Bio 2170 launchpad questions exam 1
Which one of the following represents the pH of a solution with the highest concentration of hydrogen ions? 1.0 4.5 7.0 9.1 11.5
1.0
Molecules made primarily of carbon and hydrogen are called hydrocarbons. How many hydrogen atoms are present in the following molecule? A hydrocarbon chain of five carbon atoms with one double bond and the rest single bonds. 6 8 10 12
10
Actively transcribed regions of eukaryotic chromatin have a diameter of approximately: 30 nanometers. 10 microns. 1400 nanometers. 10 nanometers. 2 nanometers.
10 nanometers.
Molecules made primarily of carbon and hydrogen are called hydrocarbons. How many hydrogen atoms are present in the following molecule? A five-carbon hydrocarbon molecule with four of the carbons linked by a single covalent bond, and with the fifth carbon attached by a single bond as a branch to the second carbon in the chain. 6 8 10 12
12
Molecules made primarily of carbon and hydrogen are called hydrocarbons. How many hydrogen atoms are present in the following molecule? A hydrocarbon chain of five carbons joined to each other by single covalent bonds. 6 8 10 12
12
Alpha helices are stabilized by hydrogen bonds between amino acids that are ______ residues apart. 2 4 10 20 100
4
How many electron orbitals does a carbon atom possess? 2 4 5 6 12
5
amino end - Met-Ile-Gly-Ser-Ile-His - carboxyl end
5'-ATGATCGGATCGATCCAT-3' 3'-TACTAGCCTAGCTAGGTA-5' Which of the following is the correct polypeptide assembled by the translation of the mRNA produced by the transcription of this DNA molecule? amino end - Met-Ile-Gly-Ser-Ile-His - carboxyl end amino end - Tyr-Leu-Ala-Arg-Lue-Val - carboxyl end carboxyl end - Met-Ile-Gly-Ser-Ile-His - amino end carboxyl end - Tyr-Leu-Ala-Arg-Lue-Val - amino end
5'-ATGATCGGATCGATCCAT-3' 3'-TACTAGCCTAGCTAGGTA-5' Which of the following is the correct mRNA produced from the transcription of this DNA molecule? 5'-AUGAUCGGAUCGAUCCAU-3' 3'-AUGAUCGGAUCGAUCCAU-5' 5'-UACUAGCCUAGCUAGGUA-3' 3'-UACUAGCCUAGCUAGGUA-5'
5'-AUGAUCGGAUCGAUCCAU-3'
In a nucleotide, the phosphate is attached to the ____________ carbon of the sugar, and the base is attached to the ____________ carbon of the sugar. 5'; 3' 3'; 5' 2'; 3' 5'; 1' 1'; 5'
5'; 1'
Molecules made primarily of carbon and hydrogen are called hydrocarbons. How many hydrogen atoms are present in the following molecule? A ring of six carbon atoms held together by alternating single and double bonds. 6 8 10 12
6
14C is an isotope of carbon that possesses: 6 protons, 6 neutrons, and 2 electrons. 6 protons, 8 neutrons, and 6 electrons. 8 protons, 6 neutrons, and 2 electrons. 6 protons, 2 neutrons, and 6 electrons. 6 protons, 8 neutrons, and 2 electrons.
6 protons, 8 neutrons, and 6 electrons.
Approximately how many bases of RNA are hydrogen bonded to DNA within an RNA polymerase in E. coli? 14 8 35 10 4
8
Molecules made primarily of carbon and hydrogen are called hydrocarbons. How many hydrogen atoms are present in the following molecule? A hydrocarbon chain of five carbon atoms with two double bond and two single bonds. 6 8 10 12
8
Which one of the following is least likely to be found in a nucleotide? A nitrogen-containing base A five-carbon sugar All of the answer choices are equally likely to be found in a nucleotide. A side chain One or more phosphate groups
A side chain
Which one of the following activities would least likely be found in a topoisomerase? Adding nucleotides to the end of a DNA strand Cutting a phosphodiester linkage Reforming phosphodiester linkages Topoisomerases are equally likely to perform all of these functions. Inducing or relaxing twists in double-stranded DNA
Adding nucleotides to the end of a DNA strand
Which one of the following statements about DNA is incorrect? DNA typically exists in cells as a double helix. There are 10 base pairs per turn in a helical DNA molecule. DNA has a diameter of approximately 2 nanometers. The strands in DNA wrap around each other in a helix that coils to the right. All of the statements about DNA are correct.
