Portage Learning CHEM 210 exams 1-8 and final exam

Portage Learning CHEM 210 exams 1-8 and final exam Question 1 3 / 3 pts True or False: According to the Module, a compound with a molecular mass of 1,000 g/mol is considered a macromolecule. True Correct! False Question 2 3 / 3 pts True or False: Biomolecules can have only two functional groups. True Correct! False Question 3 3 / 3 pts True or False: The following functional group is an alcohol. True Correct! False Question 4 3 / 3 pts True or False: In a eukaryotic cell, the organelles called peroxisomes serve the purpose of digesting macromolecules. True Correct! False Question 5 3 / 3 pts True or False: Carbon dioxide has a linear molecular shape AND has a bond angle of 109.5o. True Correct! False Question 6 3 / 3 pts Of the following, is not a property of carbon. forming covalent bonds triple bond formation Correct! possessing five valence electrons reacting to form long chains called polymers forming multiple bonds Question 7 3 / 3 pts Which of the following is an element not typically found in living organisms? N Correct! He H S O Question 8 3 / 3 pts is a functional group found in carbohydrates. Esters Thiols Carboxylic acids Correct! Alcohols Amines Question 9 3 / 3 pts The following functional group is an example of . Correct! Ketone Thiol Amide Benzene Aldehyde Question 10 0 / 3 pts A is a chemical formula that does NOT show the C-H and C-C bonds. You Answered Covalent formula Line bond formula Empirical formula Kekule’ structure Correct Answer Condensed formula Question 11 3 / 3 pts A collection of two or more macromolecules uniting is called a . Correct! Supramolecular complex Monomer Macromolecular structure Dimer Kekule’ complex Question 12 3 / 3 pts An organic compound with this structure, C=C, contains a functional group. Alkane Correct! Alkene Alkyne Alcohol Both b and d Question 13 3 / 3 pts Scientists refer to as the “super glue” of the chemistry. Correct! C Co Na N O Question 14 3 / 3 pts What molecule is most important for energy storage in cells? Creatine mitochondria DNA RNA Correct! ATP Question 15 3 / 3 pts What would be the approximate size of a human cell? a. 12 μ m b. 1 nm c. 15 nm d. 0.2 inch e. 15 cm Correct! a. b. c. d. e. Question 16 3 / 3 pts For propane, there carbon and hydrogen atoms. 5, 12 4, 10 Correct! 3, 8 3, 6 None of the above Question 17 3 / 3 pts For an organic compound, which structure is the most efficient to draw? Correct! Line bond Condensed Lewis structure Structural formula None of these Question 18 3 / 3 pts When writing an organic functional group, scientists often write an “R” as part of the structure. What does the R indicate? A string of carbon atoms Radon Routine carbon atom Correct! Rest of the molecule None of the above Question 19 3 / 3 pts According to the module, the study of NON-carbon compounds is referred . Organic chemistry Correct! Inorganic chemistry Biochemistry Environmental chemistry None of the above. Question 20 3 / 3 pts Which of the following is not a functional group discussed in this module? Alcohol Amine Ketone Aldehyde Correct! All of these were discussed. Question 21 3 / 3 pts Which number would be closest to the approximate number of ribosomes in an E. coli cell? A. 1 B. 25 C. 250 Correct! D. 25,000 E. Both c and d Question 22 0 / 3 pts Which of the following would most likely have a cell wall? Correct Answer Marigold flower cells Deer cells Heart cells Human red blood cells You Answered All of the above Question 23 0 / 3 pts Eukaryotes have molecules that provide protective structural. This network is called the . Cell wall You Answered Cytoplasm Cytosol Correct Answer Cytoskeleton Both Cell wall and Cytoskeleton Question 24 3 / 3 pts The molecule linked to the medical condition of gout is . Correct! Uric acid Luciferin Luciferase Glucose Glycine Question 25 3 / 3 pts About how many different elements are found in living organisms? 9 Correct! 30 50 68 92 Question 26 3 / 5 pts (Short response) Explain the common similarity in all prokaryotic and eukaryotic cells. Give a brief explanation of the similarity. Your Answer: The common similarity between prokaryotic and eukaryotic cells are they both contain cells, a cell membrane and ribosomes. The fundamental similarity is that each cell type has a plasma membrane that separates life from non-life. The plasma membrane acts as a barrier to most molecules but does have proteins that permit select molecules to cross via proteins (transporters). The plasma membrane permits the cell to have a different composition of molecules inside the cell than out and defines a space for life to occur. Develop the membrane response further, based on module material. Question 27 2.5 / 5 pts (Short response) Would scientists be more likely to find an element such as O in a biomolecule, or W? Explain which she would more likely find in biological molecule and give specific physical/chemical properties. Your Answer: Scientists would be more likely to find an element of O in a biomolecule because O is a bulk element while W is a trace element. O is found is most strcutures and functional groups. She would more likely find O. Smaller elements are preferred. In the case of O, it is found in water, so it would be highly concentrated. Smaller elements with smaller atomic shells are favored because they can form stable covalent bonds. Strong bonds form by significant overlap of atoms, such as carbon and hydrogen permitting them to share electrons. The bond that forms requires a substantial amount of energy to break, which allows the bonds to withstand insults, such as mechanical and thermal stresses. This bond strength is good news for living organisms. Stable bonds allow cells to form, hair to grow, and skin to protect against abrasion. Larger elements, such as W, tend to form ionic compounds–not covalent. Describe why O is using the size/overlap. Question 28 3.5 / 5 pts (Short response) What element is the basis for life? Describe at least two properties of this element that permit it to serve the basis for life. Your Answer: Carbon is the element that is the basis for life. Carbon has the ability to form stable covalent bonds and unique combinations. Carbon has its own branch organic chemistry. 1. Carbon can form strong covalent bonds with a variety of different elements. 2. Besides, carbon can form double and triple bonds with other carbon atoms and other elements (N and o). 3. Carbon can form long chains by forming numerous carbon-carbon bonds; we call these large molecules polymer. 4. Lastly, carbon can form cyclic structures, which are also called ring compounds. Give one more property of carbon. Question 29 4 / 5 pts (Short response) How does organic chemistry differ from inorganic chemistry? Your Answer: Organic chemistry is focues on the chemical and physical properties of carbon and inorganic chemistry focues on non organic compounds. Organic chemistry is the study of the carbon-based compounds. Inorganic chemistry is the study of all other elements, but carbon. There is no need to have separate sub-disciples for organic and inorganic chemistry, but for historical and organizational reasons the difference exists. Include the non-carbon elements in your defintion of inorganic. Question 30 0 / 5 pts (Short response) Biochemists study the communication within and among organisms. According to the module, what are two other aspects of living organisms that biochemists study? Your Answer: Bichemists study carbs and proteins in living organism along with chemistry and biology. Also luciferin i studies and luciferase. In the module, biochemists also study the structure and function of biomolecules and the chemical reactions of organisms. Be more specific here. This is related to the homework problems and module material. EXAM 2 Question 1 3 / 3 pts The pH of a solution of 0.0010 M NaOH is: 1 Correct! 