Exam 1 Quiz Questions
A hydrolysis reaction: A) Usually results in increased entropy. B) Is rarely an enzyme-mediated reaction in cells. C) Tends to occur slowly in a humid environment. D) Is a reaction in which the products have more free energy than the reactants. E) Tends to happen more efficiently at lower temperatures.
A
A peptide bond, established by the polymerization of amino acids is an example of A) A polar covalent bond B) An ionic bond C) H hydrogen bond D) A non polar covalent bond
A
A, B and C are all substrates for Enzyme X. The Km for each substrate is as follows: Substrate A: Km=80mM Substrate B: Km=20mM Substrate C:Km=.01mM A) Enzyme X has a higher affinity for Substrate C than it does for either Substrate A or B B) Enzyme X will not bind effectively to Substrate C C) Vmax will be highest with Substrate A D) Enzyme X has a higher affinity for Substrate A than Substrate B
A
Allosteric activators A) bind away from the active site, causing a conformational change in the active site B) bind to the active site, causing a conformational change in the active site C) bind to the enzyme irreversibly D) resemble the substrate
A
At room temperature, how does cholesterol affect the plasma membrane? A) It reduces the mobility of phospholipids. B) It increases membrane fluidity. C) It decreases the phospholipid head groups from interacting with water. D) It increases the Van der Waals forces between hydrocarbon tails.
A
Conservation of energy, as stated in the first law of thermodynamics means that A) energy can neither be created nor destroyed B) energy can be destroyed but not created C) energy can be created but not destroyed D) energy can both be created and destroyed
A
Exergonic reactions A) have a negative ∆G. B) consume energy. C) have a positive ∆G. D) do not occur spontaneously.
A
How are two monosaccharides in a polysaccharide joined? A) Glycosidic bond B) Ester linkage C) Peptide bond D) Phosphodiester linkage
A
If most chemical reactions are reversible, what is one way to ensure that the biochemical reactions in humans proceed in a forward direction? A) The products of the reactions are quickly consumed by the next reaction. B) Body temperature is kept at a fairly constant level. C) The concentration of products is always very high. D) Specific enzymes are available for each reaction.
A
If the external solution is hypertonic relative to the inside of a cell, what type of water movement will occur? A) Water will move out of the cell via osmosis. B) Water will move into the cell via osmosis. C) Water will not move in or out of the cell. D) Water will move out of the cell via active transport.
A
The sequence of amino acids in a polypeptide chain is called A) primary structure B) quaternary structure C) secondary structure D) tertiary structure
A
What types of secondary structures are commonly found in proteins? A) α helix and β pleated sheet B) α helix and secondary hydrogen bonding C) β pleated sheet and secondary hydrogen bonding D) Hydrogen bonding and quaternary interactions
A
Which of the following is a similarity between desmosomes and tight junctions? A) Proteins are involved that link cells together. B) They allow the passage of large molecules from one cell to another. C) They are only found in epithelial cells. D) They allow the passage of small molecules from one cell to another.
A
Which of the following is true of an enzyme catalyzed reaction? A) The Km of the reaction would change with the addition of a competitive inhibitor. B) The Vmax of the reaction would change with the addition of a competitive inhibitor. C) The rate of the reaction is independent of temperature. D) The transition state free energy would remain unchanged in the presence or absence of enzyme. E) The products always have a higher free energy than the reactants.
A
Which of the following is true of nucleic acid molecules? A) In a double stranded DNA molecule purines hydrogen bond to pyrimidines B) The ribose sugar never has a 2' OH C) A DNA molecule that contains mostly A-T pairs would be more heat resistant than a DNA molecule that contains mostly G-C pairs D) Phosphodiester bonds are formed by hydrolysis reactions for both DNA and RNA E) If you know the amount of adenine in a single strand of RNA, you can determine the amount of thymine in that same strand
A
Which of the following statements about carbohydrates is TRUE? A) The beta glycosidic bond is more stable than the alpha glycosidic bond B) Carbohydrates can freely diffuse across the membrane C) The alpha glycosidic bond is present in most cellulose molecules D) Carbohydrates contain carbon, hydrogen, oxygen and phosphate E) Peptidoglycan is a good energy source for bacterial cells
A
Which of the following statements about the nuclear envelope are true? A) It is continuous with the endomembrane system. B) It is made of a single membrane with nuclear pores. C) It is continuous with the nucleolus. D) It is connected to the plasma membrane.