All of the statements about DNA are correct.
If a mutation rendered the signal recognition particle nonfunctional, what would be the most obvious effect on the cell? All proteins normally secreted by the cell would remain partially formed and attached to the endoplasmic reticulum. Translation would not be completed for most proteins. No proteins would arrive at their proper destinations within the cell. Proteins destined for the nucleus would remain in the cytosol. All proteins normally secreted by the cell would remain in the cytosol.
All proteins normally secreted by the cell would remain in the cytosol.
Which one of the following is a critical region of a tRNA molecule? Amino acid attachment site Anticodon loop Stop codon Amino acid attachment site and anticodon loop All of these choices are correct.
Amino acid attachment site and anticodon loop
Which one of the following amino acids is most likely to participate in hydrogen bonding with water? Alanine Asparagine Leucine Phenylalanine Valine
Asparagine
Which one of the following steps in translation is not part of the elongation phase? Movement of the ribosome three bases closer to the 3' end of the mRNA Ejection of an uncharged tRNA from the E site of the ribosome Peptide bond formation Binding of initiator tRNA to AUG start codon Introduction of a charged tRNA into an unoccupied A site of the ribosome
Binding of initiator tRNA to AUG start codon
Which of the following ranks the elements carbon, sodium, calcium, and iodine in order of greatest abundance in living organisms? C → Na → Ca → I I → Ca → Na → C I → C → Ca → Na C → Ca → Na → I
C → Ca → Na → I
Proteins that do not refold properly after being heated generally require the assistance of which one of the following types of molecules in vivo? Polymerases Ribosomes Enhancers Chaperones Transferases
Chaperones
Which one of the following represents an actual Watson-Crick base pair with the largest number of hydrogen bonds? Cytosine and guanine Adenine and cytosine Cytosine and thymine Thymine and guanine Adenine and thymine
Cytosine and guanine
Which of the following statements about a carbon-carbon double bond is correct? Each of the two carbons is capable of bonding to three other atoms. The double bond allows free rotation of the molecule at the bond position. The double bond is longer than a corresponding carbon-carbon single bond. Double bonds can be found in cyclical structures. None of these statements about carbon-carbon double bonds is correct.
Double bonds can be found in cyclical structures.
Which one of the following would least likely be used during the initiation phase of translation? Elongation factors tRNA Small ribosomal subunits Initiation factors mRNA
Elongation factors
Which of the following ranks the elements carbon, sodium, calcium, and iodine in order of decreasing number of valence electrons? C → Na → Ca → I I → Ca → Na → C I → C → Ca → Na C → Ca → Na → I
I → C → Ca → Na
Which of the following ranks the elements carbon, sodium, calcium, and iodine in order of decreasing number of electrons? C → Na → Ca → I I → Ca → Na → C I → C → Ca → Na C → Ca → Na → I
I → Ca → Na → C
Which of the following ranks the elements carbon, sodium, calcium, and iodine in order of decreasing number of energy shells/levels? C → Na → Ca → I I → Ca → Na → C I → C → Ca → Na C → Ca → Na → I
I → Ca → Na → C
Which of the following ranks the elements carbon, sodium, calcium, and iodine in order of decreasing number of protons? C → Na → Ca → I I → Ca → Na → C I → C → Ca → Na C → Ca → Na → I
I → Ca → Na → C
A phosphodiester bond is formed between: a fatty acid and a glycerol molecule. two amino acids. a base and a sugar. a 3' phosphate and a 5' hydroxyl group. a 5' phosphate and a 3' hydroxyl group.
a 5' phosphate and a 3' hydroxyl group.