11 [Kw=[H+][OH-] = 1.0 x 10-14; [H+][0.0010] = 1.0 x 10-14 [H+]=1.0 x 10-11; pH=-log[1.0 x 10-11;]=11] 8 0 14 Question 2 3 / 3 pts Water is a unique molecule. Which of the following contributes to water’s unique place in the chemical world? The geometry of the molecule The polarity of the O-H bonds The ability of water molecules to hydrogen bond The bond angle of water Correct! All of the answers are correct Question 3 0 / 3 pts The bent shape of water is due to . The dipole arrows in a water molecule The electronegativity difference between hydrogen and oxygen You Answered The unequal electron sharing between hydrogen and oxygen Correct Answer The unshared electron pairs on the oxygen atom None of the answers are correct Question 4 0 / 3 pts Which diagrams correctly represent a hydrogen bond? Correct Answer A and D A and C You Answered B and C C and D B and D Question 5 0 / 3 pts The H+ concentration of a solution is 1.2 x 10-3 M. What is the pH? -1.20 1.20 You Answered 3.12 -2.92 Correct Answer 2.92 Question 6 3 / 3 pts If the Ka of an acid is 5.63 x 10-3, what is the pKa? 6.86 Correct! 2.25 [pKa = -log(5.63 x 10-3) = 2.25] 5.63 10.12 1.38 Question 7 3 / 3 pts List the acids in DECREASING order of strength (strongest to weakest): Nitrous acid (Ka = 4.0 x 10-4); acetic acid (Ka = 1.7 x 10-5); phosphoric acid (Ka = 7.3 x 10-3) Nitrous acid, acetic acid, phosphoric acid Acetic acid, nitrous acid, phosphoric acid Correct! Phosphoric acid, nitrous acid, acetic acid Acetic acid, phosphoric acid, nitrous acid None of the above Question 8 0 / 3 pts Elemental iodine (I2) is a solid at room temperature. What is the dominant attractive force that exists between I2 molecules in the solid? Correct Answer London forces Hydrogen bonds Halogen forces You Answered Dipole-dipole forces Covalent bonds Question 9 3 / 3 pts Which one of the following molecules can form a hydrogen bond? A. HBr B. HCl C. NH3 D. CH4 E. H2 A. B. Correct! C. D. E. Question 10 3 / 3 pts A hydrogen bond can form between a hydrogen atom bonded to oxygen, O–H, and . C B Cl P Correct! N Question 11 3 / 3 pts In a bond between P and Cl, there exists a difference in electronegativity resulting in partial positive and partial negative charges. If a dipole arrow where added to this structure, which way would the arrow point? The arrow points from Br toward N Correct! The arrow points from N toward Br Two arrows; one pointed in each direction There would not be a dipole arrow in this case. None of the above Question 12 3 / 3 pts The following reaction occurs in glues purchased from hardware stores. Customers use this product to glue plastic together. Epoxy (l) + hardener (l) ⟶ Glue (s) + heat given off What is the sign (+ or -) of the change in Δ G and Δ H? A) Δ G is (+) and Δ H is (-) B) Δ G is (-) and Δ H is (-) C) Δ G is (-) and Δ H is (+) D) Δ G is (+) and Δ H is (+) E) None of the above A Correct! B C D E Question 13 3 / 3 pts Which of the following is the free-energy change of a reaction? A) Δ G B) Δ S C) Δ H D) Δ F E) All of the above Correct! A B C D E Question 14 3 / 3 pts Which of the following is the change in entropy of a reaction? A) Δ G B) Δ E C) Δ H D) Δ F E) None of the above A B C D Correct! E Question 15 3 / 3 pts Correct! A B C D E Question 16 3 / 3 pts Which buffer system is used by the renal system to maintain pH balance? Phosphate buffer system Acetic acid buffer system Water buffers system Formic acid buffer system Correct! Bicarbonate buffer system Question 17 3 / 3 pts A buffer can neutralize acid and base within a certain limit. We say that this is its: Buffer limit Correct! Buffer capacity Buffer range Buffer maintenance Buffer arena Question 18 3 / 3 pts Is a pH of 8.36 acidic, neutral, or basic? Acidic Neutral Correct! Basic Both Acidic and Basic Both Neutral and Basic Question 19 3 / 3 pts The “ion product” is equal to what value? A. 1.0 x 10-4 B. 1.0 x 10-14 C. 2.1 x 10-7 D. 5.6 X 10-13 E. None of the above A Correct! B C D E Question 20 3 / 3 pts In equilibrium constant expressions, the concentration is expressed in units of as indicated the by the brackets [ ]. Correct! molarity acid value base value neutral value None of the above Question 21 3 / 3 pts A pH = 5.0 indicates a concentration of OH- (in M) of . A. 5 B. 10-5 C. 10-9 D. 10-1 E. 101 A B Correct! C D E Question 22 3 / 3 pts The lysosome has a pH of 5.0. Which of the following weak acids would best work to buffer at pH 5.0? Formic Acid Dihydrogen phosphate Correct! Propionic acid Tartaric acid All of these Question 23 3 / 3 pts Which of the following compounds would not be soluble in water? A. NaCl B. OH- C. Glucose D. Wax E. All of the above would be soluble A B C Correct! D E Question 24 3 / 3 pts The oxygen in water has what type of hybridization? A. sp B. sp2 C. sp3 D. sp3d E. All of the above A B Correct! C D E Question 25 3 / 3 pts Four identical molecules dissolve in water. Each molecule contains both a polar portion and nonpolar portion of structure. The four molecules interact in such a way that the nonpolar sections align. This is an example of the . Buffering capacity Hydrophilic effect Hydrogen bonding effect Correct! Hydrophobic effect All of the above Question 26 5 / 5 pts (Short Response) How does the strength of a hydrogen bond compare to the strength the London Force? Also, how about the strength of a hydrogen bond compare to a dipole-dipole force? Briefly comment on these differences. Your Answer: The hydrogen bond is the strongest non-covalent force while london forces are the weakest. The dipole-dipole forces are the 2nd strongest forces. 1) hydrogen bonding 2) dipole-dipole forces 3) London forces The hydrogen bond strength is between 12 and 16 kcal, while the London force is generally less than 1 Kcal. A dipole-dipole bond usually is from 0.5 to 2.0 kcal. Also, hydrogen bonds are the strongest non-covalent force, which is illustrated by these numbers. Question 27 5 / 5 pts Your Answer: Ka= {H+][X-] / HX = 0.55M x 0.55M / 0.64M Ka= .4727 M Question 28 0 / 5 pts Your Answer: H+ in the solution must be decreasing while OH- increases. With the additon of the acid, the water value od 1.0 x 10-14 stays constant. Show any change using the equation. Question 29 2 / 5 pts (Fill in the blanks) At cool temperatures, water vapor turns into liquid water releasing heat in the process. Fill in the missing blanks, below, regarding this process. Please identify your answers by writing “A.” then your answer, “B” then your answer, and so forth. The free-energy change, Δ G, has a A value (choose “+” or “-“). The enthalpy change, B (fill in symbol), has a C value (choose “+” or “-“). The D change, ( Δ S) has a E value (choose “+” or “-“). Your Answer: A: - B: - C: - D: + E: + A) “-“ B) L a T e X : Δ L a T e X : Δ H C) “-“ D) entropy E) “-” "A" and "C" are correct. Question 30 2.5 / 5 pts (Short Response) What is the hydrophobic effect and how does a clathrate help explain this phenomenon? Your Answer: Te hydrophobic effect is nonpolar substances to aggregate in an aqueous solution and exclude water molecules. Water prefers to interact with itself. Water pushes things together and forms a plasma membrance. Clathrate forms a tight structure. The hydrophobic effect helps scientists explain how biological molecules form and interact. For instance, when molecules with both a nonpolar