A
Which of the following statements is true? A) Spontaneous reactions have a negative ∆G. B) Spontaneous reactions occur at a rapid rate. C) Endergonic reactions have a negative ∆G. D) Non-spontaneous reactions only need enzymes for them to proceed forward.
A
Which of the following statements regarding carbohydrates is FALSE? A) The α glycosidic bond is used in the formation of cellulose B) Carbohydrates are polar molecules C) α and β glucose have the same chemical formula D) Carbohydrates contain carbon, hydrogen and oxygen only E) Carbohydrates are added to proteins in the Golgi apparatus of eukaryotic cells
A
Why is receptor mediated endocytosis an appropriate term? A) It starts when extracellular molecules bind to receptors B) It is the first step in formation of a lysosome C) It is the first step in phagocytosis D) It is the first step in autophagy
A
You have discovered a new amino acid whose R-group consists of an unsaturated hydrocarbon chain. What properties would best describe this amino acid R-group: A) Limited capacity to interact with H2O B) No capacity to make chemical interactions C) Great capacity to form hydrogen bonds D) Limited capacity to interact with membranes E) Great capacity to form covalent bonds that would stabilize tertiary structure
A
According to Chargaff's rules, A) G=T B) A=T C) A=C D) T=C
B
Cellulose is A) a plant protein B) a material found in plant cell walls C) composed of monomers of ? glucose monomers D) a material found in plasma membranes
B
Gibb's free energy represents A) the amount of energy consumed in a reaction. B) the energy available to do work. C) the total amount of energy. D) the amount of energy lost as heat.
B
If all of the actin proteins in a cell were to become permanently denatured, which of the following would be directly affected? A) Tight junction formation B) Cytoplasmic streaming C) Production of ATP by mitochondria D) Primary structure of integrin E) Chaperone production
B
If the pH of a solution becomes lower than what is optimal for a specific enzyme, what might occur? A) The enzyme will increase its activity to compensate for the pH change. B) The enzyme will denature and become less active. C) Chaperones will protect the enzyme from the acidic environment such that activity is preserved. D) The environment immediately surrounding the active site will behave as a buffer such that the reaction can continue to proceed.
B
In looking at the following molecules, which would contain polar covalent bonds? 1. COOH 2. O2 3. HCN 4. CH3 5. NH3 A) 1, 2, 3, and 5 only B) 1, 3, and 5 only C) 1 and 3 only D) 2, 3, and 5 only E) 2 and 4 only
B
Monosaccharides are monomeric units of A) Lipids B) Carbohydrates C) Proteins D) Nucleic acids
B
Phospholipids can form lipid bilayers whereas fatty acids do not. What characteristic of phospholipids allows them to form lipid bilayers? A) Phospholipids are largely hydrophobic. B) Phospholipids contain polar head groups. C) Phospholipids contain a long hydrocarbon chain. D) Phospholipids can be unsaturated or saturated.
B
The chemical formula for a six carbon molecule is C6H12O6. What type of molecule is this? A) Protein B) Carbohydrate C) DNA D) RNA
B
When the temperature is lower than optimal for a particular enzyme, why does enzyme activity decrease? Choose the most complete answer. A) There are fewer collisions between the enzyme and reactants. B) There are fewer collisions between enzyme and reactants, and the enzyme's active site is no longer flexible enough to allow the reaction to proceed. C) The enzyme's active site is no longer flexible enough to allow the reaction to proceed. D) There are fewer collisions between enzyme and reactants, the active site is no longer flexible enough to allow the reaction to proceed, and the protein will not be able to maintain proper hydrophobic bonding.