The three-dimensional shape of a protein is determined by the primary, secondary, tertiary, and in many cases, the quaternary structure of the protein. The following sentence is taken from scientific articles on protein structure. Choose the level of protein structure that applies best to the sentence. "Peptide bonds form between the monomers." Primary Secondary Tertiary Quaternary
Primary
Which one of the following amino acids has its R-group covalently linked to the amino group of the amino acid? Glycine Serine Cysteine Glutamic acid Proline
Proline
The three-dimensional shape of a protein is determined by the primary, secondary, tertiary, and in many cases, the quaternary structure of the protein. The following sentence is taken from scientific articles on protein structure. Choose the level of protein structure that applies best to the sentence. "Hydrogen bonds between peptide 'backbone' amino groups and carboxyl groups of one polypeptide and the R-groups of another polypeptide, contribute to the overall function of the protein." Primary Secondary Tertiary Quaternary
Quaternary
Which one of the following statements about RNA is incorrect? The nucleotide at the 5' end of an RNA molecule is typically a nucleoside triphosphate. RNA molecules can form base pairs within a single strand. RNA molecules are capable of evolving their enzymatic activity over time. RNA is usually found in double-stranded form, just like DNA. RNA molecules are typically shorter than DNA molecules.
RNA is usually found in double-stranded form, just like DNA.
Which one of the following statements about RNA is correct? All of these choices are correct. RNA is a more stable molecule than DNA. RNA uses the same pyrimidine bases as DNA. RNA has the same 5-carbon sugars as DNA. RNA uses the same purine bases as DNA.
RNA uses the same purine bases as DNA.
Which one of the following is not a component of a nucleosome core particle? Histone H3 Ribosomes Histone H4 Approximately 150 base pairs of DNA Histone H2B
Ribosomes
The three-dimensional shape of a protein is determined by the primary, secondary, tertiary, and in many cases, the quaternary structure of the protein. The following sentence is taken from scientific articles on protein structure. Choose the level of protein structure that applies best to the sentence. "Hydrogen bonds between peptide backbone components form a distinct helical structure." Primary Secondary Tertiary Quaternary
Secondary
Which one of the following would least likely be used during translation? Initiation factors Release factors Sigma factors Elongation factors All of the answer choices would be equally likely to be used during translation.
Sigma factors
The three-dimensional shape of a protein is determined by the primary, secondary, tertiary, and in many cases, the quaternary structure of the protein. The following sentence is taken from scientific articles on protein structure. Choose the level of protein structure that applies best to the sentence. "Disulfide bonds formed between cysteines stabilize the overall structure of this protein isolated from the bacterium." Primary Secondary Tertiary Quaternary
Tertiary
The three-dimensional shape of a protein is determined by the primary, secondary, tertiary, and in many cases, the quaternary structure of the protein. The following sentence is taken from scientific articles on protein structure. Choose the level of protein structure that applies best to the sentence. "There are extensive ionic interactions between positively charged R-groups and negatively charged R-groups on the polypeptide." Primary Secondary Tertiary Quaternary
Tertiary
The three-dimensional shape of a protein is determined by the primary, secondary, tertiary, and in many cases, the quaternary structure of the protein. The following sentence is taken from scientific articles on protein structure. Choose the level of protein structure that applies best to the sentence. "There are hydrogen bonds between peptide backbone components that form neither an α-helix nor a β-pleated sheet." Primary Secondary Tertiary Quaternary
Tertiary
In which of the following ribosomal sites is there complete codon-anticodon base pairing? The A site only The P site only The A site and the P site The P site and the E site The A site, the P site, and the E site
The A site and the P site
Where does the energy come from to add a uracil to the 3' end of a transcript? The hydrolysis of pyrophosphate from the incoming UTP molecule The hydrolysis of a single phosphate from the incoming UTP molecule The energy released by allowing the uracil to complementary base pair with an adjacent thymine The cell's supply of ATP The hydrolysis of all three phosphate groups from the incoming UTP molecule
The hydrolysis of pyrophosphate from the incoming UTP molecule
Which one of the following cellular processes occurs in the nucleus of a eukaryote? Transcription RNA processing Translation Transcription and RNA processing All of these choices are correct.