and polar regions dissolve in water, the nonpolar regions pack together. The packing of the nonpolar regions minimizes the interaction with water and the polar region interact with water, which in total is called the hydrophobic effect. The driving force behind this effect is the spontaneous drive of water to bind to itself through hydrogen bonds. To maximize the hydrogen bonds, water orders itself around the hydrophobic portion of the nonpolar regions in a cage structure also called a clathrate. In so doing, water can form bonds with itself and also permit the nonpolar regions to be dissolved. Include a little more detail. EXAM 3 Question 1 3 / 3 pts True or False: The amino acids serine and methionine both contain sulfur atoms. True Correct! False Question 2 3 / 3 pts True or False: The following secondary structure shown below is an example of a beta-turn. True Correct! False Question 3 3 / 3 pts True or False. The side chain of proline is bonded to the backbone nitrogen atom. Correct! True False Question 4 3 / 3 pts True or False: The name of the molecule that binds to an enzyme is called the apoenzyme. True Correct! False Question 5 3 / 3 pts True or False: An inhibitor that binds at the active site is an uncompetitive inhibitor. True Correct! False Question 6 3 / 3 pts Which amino acids differ by only one atom? Ser and Thr Leu and Ile Ala and Ser Asp and Asn Correct! Ser and Cys Question 7 3 / 3 pts The formation of a peptide bond between two amino acids is an example of a(n) reaction. Cleavage Correct! Condensation Group transfer Isomerization Double-bond breaking Question 8 3 / 3 pts The peptide Ala-Glu-Gly-Ala-Leu-Arg has . A disulfide bond Correct! Five peptide bonds Four peptide bonds A proline residue No C-terminal Question 9 3 / 3 pts Formally, when there are 99 or more amino acids are covalently linked together that is called a . Polypeptide Oligopeptide Peptide Correct! Protein Polyprotein Question 10 3 / 3 pts What unit is used by biochemists to indicate the mass of a protein? g/mol Correct! Da Ba Mol/g g Question 11 3 / 3 pts All of the 20 standard amino acids contain an R-group that is attached to the: A) α carbon B) Carboxyl group C) Amino group D) β carbon E) None of the above Correct! A B C D E Question 12 3 / 3 pts Which of the following correctly matches the amino acid with its one letter abbreviation? Tyrosine, T Lysine, L Phenylalanine, P Correct! Aspartic acid, D Proline, R Question 13 3 / 3 pts By convention, polypeptides are read in which order? Correct! N to C-terminus C to N-terminus 5’ to 3’ 3’ to 5’ Smallest to largest amino acid by weight Question 14 3 / 3 pts Roughly how many amino acids are there in one turn of an alpha helix? 1 2.8 Correct! 3.6 4.2 10 Question 15 0 / 3 pts In an alpha helix, the R groups on the amino acid residues: Alternate between the outside and inside of the helix Correct Answer Are found on the outside of the helix spiral You Answered Cause only right-handed helices to form Generate the hydrogen bonds that form the helix Stack within the interior of the helix Question 16 0 / 3 pts Motifs are classified primarily by their: Amino acid sequence Evolutionary relationships You Answered Function Correct Answer Secondary structure content and arrangement Subunit content and arrangement Question 17 3 / 3 pts The secondary structure shown below is an example of a(n): Correct! Parallel beta sheet Antiparallel beta sheet alpha helix beta-turn alpha-turn Question 18 3 / 3 pts A single folded polypeptide has a globular shape, which describes its structure. Secondary Correct! Tertiary Quaternary Quasi Motif Question 19 3 / 3 pts How many classes of enzymes are recognized by the IUBMB? 3 4 5 Correct! 6 7 Question 20 0 / 3 pts An enzyme requires Cr+3 for catalysis. When the enzyme contains the Cr3+ it called a/an . Correct Answer Holoenzyme Apoenzyme You Answered Fully ready molecule Inhibitor Competitive inhibitor Question 21 3 / 3 pts When a substrate has just started its conversion to a new molecule, it is said to be in the . Stable mode Unstable mode Correct! Transition state Conversion State Conversion Mode Question 22 3 / 3 pts Which of the following would change the rate of an enzyme-catalyzed reaction? amino acids, concentration, and temperature Correct! pH, concentration, and temperature pH, polarity, and concentration polarity, concentration, and temperature pH, polarity, and temperature Question 23 3 / 3 pts The concept of induced fit refers to the fact that: When a substrate binds to an enzyme, the enzyme induces loss of water Enzyme specificity is induced in the enzyme-substrate The enzyme-substrate binding increases the temperature Correct! Substrate binding induces a conformation change in the enzyme The substrate bends and twists before it binds to the enzyme Question 24 3 / 3 pts The ES stands for: Correct! Enzyme-substrate Energy-substance Enzyme-specificity Energy-specificity None of the above Question 25 3 / 3 pts Any molecule or ion that is necessary for an enzyme’s function is called a: Correct! Cofactor Coreactant Coproduct Bienzyme Both B and C Question 26 5 / 5 pts (short response) A) Is the following protein globular or fibrous? Explain. B) Identify the types of secondary structure present in the following protein. Your Answer: This is a globular protein because the proteins are folded into conformations. The types of secondary structures present include are alpha helices of ribbon diagram and parallel beta turn strands. A) It is a globular protein because of its ball-like shape. Fibrous proteins are usually long and extended. B) There is one alpha helix in front and some in the back. Also present is a beta sheet; there seems to be both parallel and antiparallel strands here. It is ok if the student does not mention beta turns; those are harder to pick out (may not be any here). Question 27 5 / 5 pts (short response) Staphylokinase is said to be a dimer. A) What is a dimer? B) Structurally, a dimer describes what level of protein organization? Your Answer: A dimer contains two polypeptides with two subunits. A dimer describes a quaternary structure. A) This enzyme has two independent polypeptide chains interacting non-covalently. In this case, they are identical chains. B) It is describing the quaternary structure, which has two or more independent polypeptide chains that associate with one another to form a quaternary structure. Question 28 5 / 5 pts (short response) There are collections of protein structure that fit between true secondary and true tertiary structure. What is the name of the collections of protein structure? Explain this type of structure. Your Answer: These collections of protein structure are super secondary structures. This type of structure contains a motif a beta meandor. This occurs before the protein forms into its 3 dimensional tertiary structure. Motifs occupy a position between secondary and tertiary. Motifs are particularly stable arrangements of secondary structure, including the connections between them. Motifs are found in a variety of proteins from across all organisms. Question 29 5 / 5 pts (Short response) A. What is the lowest level of protein structure? And B) How do scientists communicate information about this level? Your Answer: The lowest level of protein structure is the primary structure. Scientists communicate information using one letter abbrevations to show the amino acid sequence. The N-terminal amino acid residue is started on the left and continue to the right in the direction of the C- terminal. This is used to determine polar and non polar stretches in the protein. The