B
Which eukaryotic organelle is responsible for protein sorting and modification? A) The rough endoplasmic reticulum B) The Golgi apparatus C) The lysosome D) The smooth endoplasmic reticulum
B
Which of the following best summarizes the relationship between condensation reactions and hydrolysis reactions? A) condensation reactions break covalent bonds, hydrolysis breaks hydrogen bonds B) condensation assembles polymers and hydrolysis breaks down polymers C) hydrolysis creates monomers and condensation reactions break down polymers D) condensation reactions are the same as hydrolysis reactions
B
Which of the following correctly describes secondary active transport of protons and sugar across a membrane into a cell? A) Protons and sugar move against their concentration gradient using ATP hydrolysis B) Protons move down their concentration gradient while sugar moves against its concentration gradient C) An antiporter carries protons out of the cell against its concentration gradient and sugar into the cell down its concentration gradient using ATP hydrolysis D) Protons and sugar move down their concentration gradient
B
Which of the following correctly pairs the organelle to its function: A) Golgi apparatus; amino acid synthesis B) Smooth ER; lipid and carbohydrate synthesis C) Mitochondria; inner membrane synthesis D) Peroxisome; energy production from oxidation products E) Rough ER; transcription of new RNA molecules
B
Which of the following is NOT, or does NOT contain a monosaccharide? A) Cellulose B) Triglycerides C) Deoxyribose D) RNA E) Peptidoglycan
B
Which of the following is not a classification of amino acids? A) Acidic B) Globular C) Hydrophobic D) Hydrophilic
B
Which of the following is not part of the backbone of an amino acid? A) amino group B) R group C) carboxyl group D) ? carbon
B
Which of the following is part of cell theory? A) Most organisms are multicellular B) All cells contain DNA C) All cells have unique metabolic strategies D) All cells have phospholipid bilayers surrounding their nucleus E) Unicellular organisms can spontaneously arise
B
Which of the following is true of a catabolic reaction? A) It is endergonic B) It leads to increased entropy C) Reactants have a lower free energy than products D) It has a +∆G
B
Which of the following moves molecules across a membrane against a concentration gradient? A) channel mediated facilitated diffusion B) active transport C) simple diffusion D) carrier mediated facilitated diffusion
B
Which of the following statements about competitive inhibitors is false? A) A competitive inhibitor often resembles the natural substrate. B) A competitive inhibitor decreases the Vmax of a reaction. C) A competitive inhibitor binds to the active site. D) A competitive inhibitor increases the Km of the reaction.
B
Which of the following statements is true about allosteric enzymes? A) Allosteric enzymes are regulated when a substance B) Allosteric enzymes can be both negatively and positively regulated. C) Allosteric enzymes can only be negatively regulated. D) Allosteric enzymes can only be positively regulated.
B
Which one of the following is not a function of carbohydrates? A) Energy storage B) Catalysis C) Energy source
B
Which statement is true about a protein's quaternary structure? A) The primary amino acid sequence of a protein is referred to as its quaternary structure B) More than one polypeptide subunit is required. C) Quaternary structures refers to a protein's two dimensional shape D) All polypeptides involved in quaternary structure must be the same
B
You are running an enzyme catalyzed reaction. The Vmax for the reaction is 60 mM/min and the Km is 20 nm substrate. You double the enzyme concentration and run the experiment again. What would you expect your Vmax and Km values to be with increased enzyme? A) Vmax: 60; Km: 20 B) Vmax: 120; Km: 20 C) Vmax:60; Km: 40 D) Vmax:120; Km: 40 E) Vmax: 120; Km:10
B
You are studying a metabolic enzyme that is found in organisms living at extremely high temperatures and an acidic environment. You carry out your reactions on your lab bench at room temperature in water and find that the reaction is quite slow, even though you are able to reach a Vmax. Which of the following is not a good way to increase the rate of the reaction? A) Add more enzyme to the reaction. B) Increase substrate concentration. C) Decrease the pH of the reaction solution. D) Increase the temperature.
B
A common delivery method for getting drugs into cells is to surround the drug with a lipid bilayer called a liposome. How do you think this allows the drugs to enter the cell? A) The liposome cuts a hole in the cell and allows the drug to enter the cell B) The entire liposome and drug complex move into the cell by simple diffusion C) The liposome fuses with the phospholipid bilayer of cells that results in the drug being delivered into the cell D) The drug breaks down the liposome and diffuses into the cell E) The liposome is moved into the cell via active transport using a transporter that all cells have
C
Cohesion of water molecules is due to A) non-polar covalent bonds between hydrogen and carbon. B) polar covalent bonds between hydrogen atoms. C) hydrogen bonding between water molecules. D) water molecules adhering to glass.