Transcription and RNA processing
An initiator codon in E. coli is identified by locating: a promoter sequence. the 5' cap structure. a Shine-Dalgarno sequence. a terminator sequence from the previous gene. an origin of replication.
a Shine-Dalgarno sequence.
Which of the following best describes the hydrophilic component of cholesterol? a hydroxyl group only a group of four planar rings and a hydroxyl group a phosphate group and a chemical group called choline a single hydrocarbon tail a phosphate group only
a hydroxyl group only
In the context of ribosomes, the Svedberg value 60S most likely represents: an intact bacterial ribosome. an intact eukaryotic ribosome. a large bacterial ribosomal subunit. a large eukaryotic ribosomal subunit. a small eukaryotic ribosomal subunit.
a large eukaryotic ribosomal subunit.
Which of the following would be considered an integral membrane protein? Select all correct choices. a protein attached to a phospholipid via ionic bonding with the head group of the lipid molecule a protein capable of diffusing throughout the cytoplasm of a cell a protein attached to a transmembrane protein via hydrogen bonding a protein with its N-terminus in the cytoplasm and its C-terminus in the extracellular space
a protein with its N-terminus in the cytoplasm and its C-terminus in the extracellular space
Proteins can be used for which one of the following cellular roles? Cell signaling Structural support Biological catalysis Cell communication All of these choices are correct.
all
The structural diversity of carbon-based molecules is based upon which of the following properties? the ability of carbon to form four covalent bonds the ability of those bonds to rotate freely the orientation of those bonds in the form of a tetrahedron None of these choices is correct. All of these choices are correct.
all
Which one of the following codons is capable of terminating translation? UAG UAA UGA UAG and UAA All of these choices are correct.
all
X-ray crystallography was used to determine the structure of: cholesterol. vitamin B12. myoglobin. insulin. All of these choices are correct.
all
Miller and Urey's initial simulation resulted in the formation of which one of the following? DNA glucose RNA phospholipids amino acids
amino acids
The sodium/potassium pump is an example of: channel-mediated diffusion. a symporter. an antiporter. passive transport. None of these choices is correct.
an antiporter.
In order for bilayers to form spontaneously, the pH of the solution should be: highly acidic. moderately basic. approximately neutral. highly basic. moderately acidic.
approximately neutral.
Complete the matching exercise below by choosing the correct strength of each bond type in aqueous solution. 1. Covalent bond 2. Hydrogen bond 3. Ionic bond a. Weak b. Strong
b. covalent a.ionic a.hydrogen
Complete the matching exercise below by choosing the correct description of each bond type in aqueous solution. 1. Covalent bond 2. Hydrogen bond 3. Ionic bond a. An interaction of a hydrogen atom and an electronegative atom. b. An interaction between oppositely charged ions. c. Electrons shared by atoms.
c. covalent a. hydrogen b.ionic
The most abundant organic molecule in nature is: cholesterol. water. cellulose. aquaporin. ATP.
cellulose.
If you isolate a single nucleotide from a nucleic acid chain and determine that the nitrogenous ring structure is cytosine, you could say with certainty that the nucleotide could have come from: DNA but not RNA. RNA but not DNA. either DNA or RNA. neither DNA nor RNA. double-stranded DNA but not single-stranded DNA
either DNA or RNA.
Triacylglycerols are used primarily for: energy storage. information storage. cell membrane biosynthesis. biological catalysis. movement.
energy storage.
In eukaryotes, activator proteins bind to ___________; generalized transcription factors bind to ____________. promoters; terminators promoters; enhancers DNA polymerases; RNA polymerases terminators; RNA polymerases enhancers; promoters
enhancers; promoters
True or False: the first cells were surrounded by a membrane composed largely of lipids synthesized by intracellular proteins.
false
Exposure of purified phospholipids to water results in the spontaneous formation of: lipid bilayers. triacylglycerols. steroids. polypeptides. carbohydrates.
lipid bilayers.