primary level is the order of amino acids covalently bonded together, including disulfide bonds, in a polypeptide chain. The primary sequence is written, for proteins, from N to C terminal using the one-letter or three-letter abbreviations. Question 30 5 / 5 pts What is the spot on an enzyme where reactions take place? Explain the characteristics of this spot. Your Answer: Active spots are places on an enzyme where a reaction takes place. This is referred to as catalysis. This is small compared to the overall size of the molecule. Most have about 10 amino acids residues in this space. These spots procide energy to initate the reaction. The active site is the spot on the enzyme where catalysis takes place. This area is often small when compared to the overall size of the protein. In fact, about 10 amino acids make up the active site. EXAM 4 Question 1 3 / 3 pts Which of the following monosaccharides is not an aldose? Erythrose Correct! Dihydroxyacetone Glucose Glyceraldehyde Ribose Question 2 3 / 3 pts When two monosaccharides are epimers: They differ only in the configuration about the penultimate carbon One is an aldose, the other a ketose Correct! They differ only in the configuration about one carbon atom They form O-glycosidic bonds They are oligosaccharides Question 3 3 / 3 pts Which pair is anomeric? A) D-glucose and D-fructose B) D-glucose and L-fructose C) D-glucose and L-glucose D) α -D-glucose and β -D-glucose E) α -D-glucose and β -L-glucose A B C Correct! D E Question 4 3 / 3 pts Lactose is made from linking galactose and glucose. When this happens, . A polysaccharide is formed Gas is eliminated An epimer is formed An anomeric carbon is formed on carbon-1 Correct! Lactose forms by a condensation reaction Question 5 3 / 3 pts Chitin and cellulose are both polymers of: A) α -D-glucose B) Galactose C) β -D-glucose D) Idose E) Maltose A B Correct! C D E Question 6 3 / 3 pts Which statement about starch and glycogen is false? A) Amylose is unbranched; amylopectin and glycogen contain many ( α 1 → 6) branches B) Both are heteropolymers of glucose C) Both have many -OH groups in their structures D) Both starch and glycogen are energy storage polysaccharides E) Glycogen is more extensively branched than starch A Correct! B C D E Question 7 3 / 3 pts Which monosaccharide is not a six-carbon monosaccharide? Idose Gulose Galactose Correct! Dihydroxyacetone Allose Question 8 0 / 3 pts The two monosaccharides shown below could best be described as: You Answered Anomers Ketoses Correct Answer Aldoses Rotamers Pentoses Question 9 3 / 3 pts Which arrow correctly identifies the atom that will become the anomeric carbon? Correct! A B C D E Question 10 0 / 3 pts Based on the form of the cyclic sugar below in a Haworth projection, which Fischer projection formula could have formed this structure? A B C Correct Answer D You Answered E Question 11 3 / 3 pts The following monosaccharides are covalently bonded. What type of bond unites them? A) α 1 → 4 B) α 1 → β 4 C) 1, 4 D) α 1 → 6 E) β 1 → 6 A B C Correct! D E Question 12 3 / 3 pts Which statement about cellulose is true? Correct! Cellulose is found in plants Cellulose is the primary storage polysaccharide of animal cells Cellulose is found in DNA The glucose residues of cellulose contain the same configuration as the glucose residues of amylose Cellulose is an epimer of chitin Question 13 3 / 3 pts The polysaccharide cellulose is most chemically similar to: Glycogen Dextrose Glycogen Correct! Chitin Starch Question 14 3 / 3 pts Which of the following is most common monosaccharide on earth? Ribose Cellulose Chitin Sucrose Correct! Glucose Question 15 3 / 3 pts The “D” in the D-carbohydrates stands for: 3-dimensional Correct! Dextrorotatory Derivative Design Double Question 16 3 / 3 pts Which compound does not fit the formal definition of a carbohydrate? A. C6H12O6 B. C7H10O7 C. C8H16O8 D. C3H6O3 E. C4H8O4 A Correct! B C D E Question 17 3 / 3 pts Which letter represents the hemiacetal bond? A B Correct! C D E Question 18 3 / 3 pts What is the configuration of the following compound? A) α B) β C) D D) L E) Both A and C A B C Correct! D E Question 19 3 / 3 pts Sucrose is also known as: Lactose Milk sugar Chitin Correct! Table sugar Glycogen Question 20 3 / 3 pts Amylopectin has α 1 → 6 branching about residues. 1 to 10 8 to 12 10 to 30 Correct! 24 to 30 No branching Question 21 3 / 3 pts Besides C, H, and O, chitin has which other element in its structure? F Cl P S Correct! N Question 22 3 / 3 pts Amylose folds into which of the following structures? A) β eta-sheet B) β -turn C) α -helix D) D-configuration E) α form A B Correct! C D E Question 23 3 / 3 pts The equilibrium between structures is called mutarotation. A) Anomer and epimer B) α and β C) L and D D) Helix and beta sheet E) None of the above A Correct! B C D E Question 24 3 / 3 pts Consider the functions of carbohydrates. Which of the following is not a function of these molecules? Structure Energy storage Correct! Enzyme structure Both A and B Both A and C Question 25 3 / 3 pts The word saccharide means . Correct! Sugar Carbohydrate Energy molecule Sucrose Starch Question 26 5 / 5 pts (Short response) The following oligosaccharide interacts favorably with water. What is the source of the ability of the interaction between H2O and this carbohydrate? Your Answer: The OH groups on the oligosaccharide forms hydrogen bonds with water molecules. This forms an aqueous solution. This does not allow the carbohydrate to become more soluble to water. Oxygen is the source of the connections between these chains. The –OH groups on the oligosaccharide form many hydrogen bonds with water molecules. For this reason, the carbohydrate forms an aqueous solution with many molecules dissolving. These interactions permit water to solubilize the carbohydrate. Question 27 5 / 5 pts (Short response) In the following structure: A) How many monosaccharide units are furanoses and how many are pyranoses? B) What is the linkage between the monosaccharides? C) Is this a reducing sugar? Your Answer: A) 2 pyranoses and 0 furanoses B) β 1 ⟶ 4 C) yes, a free anomeric carbon is present. A) 2 pyranoses; 0 furanoses B) L a T e X : β 1 L a T e X :→ 4 C) yes, it has free anomeric carbon Question 28 5 / 5 pts (Short response) Explain in molecular terms why humans cannot use cellulose as a nutrient. Your Answer: The human enzyme is unable to break down the bond that associates with cellulose. The bond with cellulose is a β 1 ⟶ 4 linkage. Humans can split only α 1 ⟶ 4 linkages. Since the human body is unable to break down cellulose, it is not able to be used as a nutrient. The human enzyme cannot break down the bond between the sugar residues. The bond is a L a T e X : β 1 L a T e X :→ 4, but human enzymes only act upon L a T e X : α 1 L a T e X :→ 4. Question 29 5 / 5 pts (Short response) How are oligosaccharides and polysaccharide similar in their structure? How are they different? Your Answer: Polysaccharides differ from oligosaccharides in the sense that they're complex carbohydrates. They are polymers made up of many monosaccharides. They are very large, branched macromolecules. They're insoluble in water. Oligosaccharides are much smaller and only contain 3-10 monosaccharides. They are soluble in water and are very large branched and unbranched polymers. They're both similar that they both contain monosaccharides. An oligosaccharide is a polymer of 2 to 20 monosaccharides joined together. A polysaccharide is more than 20 monosaccharides joined together. They are typically linked together by the same 1 L a T e X :→ 4 linkages practically, and there are usually thousands of monosaccharides in a polysaccharide. In addition, polysaccharides can have branches in the structure, which permits them to form large complexes. In contrast, most oligosaccharides do not have branching. Question 30 5 / 5 pts (Short response) A) Which carbon in the following molecule determines if the molecule is D or L? Explain. B) Is this molecule D or L? Your Answer: Carbon D. It is the penultimate carbon. The monosaccharide is L because the HO is on the left side. Carbon D. It is the penultimate carbon and tells the viewer if the sugar is D or L. This EXAM 5 Question 1 3 / 3 pts Glycerol contains how many carbon atoms? Correct! 