C
If a red blood cell is placed in a hypertonic solution, what will happen? A) The red blood cell transports ions out of the cell. B) Nothing C) The red blood cell will shrink. D) The red blood cell will swell
C
In polymerization of nucleic acids, the next incoming nucleotide is added to the _____________ of the previous nucleotide A) 2'-OH B) 3'-phosphate C) 3'-OH D) 5'-phosphate
C
Louis Pasteur sterilized a flask of media and then extended the neck of the flask so that bacteria and other organisms could not fall into the media. Which part of cell theory was he testing? A) That all prokaryotic cells are related to other prokaryotic cell and eukaryotic cells are related to other eukaryotic cells B) That all cells are fundamentally similar to each other C) That all cells come from pre-existing cells D) That some organisms are single-celled microbes while others are multi-cellular E) That cells are the functional unit of life and can do all the things necessary to support life
C
The Tree of Life is based on phylogenetic analysis of _______ A) an organism's DNA B) morphological and phenotypic traits C) small subunit ribosomal RNA D) entire genomes
C
The sequence of a small piece of one strand of DNA is 5' TCGATC 3'. The sequence of the complementary DNA strand would be: A) 3' GATCGA 5' B) 5' AGCTAG 3' C) 3' AGCTAG 5' D) 3' AGCUAG 5' E) 5' AGCUAG 3'
C
There are 3 major domains of life. Cells from which domain(s) have membranes made from phospholipids? A) Bacteria B) Eukarya C) Archaea, Bacteria, and Eukarya D) Mammals E) Archaea
C
What determines the primary structure of a polypeptide? A) The number of polypeptides that make up a protein B) Hydrogen bonds and other interactions between side chains C) Its sequence of amino acids D) Hydrogen bonds that form between carboxyl and amino groups on different residues
C
What is the correct pairing between nucleotide bases? A) A-T and G-U B) A-G and T-C C) A-T and G-C D) A-C and G-T
C
Which functional group is not found in proteins? A) Carboxyl B) Carbonyl C) Phosphate D) Amino
C
Which of the following does not contain DNA? A) Mitochondrion B) Nucleoid C) Peroxisome D) Chloroplast
C
Which of the following is NOT part of cell theory? A) Unicellular organisms arise from preexisting cells B) New cells come from preexisting cells C) Most organisms on Earth are multicellular D) Cells are the functional unit of life E) All organisms are composed of cells
C
Which of the following is an example of primary active transport? A) A small hydrophobic molecule diffuses across the lipid bilayer. B) Water moves down its concentration gradient through aquaporins. C) ATP directly transfers energy to the Na+/K+ pump to transport ions across the membrane. D) Glucose enters a cell using facilitated diffusion.
C
Which of the following is false regarding the Na+/K+ ATPase? A) It causes an electrochemical gradient to be formed across the membrane B) It is an antiporter C) It causes Na+ ion concentration to be high inside the cell D) K+ ions are pumped against their concentration gradient
C
Which of the following is not a difference between RNA and DNA? A) RNA has a hydroxyl (-OH) group at the 2' carbon while DNA has none. B) RNA typically is single stranded while DNA is double stranded Correct Answer C) RNA bases are linked via a phosphodiester linkage while DNA bases are linked via an ester linkage. D) RNA contains the bases A, U, G, and C while DNA uses the bases A, T, G, and C.
