleotide and the pentose on the existing chain undergo a condensation reaction. e. The phosphate on the new nucleotide joins to the 3′ carbon of the sugar on the existing chain.
d. The phosphate on the new nucleotide and the pentose on the existing chain undergo a condensation reaction.
How does synthesis of a triglyceride compare with synthesis of a disaccharide? a. Both syntheses produce the same number of water molecules. b. Two more water molecules are produced during synthesis of a disaccharide. c. One more water molecule is produced during synthesis of a triglyceride. d. Two more water molecules are produced during synthesis of a triglyceride. e. One more water molecule is produced during synthesis of a disaccharide.
d. Two more water molecules are produced during synthesis of a triglyceride.
A peptide bond forms between a(n) _______ group on one molecule and a(n) _______ group on the other molecule. a. amino; R b. carboxyl; R c. hydrogen; carboxyl d. amino; carboxyl e. R; hydrogen
d. amino; carboxyl
An amino acid can be classified by the a. number of amino groups it contains. b. number of peptide bonds it can form. c. number of central carbon atoms it contains. d. characteristics of its side chains, or R groups. e. number of disulfide bridges it can form.
d. characteristics of its side chains, or R groups.
A single carbon atom can bond a total of _______ hydrogen atoms, and the outer shell of each hydrogen atom then contains _______ electrons. a. two; two b. two; four c. four; four d. four; two e. eight; two
d. four; two
The "antiparallel relationship" of the two strands of DNA refers to a. which strand begins with a purine and which strand begins with a pyrimidine. b. the view at one end of the molecule—one strand has an A wherever the other has a T, and one has a G wherever the other has a C. c. the twisted configuration of the strands. d. the alignment of the strands, such that one strand starts with a 3′ carbon and the other starts with a 5′ carbon. e. the alternative branching pattern of the strands.
d. the alignment of the strands, such that one strand starts with a 3′ carbon and the other starts with a 5′ carbon.
Palmitic acid: 16C, 0 double bonds Stearic acid: 18C, 0 double bonds Oleic acid: 18C, 1 double bond Linoleic acid: 18C, 2 double bonds A triglyceride contains glycerol bonded to three stearic acid residues. The molecule that is likely to have a melting point closest to that of this triglyceride is a triglyceride containing a. one palmitic acid chain, one oleic acid chain, and one linoleic acid chain. b. two palmitic acid chains and one linoleic acid chain. c. three oleic acid chains. d. three palmitic acid chains. e. one palmitic acid chain and two oleic acid chains.
d. three palmitic acid chains.
Which statement is false? a. Covalent bonds can be polar or nonpolar depending on whether the atoms in the bond share electrons equally or unequally. b. Hydrogen bonds form between or within molecules. c. Ionic attractions and hydrogen bonds are noncovalent interactions involving differences in charge. d. van der Waals forces are so weak that they have no significant importance in molecular interactions. e. Hydrophobic molecules tend to aggregate together.
d. van der Waals forces are so weak that they have no significant importance in molecular interactions.
Vegetable oil is composed of long-chain hydrocarbon molecules. Vegetable oil and water do not mix but form separate layers. Which statement describes the interactions between molecules in this case? a. The water molecules and the hydrocarbon molecules interact with their own kind through hydrogen bonding, but they do not interact with each other. b. The water molecules and the hydrocarbon molecules interact with their own kind through hydrophilic interactions, but they do not interact with each other. c. The water molecules and the hydrocarbon molecules interact with their own kind through hydrophobic interactions, but they do not interact with each other. d. The water molecules interact through hydrophobic interactions, and the hydrocarbon molecules interact through hydrophilic interactions. e. The water molecules interact through hydrophilic interactions, and the hydrocarbon molecules interact through hydrophobic interactions.
e. The water molecules interact through hydrophilic interactions, and the hydrocarbon molecules interact through hydrophobic interactions.
Lipids differ from polysaccharides in that they a. store energy. b. have important structural roles. c. contain carbon. d. can aggregate. e. are nonpolar.
e. are nonpolar.
The magnesium chelatase protein has quaternary structure. This means that magnesium chelatase a. has fourfold symmetry. b. binds to the surface of membranes. c. forms part of a quadruple complex. d. changes over time. e. is composed of subunits.
e. is composed of subunits.
Starch and glycogen, which are both polysaccharides, differ in that starch _______, while glycogen _______. a. is a structural material found in plants and animals; forms external skeletons in animals b. is the main energy storage in animals; is a temporary compound used to store glucose c. is the main component for plant structural support; is an energy source for animals d. is a temporary compound used to store glucose; is a highly stable compound that stores complex lipids e. is the principal energy storage compound of plants; is the main energy storage in animals
e. is the principal energy storage compound of plants; is the main energy storage in animals
Butter is solid at room temperature yet liquid at higher temperatures because a. butter is more saturated at room temperature. b. loss of chaperone molecules allows for the separation of the monomers. c. heat causes formation of double bonds in the fatty acid molecules. d. addition of the milk protein helps the fat molecules aggregate at room temperature. e. van der Waals forces holding the fat molecules together are broken.
e. van der Waals forces holding the fat molecules together are broken.