3 4 5 15 None of the above Question 2 3 / 3 pts Which of the following are derived from or made from fatty acids? Cholesterol Carotenoids Correct! Phosphoglycerides Both A and B Both A and C Question 3 3 / 3 pts Triacylglycerols are made from a and . glycerol; cholesterol Correct! glycerol; three fatty acids ceramide; three fatty acids ceramide; three cholesterols carotenoid; two cholesterols Question 4 3 / 3 pts A B Correct! C D E Question 5 0 / 3 pts A is a carboxylic acid that is a structural component of lipids. Amino acid Carotenoid You Answered Sphingolipid cholesterol Correct Answer None of the above Question 6 3 / 3 pts A particular lipid is a liquid at room temperature, so it is called a(n) . Correct! Oil Fat Lipid Membrane Sphingolipid Question 7 3 / 3 pts Identify the lipid class given by the structural formula: Phosphoglyceride Correct! Sphingolipid Cholesterol Triacylglycerol None of these Question 8 3 / 3 pts are a class of membrane proteins that are loosely associated with the membrane bilayer. Transmembrane protein Integral protein Channel protein Transport protein Correct! Peripheral protein Question 9 0 / 3 pts Isoprene units are used to make all of the following except . Correct Answer A. Fatty acids B. Carotenoid molecules C. Sphingolipids D. Both B and C You Answered E. All of the above Question 10 3 / 3 pts Which notation is for a fatty acid with one double bond? A) 18:1( Δ 12) B) 1:18( Δ 12,15) C) 1:12( Δ 12) D) 2:18( Δ 12,15) E) 12:1( Δ 7,9) Correct! A B C D E Question 11 0 / 3 pts Which notation indicates a 14-carbon omega-3 fatty acid that contains no other double bonds? A) 14:1 ( Δ 11) B) 17:1( Δ 14) C) 14:1( Δ 3) D) 13:1( Δ 11) E) 14:0( Δ 11) Correct Answer A B C D You Answered E Question 12 3 / 3 pts is used as the backbone molecule in the formation of storage fats. Ceramide Glucose Sphingolipid Correct! Glycerol Phosphoglycerol Question 13 3 / 3 pts molecules determine blood type in humans. Correct! Sphingolipids Triacylglycerols Cholesterol Phosphoglycerides carotenoid Question 14 3 / 3 pts are found in high concentrations in the membranes of the myelin sheath. Fatty acids Cholesterol Triacylglycerols Correct! Sphingolipids Vitamin K molecules Question 15 3 / 3 pts In a sphingolipid, the fatty acids are attached at carbon-2 by this type of linkage? Correct! Amide linkage An ether linkage An alcohol linkage A peptide linkage Alkyl linkage Question 16 3 / 3 pts Membrane proteins: Are sometimes peripheral Are sometimes integral Are types of lipids Correct! Both A and B None of the above Question 17 3 / 3 pts Peripheral membrane proteins Go all the way through the membrane Correct! Can be chemically separated from the membrane Are firmly attached to the membrane Are lipids None of the above Question 18 0 / 3 pts Which statement best describes a general feature of membranes? The membrane breaks easily Individual lipid molecules stay in one place The polar heads face inward You Answered The interior of the lipid bilayer is very polar Correct Answer The membrane is fluid Question 19 3 / 3 pts The following cartoon drawing represents which lipid type? Sphingolipid Triacylglycerol Correct! Phosphoglyceride Cholesterol None of these Question 20 3 / 3 pts Which vitamin is critical for blood coagulation? Vitamin A Vitamin B Vitamin C Vitamin D Correct! Vitamin K Question 21 0 / 3 pts What molecule is not found in membrane bilayers? Phosphoglycerides Sphingolipid Cholesterol You Answered Integral proteins Correct Answer None of these Question 22 3 / 3 pts What molecule that protects against UV rays is found both in bacteria and in the eyes? Phosphoglycerides Triacylglycerol Cholesterol Correct! Carotenoid Vitamin K Question 23 3 / 3 pts What molecule has four fused rings in its structure? Sphingolipid Carotenoid Triacylglycerol Correct! Cholesterol Water Question 24 3 / 3 pts In triacylglycerols, fatty acids are attached to glycerol via linkage. Correct! -O-CO- -NH- -O-NH- -COO- -C=C- Question 25 3 / 3 pts A lipid is . A fat An oil Correct! A molecule that dissolves in a non-polar solvent Is made from isoprene units Is water soluble Question 26 5 / 5 pts (Short answer) What is the effect of a double bond on structure of fatty acids? Your Answer: This is referred to as unsaturated fatty acids. A double bond reduces the flexibility of a fatty acid chain. It also reduces the chain length and keeps the chain straight. Double bonds are important because they regulate the temperature. Most double bonds cause the fatty acids to bend or kink about in solution. This bending reduces the packing structure of fatty acids making them more liquid-like. Question 27 4 / 5 pts (short answer) Where in the body are membranes found? Your Answer: Membranes can be found all over the body. They can cover the body, line body cavities, and cover organs. In the cell. The cell, itself, and the organelles have membranes. Connect to cell membranes specifically. Question 28 5 / 5 pts (short answer) What type of lipid contains a ceramide? What is the purpose of this lipid? Your Answer: Sphingolipids contains a ceramide. The purpose of this lipid is to form the structure of membrane bilayers and in the myelin sheath of neurons. They also aid in defining blood type in individuals. Sphingolipids. Sphingolipids are structural lipids that form membrane bilayers with specific functions. Sphingomyelins are a subtype of sphingolipids that occur in all membrane bilayers but are especially prominent in the myelin sheath of some neurons. This subclass of sphingolipids typically has a polar head group with a neutral charge. Another vital function of sphingolipids is that they define the blood type of individuals. Question 29 5 / 5 pts (short answer) What is the most significant chemical difference between triacylglycerols and phosphoglycerides that lead to their different functions? Your Answer: Phosphoglycerides have two fatty acid attached to the glycerol. Triacylglycerols have three fatty acids. Phospoglycerides also have a polar head group attached. Triacylglycerols are nonpolar molecules that can be stored as energy. Phosphoglycerides have both polar and nonpolar regions that permit them to interact with both polar and nonpolar environments making them perfect for membrane bilayers. Question 30 5 / 5 pts (short answer) What is the fluid mosaic model and what feature of the cells does it help us understand? Your Answer: The fluid mosaic model is a mixture of lipids and proteins that form the membrane bilayer. This helps to maintain life inside the cell. The features of cells it helps us undestand include lipid molecules with polar head groups, a bilayer, eahc layer has a unique composition, dynamic movement of molecules and non-covalent interactions. Helps us explain membrane compositiion. The fluid mosaic model helps us understand biological membranes. It describes the fluid, complex nature of the membrane bilayer. Membranes have lipids and proteins in a rich mixture to help the cell survive. EXAM 6 Question 1 3 / 3 pts In DNA, adenine always pairs with . Correct! Thymine Guanine Uracil Cytosine Both A and B Question 2 3 / 3 pts DNA is built from which of the following? Nucleosides Genes Purines Correct! Nucleotide Codons Question 3 3 / 3 pts The double helix of DNA is stabilized mainly by . Ionic bonds Covalent bonds Ion-dipole bonds Correct! Hydrogen bonds Hydrogen covalent bonds Question 4 3 / 3 pts Which of the following pentose sugars is a constituent of DNA? Xylose Ribitol Correct! 