C
Which of the following is not an example of an energy transformation? A) A chemical reaction converts the energy in sunlight into the chemical energy in glucose B) The electrical energy flowing through a lightbulb's filament is converted into light and heat C) Sunlight strikes a prism and separates into distinct wavelengths D) A shoe drops, converting potential energy into kinetic energy
C
Which of the following levels of protein structure does not contain hydrogen bonds? A) secondary B) tertiary C) primary D) quaternary
C
Which of the following molecules can easily cross an artificial liposome? A) A polar amino acid B) RNA C) A long-chain fatty acid D) DNA
C
Which of the following organelles harnesses energy in a eukaryotic cell? A) Cytoskeleton B) Golgi apparatus C) Mitochondrion D) Lysosome
C
Which of the following statements about enzymes is not correct? A) Enzymes lower activation energy of a reaction B) Induced fit may occur, whereby the active site of the enzyme may undergo a slight change in shape when substrate binds C) The presence of an enzyme will change the outcome of a reaction D) Enzymes speed up the rate of a chemical reaction
C
Which of the following would you expect to be TRUE of a catalase enzyme isolated from an Archaea living in an acidic pool? A) It would raise the activation energy of a reaction run at basic pH B) It would be completely inactive at any pH above 4.0 C) It would have a lower Km at pH 4 than catalase enzyme isolated from a soil dwelling bacteria D) It would have a lower Km at pH 8.0 than at pH 5.0
C
Which statement about the Cell Theory is false? A) Cells are the smallest entities that have all the properties of life B) Cells arise from pre-existing cells C) All organisms are multicellular D) In the most basic sense, all cells are similar
C
Which type of bond or interaction is most sensitive to changes in pH? A) covalent B) hydrogen C) ionic D) Van der waals interactions
C
'Sweetness' is the name of a hypothetical enzyme that breaks down complex carbohydrates in the cytoplasm. You find that sweetness requires 2 identical subunits to be active as an enzyme. Thus, A) Sweetness requires only primary, secondary and tertiary structure to be active B) Sweetness requires only primary and secondary structure to be active C) Sweetness likely has mostly hydrophobic amino acids in its active site D) Sweetness requires primary, secondary, tertiary and quaternary structure to be active E) Sweetness likely was synthesized by ribosomes in the rough ER
D
A bacterium that normally grows at room temperature (~ 25 °C) suddenly finds itself in a hot spring that is 75 °C? Which of the following is most likely to be true for that bacterium? A) Its proteins will lose their primary structure. B) Its nucleic acid strands will lose their polarity. C) Its peptide bonds will likely break. D) Its proteins will lose their quaternary structure. E) Its membranes will be covalently linked together for stabilization.
D
All of the following are true of protein denaturation except that it A) can be caused by changes in temperature B) can be caused by changes in pH C) results in a change in protein conformation D) is always irreversible
D
An enzyme is able to metabolize two similar sugars. The Km for sugar A is 15 mM while the Km for sugar B is 20 mM. Which statement is true about this information? A) The enzyme has a higher affinity for sugar B. B) The enzyme is more efficient at metabolizing sugar B than sugar A. C) The concentration of sugar A needed to reach Vmax is 15 mM. D) The enzyme is more efficient at metabolizing sugar A than sugar B.
D
Are enzymes proteins? A) All of them are, and all proteins are enzymes. B) All of them are, but not all proteins are enzymes. C) No. Proteins are not enzymes. D) Some of them are, but not all proteins are enzymes.
D
Hydrogen bonds can be formed in each of the following situations EXCEPT: A) between two protein subunits interacting in a quaternary structure B) between nitrogenous bases in a double stranded DNA molecule C) between water (H2O) and ammonia (NH3) D) between cholesterol and a hydrocarbon chain in an animal membrane E) between two amino acids in an alpha-helix
D
If a red blood cell is place in a hypotonic solution, what will happen? A) The red blood cell will shrink. B) Nothing. C) The red blood cell transports ions into the cell. D) The red blood cell will swell.
D
If an atom has a charge of +2, which of the following must be true? A) It has at least three valence electrons B) It has less protons than it has electrons C) It has two more protons than neutrons D) It has less electrons than it has protons
D
In a small stretch of a double stranded DNA molecule, there are a total of 8 nucleotide base pairs. If 3 of the bases were guanines and 5 of the bases were adenines, how many hydrogen bonds would be holding this molecule together? A) 16 B) 21 C) 8 D) 19
D
Non-competitive inhibitors A) bind to the enzyme at the active site. B) can decrease the energy of activation. C) can activate an enzyme. D) bind to an enzyme at a site different than the active site.