Specific types of lipids assemble into defined areas of a biological membrane referred to as: sphingopatches. cholesterol plugs. plaques. lipid rafts. biomembrane aggregation regions (BARs)
lipid rafts.
Which one of the following biological polymers is defined by a physical property rather than a chemical structure? proteins lipids monosaccharides nucleic acids polysaccharides
lipids
Certain meteorites have been examined and found to carry samples of which one of the following? lipids amino acids photosynthetic bacteria lipids and amino acids lipids, amino acids, and photosynthetic bacteria
lipids and amino acids
Some amino acids are coded by just one codon. Which of the following amino acids fall into this category? (More than one answer may be correct.) methionine tyrosine tryptophan serine leucine
methionine tryptophan
RNA molecules are transported from the nucleus to the cytoplasm in eukaryotes through: budding off of the nuclear envelope. nuclear pore complexes. passive diffusion. sodium/potassium channels. aquaporins.
nuclear pore complexes.
rRNAs are transcribed in the: cytoplasm. nucleus. nucleolus. mitochondria. endoplasmic reticulum.
nucleolus.
Sutherland and colleagues demonstrated the synthesis of which one of the following under conditions thought to resemble those of early Earth? nucleotides amino acids phospholipids nucleic acid chains polypeptides
nucleotides
Which one of the following elements would most likely have bonding properties similar to nitrogen (N)? Consult the periodic table in Figure 2.3 if necessary. carbon (C) silicon (Si) phosphorous (P) sulfur (S) oxygen (O)
phosphorous (P)
Which of the following is moved from one side of a lysosomal membrane to the other via a transport channel? Select all correct choices. protons broken-down macromolecules enzymes capable of breaking down macromolecules being delivered from the Golgi apparatus protons and broken-down molecules
protons and broken-down molecules
Which one of the following RNA types is most abundant in mammalian cells? tRNA rRNA snRNA miRNA mRNA
rRNA
The molecule currently being investigated as a possible means of synthesis of the first proteins is: mRNA. DNA. tRNA. rRNA. aminoacyl tRNA synthetases.
rRNA.
Some amino acids are coded by as many as six different codons. Which of the following amino acids fall into this category? (More than one answer may be correct.) methionine tyrosine tryptophan serine leucine
serine leucine
The component(s) of E. coli RNA polymerase responsible for promoter recognition is(are) referred to as: the mediator complex. an enhancer. the TATA box. transcription factors. sigma factor.
sigma factor.
Using the periodic table in Figure 2.3, determine which one of the following elements would be found in least abundance in a living cell. hydrogen (H) sodium (Na) phosphorous (P) zinc (Zn) silicon (Si)
silicon (Si)
When a mixture of debris from killed virulent bacteria and living non-virulent bacteria are injected into mice: the mice survive for a period of a few weeks and then die from an unrelated illness. half the mice are killed and the other half survive. the mice are killed because the non-virulent bacteria are transformed into virulent bacteria. the mice survive because none of the living bacteria are virulent. the mice are killed because the virulent bacteria are revived.
the mice are killed because the non-virulent bacteria are transformed into virulent bacteria.
Which one of the following is not considered part of the cytoplasm? the cytoskeleton the Golgi apparatus None of these choices is considered part of the cytoplasm. the nucleus the endoplasmic reticulum
the nucleus
A protein with an internal signal sequence is most likely to be located in: the cytoplasm. the nucleus. a mitochondrion. a chloroplast. the extracellular space.
the nucleus.
True or false: although monosaccharides can exist in linear form, virtually all cellular monosaccharides are found in circular form.
true
true or False: multiple ribosomes can be translating protein from a single mRNA simultaneously in a eukaryote, but the mRNAs being translated are monocistronic.
true