2-deoxyribose Arabinose Ribose Question 5 3 / 3 pts Pyrimidines have ring(s), (each) containing nitrogen(s), whereas purines have ring(s), (each) containing nitrogen(s). 1; 1; 1; 1 Correct! 1; 2; 2; 2 2; 2; 1; 2 2; 1; 1; 2 2; 2; 1; 1 Question 6 3 / 3 pts Identify the base guanine from among the following structures. A. B. C. D. E. A B C Correct! D E Question 7 0 / 3 pts Which of the following nucleic acids is responsible for using the encoded genetic information to produce of proteins found in living organisms? Peptide nucleic acid Correct Answer Ribonucleic acid Ribitol nucleic acid You Answered Deoxyribonucleic acid Glycerol nucleic acid Question 8 3 / 3 pts Identify the complementary bases from the following. Adenine-Cytosine Correct! Adenine- Thymine Guanine-Thymine Guanine-Adenine Cytosine-Uracil Question 9 3 / 3 pts How many hydrogen bonds are made between G and its complementary nucleotide? 1 2 Correct! 3 4 5 Question 10 3 / 3 pts The base sequence along one strand of DNA of 5’-GCATGAGCC-3’. What is the sequence of the complementary strand of DNA? 5’-CTAGTCCGC-3’ Correct! 3’-CGTACTCGG-5’ 3’-CTAGTCCGC-5’ 3’-CAGTCAGCT-5’ 5’-CTGACTACG-3’ Question 11 3 / 3 pts Which of the following types of RNA functions to carry genetic information from the DNA to ribosome? Correct! mRNA gRNA rRNA snRNA tRNA Question 12 3 / 3 pts Which of the following is the set of three sequential nucleotides that encodes for a particular amino acid? Correct! Codon Anticodon Allele Gene Chromosome Question 13 3 / 3 pts A type of DNA that has a right-handed helix is the . t-form X-Form Correct! B-form L-form Z-form Question 14 3 / 3 pts Which of the following is a second messenger in cells? FAD Correct! cAMP AMP dATP UTP Question 15 3 / 3 pts Which of the following acts a coenzyme? Correct! FAD ATP AMP cAMP GGG Question 16 3 / 3 pts rRNA makes up about percent of ribosomes. 35 Correct! 65 20 90 15 Question 17 0 / 3 pts The conclusion that G and C are present in DNA in equimolar is credited to . James Watson Francis Crick Correct Answer Erwin Chargaff You Answered Both A and B None of the above Question 18 0 / 3 pts The order of nucleotides in DNA is written . to C C to N 3’ to 5’ Correct Answer 5’ to 3’ You Answered Both C and D Question 19 3 / 3 pts In the Watson-Crick model for the double helix, which statement is NOT true? The two strands run anti-parallel to one another The base-pairing occurs on the inside of the double helix. The double helix (B form) is right-handed. Correct! Two equally sized grooves that run up the sides of the helix. The two strands have complementary sequences. Question 20 3 / 3 pts In the tRNA, below, the amino acid is attached to which position? Correct! A B C D E Question 21 3 / 3 pts Besides ATP, which other nucleotide is part of energy storage in cells? ATP UTP TTP CTP Correct! GTP Question 22 0 / 3 pts Which of the following is a nucleoside? A. B. C. D. E. Both A and C A B You Answered C D Correct Answer E Question 23 3 / 3 pts Which of the following is heterocyclic? A. B. C. D. Both B and C E. None of the above A B Correct! C D E Question 24 3 / 3 pts A major component of RNA but not DNA is: AMP GMP Correct! UMP CMP TMP Question 25 3 / 3 pts On the following molecule, which letter (A, B, C, D, or E) indicates the 5’ end? Correct! A B C D E Question 26 5 / 5 pts (Short answer) Scientists say that two DNA strands are complementary. Briefly describe what is meant by complementary Show one example in your response. Your Answer: What is meant by two DNA strands being complementary essentially is that every base hair a pair, G and C will always be a pair as well as T and A. There can never for example, G and T can never be a pair. They are represented in an anti-parallel direction as shown below. There are 11 nucleotides in each strand. 5'-GCCTTAGCAAT-3' 3'-CGGAATCGTTA-5' The nucleotide sequences of complementary strands are such that, whenever an A occurs in one strand, there is a T in the other strand with which it can form a hydrogen-bonded base pair. Whenever a C occurs in one strand, a G occurs in the other. A is the base that is complementary to T, and C is the base complementary to G. Question 27 5 / 5 pts (Short answer) Briefly describe how noncovalent interactions contribute to the three-dimensional shapes and structures of RNA molecules. Your Answer: RNA contains G,C and U. Sugar and phosphate are linked together. Sugar and N base are linked together. Two N bases are linked together by hydrogen bonding. Hydrogen bonding in regions of complementarity within an RNA chain can result in the formation of a structure. If no complementary regions exist then an unstructured area will exist within the RNA. Question 28 5 / 5 pts (Short answer) In one sentence, identify the most noticeable difference between the A-form of DNA and the Z form of DNA. Your Answer: The Z-form of DNA is left handed while the A-form of DNA is right handed. A-form is a right-handed helix while the Z-form of DNA is a left-handed helix. Question 29 5 / 5 pts (Fill in the blanks) In nucleic acid chemistry, compounds that contain an organic nitrogen-containing base, a sugar, and phosphate group are called A . Two purines found in DNA in are B and B . A pyrimidine found in all RNA but not in DNA is C . In DNA, the pair D is held together by three hydrogen bonds. In DNA, the pentose E serves as the monosaccharides. Your Answer: A) nucelotides B) Adenine and Guanine C) Uracil D) G and C E) deoxyribose A) Nucleotides B) adenine and guanine C) Uracil D) G-C E) 2-deoxyribose Question 30 5 / 5 pts (Short answer) The monomers of RNA nucleic acids, called nucleotides, consist of three parts. What are those three parts? (Give three) Your Answer: 1) A base 2) Monosaccharide 3) phosphoric acid phosphoric acid, ribose (a pentose sugar) and an organic base. EXAM 7 Question 1 3 / 3 pts True or False: The Δ G value for a particular reaction is -78kJ/mol. This value indicates the reaction is spontaneous. Correct! True False Question 2 3 / 3 pts True or false: A biochemical metabolic pathway is a single reaction that converts starting material into products. True Correct! False Question 3 3 / 3 pts True or false: Three ATP molecules are used in the energy-investing stage of glycolysis. True Correct! False Question 4 0 / 3 pts True or False: The citric acid cycle occurs in the presence of oxygen. Correct Answer True You Answered False Question 5 0 / 3 pts True or false: The β -oxidation pathway only degrades odd-numbered fatty acids. Correct Answer True You Answered False Question 6 3 / 3 pts In total, how many ATP or NADH are produced (or required) in the glucose to pyruvate steps in glycolysis? 1 NADH required 1 ATP and 2 NADH required Correct! 2 ATP and 2 NADH produced 2 ATP produced None of the above Question 7 3 / 3 pts In converting glucose to pyruvate, how many ATP or NADH are produced (or required) in the fructose-6-phosphate to fructose-1,6-phosphate step in glycolysis? Correct! 