D
Students taking Bio 173, are studying an enzyme catalyzed reaction where the enzyme polyphenoloxidase binds to the substrate catechol and catalyzes the formation of the product ortho-quinone. If a competitive inhibitor "X" was added, which of the following is true? A) "X" binds to the regulatory site of polyphenoloxidase B) "X" binds to polyphenoloxidase by ionic interactions C) The Vmax of the reaction is lower in the presence of "X" D) Inhibition by "X" is decreased by increasing catechol concentration E) The Km of polyphenoloxidase is the same for catechol and "X"
D
What type of bond holds a T-A pair together in a DNA molecule? A) Glycosidic B) Peptide C) Phosphodiester D) Hydrogen
D
What type of interaction is responsible for the formation of secondary structure of proteins? A) Hydrogen bonds between R groups of amino acids B) Hydrogen bonds between two polypeptide chains C) Hydrogen bonds between adjacent amino acids D) Hydrogen bonds between portions of the polypeptide backbone
D
When coal is burned to produce electricity, the electrical energy produced is less than the potential energy of the coal. Which best explains this observation? A) As coal is heated, the molecules move so fast that they are destroyed B) Some of the energy in the coal is destroyed by the intense heat required to release its potential energy C) The amount of energy in the coal is not known D) Some of the potential energy in the coal is converted into forms of energy other than electricity
D
When cytosine makes a basepair, three hydrogen bonds are formed. When adenine makes a base pair, 2 hydrogen bonds are formed. In a DNA molecule that contains 8 total basepairs, three of which are guanine bases, how many total hydrogen bonds would be holding the 2 strands of DNA together? A) 16 B) 9 C) 24 D) 19 E) 0
D
Which of the following correctly matches an organelle with its function? A) Ribosome; lipid synthesis B) Lysosome; movement C) Nucleus; glycosylation D) Rough endoplasmic reticulum; protein synthesis E) Central vacuole; photosynthesis
D
Which of the following is NOT a function of the endomembrane system? A) Phagocytosis B) Digestion of damaged organelles C) Protein modification D) ATP production E) Protein export
D
Which of the following is composed of a 1:2:1 ratio of carbon:hydrogen:oxygen? A) Protein B) Enzyme C) DNA D) Carbohydrate
D
Which of the following is not a part of an amino acid? A) R group (or side chain) B) Alpha carbon C) Amino group D) Acetyl group
D
Which of the following is true of a catabolic (hydrolysis) reaction? A) Typically the reactants have a lower free energy than products B) It is endergonic C) It must be coupled to proceed D) It results in increased entropy E) It always involves an accompanying condensation reaction
D
Which of the following is true of a chemical reaction that splits a 6-carbon glucose molecule into two 3-carbon molecules (hydrolysis reaction)? A) the reaction results in decreased entropy B) the products in the reaction have the same free energy as the reactants C) the reactants are more stable than products D) the reaction is exergonic and therefore spontaneous E) the reaction is anabolic
D
Which of the following pairs incorrectly matches the structure to its function? A) Lysosome; autophagy B) Mitochondria; energy production c) Microtubules; cell motility D) Golgi apparatus; digestion and recycling
D
Which of the following reactions could be coupled to ATP hydrolysis to make it energetically favorable or spontaneous? ("to" is equivalent to an arrow) A) Glucose-1 phosphate + H2O to glucose + Pi ΔG= -5.0 B) Creatine phosphate + H20 to creatine + Pi ΔG = -3.0 C) Glucose + Pi to glucose-6 phosphate + H20 ΔG= +9.4 D) Glutamic acid + NH3 to glutamine ΔG=+3.
D
Which statement about a chemical reaction's transition state is false? A) The transition state is highly unstable. B) An input of energy is required for reactants to reach the transition state. C) During the transition state, chemical bonds are breaking and new ones are forming. D) Enzymes do not affect the energy required to reach the transition state.
D
Which statement about diffusion is false? A) Diffusion is an example of passive transport B) Diffusion results in a net movement of molecules from high to low concentrations. C) Diffusion does not require an input of energy. D) All types of molecules are able to diffuse across the plasma membrane.
D
Which structure is the site of the synthesis of proteins that are exported from the cell? A) Free cytoplasmic ribosomes B) Lysosomes C) Mitochondria D) Rough ER E) Golgi vesicles
D
You discover a new species of bacteria whose genome contains 30% cytosine. How much adenine does it contain? A) 50% B) 40% C) 60% D) 20% E) 30%
D
Hydrogen bonds are formed in each of the following situations EXCEPT A) Between purines and pyrimidines in a DNA molecule B) In the formation of alpha helical secondary structure of a protein C) Between water and a polar R group of a protein D) Between cellulose fibers that make up plant cell walls E) Between hydrogen and oxygen atoms in a single water molecule
E
In the DNA sequence 5'—CGATCG—3' the phosphodiester bond between the adenine and thymine connects: A) The 3' end of the adenine to the 3' end of the thymine B) The 2' end of the adenine to the 5' end of the thymine C) The 5' end of the adenine to the 2' end of the thymine D) The 5' end of the adenine to the 3' end of the thymine E) The 3' end of the adenine to the 5' end of the thymine
E