1 ATP required 1 ATP produced 2 ATP produced 2 ATP required None of the above Question 8 3 / 3 pts What is the primary product of glycolysis? Glucose Glucose-6-phosphate phosphoenolpyruvate GAP and DHAP Correct! Pyruvate Question 9 3 / 3 pts In glycolysis, when glucose enters a cell, it is immediately phosphorylated to form glucose-6- phosphate. The phosphate donor in this reaction is ATP, and the enzyme is . Correct! Hexokinase Aldolase CoA Phosphohexose isomerase None of the above Question 10 3 / 3 pts In the last reaction of glycolysis, ATP is formed by the direct transfer of a phosphate group from a metabolite to ADP. This process is referred to as: Correct! Substrate-level phosphorylation Protein phosphorylation Lipid phosphorylation Isomerization Photo-protein dephosphorylation Question 11 3 / 3 pts Under anaerobic conditions, to which compound is pyruvate converted? Correct! Ethanol DHAP Hexokinase GAP None of the above Question 12 3 / 3 pts There are reactions in glycolysis. 6 8 9 Correct! 10 12 Question 13 3 / 3 pts The reactions of glycolysis take place in/on the . Mitochondria Vacuoles Ribosome Correct! Cytosol None of the above Question 14 3 / 3 pts How is ATP used in the initial steps of glycolysis? Lipid phosphorylation reagent Isomerization reaction Correct! Source for phosphorylation Protein production None of the above Question 15 3 / 3 pts Which of the following is a cyclic pathway? A. CAC B. PDH C. Glycolysis D. Oxidative phosphorylation E. β -oxidation Correct! A B C D E Question 16 3 / 3 pts How many ATP molecules does NADH yield after oxidative phosphorylation? 1.5 2 Correct! 2.5 3 3.5 Question 17 0 / 3 pts Besides NADH and FADH2, what energy molecule is produced directly in the citric acid cycle? A. CO2 B. ATP C. CTP D. UTP E. None of the above You Answered A B C D Correct Answer E Question 18 3 / 3 pts What molecule is missing in the following reaction? A. PDH B. Isocitrate C. Fumarate D. FADH2 E. Succinyl-CoA A Correct! B C D E Question 19 3 / 3 pts The enzymes and coenzymes of the citric acid cycle are all present in the . Correct! Mitochondria Vacuoles Nucleus Lysosomes None of the above Question 20 3 / 3 pts Cellular respiration is the process of cells taking in and producing to generate energy. A. Glucose; NADH B. FAD; FADH2 C. CO2; ATP D. NAD+; NADH E. O2; CO2 A B C D Correct! E Question 21 3 / 3 pts The complete degradation of glucose via cellular respiration occurs in phases. 1 2 Correct! 3 alternate reversible Question 22 3 / 3 pts What are the names of the three enzymes that convert pyruvate to acetyl-CoA A. P, D, and H B. Enzyme A, Enzyme B, and Enzyme C C. Enzyme a, Enzyme b, and Enzyme c D. E1, E2, and E3 E. None of the above A B C Correct! D E Question 23 3 / 3 pts Of the following, which coenzyme(s) are necessary for β -oxidation? A. O2 B. FAD C. GTP D. Both A and B E. None of the above A Correct! B C D E Question 24 3 / 3 pts Which of the following letters corresponds to the α -carbon of a fatty acid? A Correct! B C D E Question 25 3 / 3 pts The process for degrading fatty acids is commonly referred to as: A. β -degradation B. α -degradation C. Spiral D. β -spiral E. α -spiral A B C Correct! D E Question 26 2 / 5 pts (Short answer) In one step of the glycolysis pathway, a six-carbon compound is broken into two three-carbon fragments, only one of which can be further degraded in the glycolysis pathway. What happens to the other three-carbon fragment? Your Answer: In this phase, each 3 carbon suagr is converted into another 3 carbon molecule, pyruvate through a series of reactions. In these reactions 2 ATP molecules and 1 NADH are made. Because this phase takes place twice, one for each of the 3 carbon suagrs, it makes 4 ATP and 2 NADH. In step 5 of glycolysis, glucose (six-carbon) is converted to GAP and DHAP (both 3- carbons). GAP goes on in the glycolysis pathway. The other, DHAP, cannot go on through glycolysis directly; it is converted to GAP by triose phosphate isomerase. Focus on the "one step" part of the question. Question 27 5 / 5 pts (Fill in the blank) Use the following word bank to fill in the appropriate blanks. Not all word will be used; words can be used more than once. Word bank: one, two, three, four, five, six Glucose contains (A) carbon atoms. The oxidation of a glucose molecule utilizes (B) ATP. Later, the (C) three-carbon products of glycolysis produce (D) ATP by direct phosphorylation, which gives a net yield of two ATP. In addition, (E) NADH are produced in glycolysis. Your Answer: A) six B) two C) two D) four E) two A) six B) two C) two D)four E) two Question 28 4 / 5 pts (Short response) Consider the fatty which has 20 carbons (below). A. (2 pts) How many cycles of β -oxidation are required? Briefly explain. B. (2 pts) How many acetyl-CoA are produced? Briefly explain. C. (1 pts) How many NADH and FADH2 are produced from β -oxidation (only) of this molecule? Your Answer: A) 20/2= 10-1= 9 B) 10 acetyl-CoA are produced because 20/2= 10 C) 6 NADH and FADH2 A. 9 cycles are required for oleic acid. Each cycle removes two carbon units. ON the final cycle, two acetyl groups are produced. B. There are 10 acetyl-CoA groups produced. Two acetyl-CoA groups on the last cycle. C. There are 9 NADH and 9 FADH2 molecules produced. One per cycle. #3 is not correct. Question 29 7 / 10 pts (Short essay) The complete oxidative catabolism of fatty acids to form CO2 and H2O occurs in three phases. Describe the each of the three phases giving the important pathway in each phase and the energy molecules produced in each. Your Answer: phase 1= fattya cid undergoing b-oxidation to form acetly-coA phase 2= production of NADH and FAH2 form CAC in mitochondria phase 3= the electrons and hydrogen form the coenzymes passed to the ETC producing ATP. Answer: First phase: Fatty acid metabolism begins with b-oxidation which degrades the molecule into acetyl-CoA and also produces 1 FADH2 and 1 NADH molecules per cycle. Second Phase: the acetyl-CoA groups are shuttled through the citric acid cycle to generate GTP, NADH, FADH2 molecules along with the release of CO2. Third Phase: the NADH and FADH2 coenzymes are themselves oxidized in the mitochondria to yield ATP by a process called oxidative phosphorylation. Develop this a bit further. Include GTP in #2 and oxidative phosphorylation. EXAM 8 Question 1 3 / 3 pts True or False: The majority of reactions of the urea cycle occur in the cytosol. Correct! True False Question 2 3 / 3 pts True or False: FADH2 yields 2.5 ATP molecules after donating electrons and hydrogen atoms to the electron transfer chain (ETC). True Correct! False Question 3 3 / 3 pts True or False: ATP is invested in the urea cycle. Correct! True False Question 4 3 / 3 pts True or False: There are five complexes associated with the ETC. True Correct! False Question 5 0 / 3 pts True or False: In the production of ATP via ATP synthase, the H+ ions move from the mitochondrial matrix to the intermembrane space. You Answered True Correct Answer False Question 6 3 / 3 pts The urea cycle involves reactions (only those in the cyclic portion of the process). Correct! 4 5 6 8 10 Question 7 0 / 3 pts Which amino acids are involved in the urea cycle? A. Ornithine You Answered B. Aspartate C. Threonine Correct Answer D. Both A and B E. Both A and C Question 8 0 / 3 pts Fumarate reenters the mitochondrion as which of the following molecules? Correct Answer Malate You Answered Ornithine Citrulline Fumarase Ammonia Question 9 3 / 3 pts Urea is useful for excreting nitrogen from cells due to its: Correct! Ability to hydrogen bond with water Ability to form ions Large size Low melting point None of these Question 10 0 / 3 pts Which component of the urea cycle is also a member of the CAC? Correct Answer Fumarate Malate You Answered Acetyl-CoA Citrate None of the above Question 11 3 / 3 pts Oxidative deamination results in the removal of from amino acids. A. N2 B. NH + C. NO2 D. NH2 E. NH3 A Correct! B C D E Question 12 0 / 3 pts The following chemical species is . Ammonium Fumarate You Answered Arginine Argininosucccinate Correct Answer Urea Question 13 3 / 3 pts NADH donates electrons and H+ to complex . Correct! I II III IV V Question 14 3 / 3 pts Which of the ETC complexes do pump H+ ions? Complex I Complex II Complex III Both A and B Correct! Both A and C Question 15 3 / 3 pts What protein shuttles electrons from Complex III to Complex IV? NADH dehydrogenase Arginase Fumarase Cytochrome B Correct! Cytochrome C Question 16 3 / 3 pts What molecule transfers electrons and H+ from both Complex I and Complex II to Complex III? NADH FAD Cytochrome C Cytochrome B Correct! CoQ Question 17 0 / 3 pts In what portion of the mitochondrion does the CAC take place? Correct Answer Matrix Intermembrane space You Answered Inner membrane Outer membrane Both B and C Question 18 3 / 3 pts At which complex does the following reaction take place? O2 + 4e- + 4H+ → 2H2O Complex I Complex II Complex III Correct! Complex IV Both A and B Question 19 3 / 3 pts During the electron transport chain, protons are pumped from in the mitochondria. From the intermembrane space to the cytosol From the intermembrane space to the matrix Correct! From the matrix to the intermembrane space From outside of the cell to the cytosol From outside of the cell to the matrix Question 20 0 / 3 pts Energy released is utilized for the synthesis of ATP. You Answered In the formation of ATP In the digestion of proteins through the breakdown into the carbon skeleton In the degradation of carbohydrates Correct Answer As proton flow through ATP synthase None of the above Question 21 3 / 3 pts At which part of ATP synthase is ATP produced? A. FO B. F1 C. Axel D. Stator E. Both A and C A Correct! B C D E Question 22 3 / 3 pts An individual with the MERRF disease, tend to have symptoms of . Blood pressure issues headaches High cholesterol Correct! Muscle twitches None of the above Question 23 3 / 3 pts In mitochondria, the molecule that produces ATP is located in the . A. Intermembrane space B. Outer membrane Correct! C. Inner membrane D. Both A and B E. Both B and C Question 24 3 / 3 pts What process results in ATP formation? A. H2O in ATP synthase B. GTP is produced first C. Heat applied to ATP synthase D. Rotation of ATP synthase E. None of the above A B C Correct! D E Question 25 3 / 3 pts Which of the following is not a part of ATP synthase? A. F B. FO C. F1 D. F2 E. Both A and D A B C D Correct! E Question 26 2 / 5 pts (Fill in the blanks) Use the word bank to fill in the following blanks. In the word bank, each word or words is separated by semicolons. Words can be used more than once, and not all words will be used. Word bank: ADP and Pi; ATP; GTP; oxidative; reductive; citric acid cycle; electron transport chain; three; eight; ten Oxidative phosphorylation occurs in (A) phases using NADH and FADH2 generated from the (B) . Oxidative phosphorylation is the synthesis of (C) from (D) , using energy generated by the (E) reactions. Your Answer: A) oxidative B) electron transport chain C) ATP D) ADP E) oxidative A) three B) citric acid cycle C) ATP D) ADP and Pi E) electron transport chain "C" and "D" are correct. Question 27 6 / 10 pts Oxidative phosphorylation occurs in three phases. The first phase in the flow of electrons to from NADH and FADH2. What happens after this first phase is complete? Your Answer: The second phase then takes place which includes the genertation of proton H+ gradient across the inner mitochondrial membrane. The thrid phase includes transfer of electrons and H+ to CoQ but from FADH2. The chemical reactions of the ETC provide energy to pump H+ ions from the mitochondrial matrix into the intermembrane space. The reactions also provide electrons and H+ to convert oxygen into water. The net result is that the H+ gradients permit a flow H+ to rotation ATP synthase, producing ATP. Develop the ATP synthesis a bit further. Question 28 7 / 10 pts Describe the critical structure of the mitochondrion that are important for the production of ATP. Your Answer: The chemiosomatic theory is the theory by Peter Mitchell used to describe the formation of ATP by ATP synthase, electrons flowing through the ETC. The chemical reactions of the ETC provide the energy to create a H+ gradient. The matric inside is more negative which is higer H+ and the lower matrix is more basic and has higher OH-. The H+ flow drives ATP production. f1 region has 3 ATP sites. Fo region has turns while F1 is static. If Fo is inhibited, ATP production halts. If ETC is inhibited, ATP production halts. This organelle is the central hub of the energy production in the cell and has a complicated structure including two membranes. The mitochondrion has an outer membrane and an inner membrane. The outer membrane is a bilayer that has porin proteins that permit ions and molecules to cross into the intermembrane space. The intermembrane space is the solution between the outer and inner membranes. The inner membrane is highly selective bilayer permitting only select ions and molecules to cross. The selectivity is crucial for maintaining specific concentrations of H+, ATP, and other species in the mitochondrial matrix. Also, the inner membrane contains the protein complexes of the electron transport chain, which accepts the electrons from the coenzymes. The matrix is the innermost space of mitochondrion where the citric acid cycle occurs along portions of fatty acid oxidation and the urea cycle. Once the NADH and FADH2 are produced by the citric acid cycle they are in proximity to the electron transport chain, so that donation of electrons and hydrogen ions is efficient. FINAL EXAM Question 1 3 / 3 pts True or False: Hydrogen is called the superglue of the chemical world. True Correct! False Question 2 0 / 3 pts True or False: Small elements, such as nitrogen, are common in biomolecules. Correct Answer True You Answered False Question 3 3 / 3 pts True or False: The time it takes for a compound to flow through a metabolic pathway is called the flux. Correct! True False Question 4 0 / 3 pts True or False: Proteins, carbohydrates, and fats all get broken down into NADH and FADH2 in energy production. Correct Answer True You Answered False Question 5 3 / 3 pts True or False: A fat is a lipid molecule that is a liquid at room temperature. True Correct! False Question 6 3 / 3 pts In RNA, guanine always pairs with . Thymine Guanine Correct! Cytosine Uracil Both A and B Question 7 3 / 3 pts Water is considered a polar solvent due to attractive forces known as hydrogen bonds. A hydrogen bond is . A bond that is stronger than a covalent bond Correct! An attractive force between molecules where partially positive hydrogen atoms are attracted to partially negative atoms of F, O, or N. The polar O–H bond in water An ionic bond between H and another atom A covalent bond between H and O Question 8 0 / 3 pts Which of the following is the structure of ATP? Correct Answer A You Answered B C D E Question 9 3 / 3 pts Which attribute contributes to water’s unusual properties? The geometry of the molecule The polarity of the O-H bonds The ability of water molecules to hydrogen bond The bond angle of water Correct! All of the answers are correct Question 10 3 / 3 pts The H+ concentration of a solution is 7.9 x 10-13 M. What is the pH? -6.70 6.