132 Version Exam 1 sathasivan (48985) This print-out should have 51 questions. Multiple-choice questions may continue on the next column or page nd all choices before answering. 001 10.0 points A single covalent chemical bond represents the sharing of how many electrons? 1. Six 2. Two correct 3. Four 4. Three 5. One Explanation: 002 10.0 points Which of the following is the correct ranking of the biological hierarchy? select in the order from highest to lowest in terms of such hierarchy. 1. tissue, cell, organ, organelle and organism 2. organism, organ, organelle, cell and tissue 3. cell, nuclear membrane, DNA, phosphate and oxygen correct 4. cell, tissue, organ, nucleus and organelle 5. nucleus, cell, macromolecule, carbon and tissue Explanation: 003 10.0 points D)
H H OH HO H OH
1
2.
1 100 5 3. 7 4. nearly the same concentration 5. 100 times correct
Explanation: Recall 004 10.0 points
Which of the the molecules A)
O CH2 CH2 P O H2 C O O C CH O C O CH2 O N (CH3 )3
B)
O C H H H H H H C C C C C C C H
OH H H H H H H H
H2 C H2 C H2 C H2 C H2 C H2 C H3 C
CH2 CH2 CH2 CH CH CH2 CH2
H
CH3
C)
OO O O CH2 OH OH H H O H OH H CH2 OH O
O O
Compared with a pH of 7, a solution of pH 5 has what times/fraction of the hydrogen concentration? 1. twice
OH H OH OH
Version 132 Exam 1 sathasivan (48985) E)
HOCH2 H OH O
2
F)
OH H H H
CH2 OH OH H OH H OH H OH O C C C C C C H OH H OH OH OH
5. A and F Explanation: Comprehension and application 005 10.0 points Animals combine 1000 of the monomer
CH2 OH H H OH HO H OH H OH OH
H
HO
OH
G)
H C H C C C C C H
O OH H H OH OH
H)
H H HO H H H
HO HO H H
and store them as 1. starch.
I)
H3 N+
H O C CH2 CH2 S CH3 H C O
J)
H3 C H
C
C
CH3 H
2. protein. 3. glycogen. correct
K)
O P O OH
4. DNA. 5. steroid. Explanation: First you need to identify the monomer as a simple sugar and then gure out that a polymer of 1000 such monomers will make a polysaccharide. Then recall the storage polysaccharide in animal glycogen. Only plants make starch as storage polysaccharide.
O
L)
H H H
C C C H
OH OH OH
M)
H2 N
H O C C OH CH2 SH
N)
N HC
NH2 C C C N H N CH
O)
H H N H H C C OH
N
could be joined together by an ester linkage? 1. I and O 2. K and N 3. B and L correct 4. G and H
006 10.0 points You have eaten a potato chip that contained starch made of 10,000 glucose monomers combined together. After complete digestion through hydrolysis, this will yield I) 10,000 glucose molecules. II) 10,000 water molecules. III) 9,999 water molecules. IV) 9,999 glucose molecules. 1. III and IV only 2. I and II only
Version 132 Exam 1 sathasivan (48985) 3. I and III only 4. I only correct 5. II only Explanation: Hydrolysis is the breakdown of a larger molecule to simpler molecule. It uses water and does not form any water molecules. Hence a complete digestion of a polymer with 10,000 monomers will yield only 10,000 monomers. To go into further details, it will utilize 9999 water molecules to break down this larger polymer. 007 10.0 points Why do carbon atoms have a high number of covalent bonds? 1. The valence of carbon is 4. correct 2. Carbon has eight electrons. 3. Carbon has eight protons. 4. Carbon has six to eight neutrons. 5. Carbon ionizes to attract other atoms. Explanation: Factual recall 008 10.0 points In condensation synthesis, the atoms that make up a water molecule are derived from 1. carbohydrates. 2. enzymes. 3. the atmosphere. 4. only one of the reactants. 5. both the reactants. correct Explanation: 009 10.0 points Which of the following cannot be answered by scientic experimentation? 1. Does God exist? correct 2. How did humans arise? 3. How do red blood cells carry oyygen? 4. What is the basis of heredity? 5. Why do humans have a nite life span? Explanation: Comprehension
3
010 10.0 points The molecular weight of NaOH is 40. To make a 0.5 M solution of NaOH, you should have 1. 4 g of NaOH dissolved in 1 L of solution. 2. 40 g of NaOH dissolved in 1 L of solution. 3. 40 g of NaOH dissolved in 100 mL of solution. 4. 4 g of NaOH dissolved in 100 mL of solution. 5. 4 g of NaOH dissolved in 200 mL of solution. correct Explanation: 4 g dissolved in 200 mL: 4g = 0. 5 M 200 mL is the same as 20 g dissolved in 1000 mL: 20 g = 0. 5 M 1000 mL 011 10.0 points Of the following compounds containing 1 H, 12 C, and 16 O, the one with the greatest number of molecules in a sample with a mass of 2 grams would be 1. C2 H5 OH.
Version 132 Exam 1 sathasivan (48985) What happens when water vaporizes? 2. C6 H12 O6 . 1. ionic bonds are formed 3. HCOOH. 2. polar covalent bonds are broken 4. CO2 . 3. hydrogen bonds are broken correct 5. CO. correct Explanation: 012 10.0 points Consider the following.
H H C H HO H H H C C C C C H OH H OH OH OH HO H H H O H C C C C C C H OH O
4
4. hydrogen bonds are formed 5. bonds are not broken nor formed Explanation: When water vaporizes, H-bonds between water molecules break to form water vapor. 014 If 128 of
H OH OH OH
10.0 points
CH2 OH
H H OH HO H
OH H OH OH
were covalently joined together, what would be the resulting molecule(s)? 1. 127 water molecules 2. a polysaccharide and 127 water molecules correct 3. a polypeptide and 127 water molecules 4. a polysaccharide and a polypeptide 5. a polypeptide 6. a polysaccharide Explanation: 015 10.0 points
glucose fructose What is the dierence between these two molecules? 1. the arrangement of carbon, hydrogen, and oxygen atoms correct 2. the composition of the elements C, H and O 3. the types of carbon, hydrogen, and oxygen atoms 4. the number of carbon, hydrogen, and oxygen atoms 5. the number of covalent bonds Explanation: Two representations for C6 H12 O6 013 10.0 points
Which molecule can decrease the concentration of hydrogen ions in a solution?
Version 132 Exam 1 sathasivan (48985) H 1. H C H 2. None of these H 3. H H C H H 4. O H C H H 5. O H C H H 6. H C H Explanation: 016 10.0 points Polymerase Chain Reaction (PCR) is a process to make multiple copies of DNA in a small tube by adding DNA, dNTPs, enzymes and a few other chemicals. This is known as what reaction/process? 1. an in situ 2. a revolutionary 3. an in vitro correct 4. an evolutionary 5. an in vivo Explanation: Adding various chemicals to a test tube and conducting reactions without living cells are considered an in vitro reaction. O H C H OH C OH C H N H correct O C H C H H
5
017 10.0 points Which of the following is an example of hydrolysis reaction? 1. the synthesis of a nucleotide from a phosphate, a ribose sugar, and a nitrogen base 2. the reaction of two glucose molecules to form a disaccharide 3. the combination of three amino acids to form a tripeptide 4. the breakdown of a fat to form glycerol and amino acids 5. the breakdown of a triglyceride to form glycerol and fatty acids correct Explanation: Comprehension and application 018 (part 1 of 2) 10.0 points The molecule CH2 CH2 P O H2 C O O C CH O C O CH2 O N (CH3 )3
H2 C H2 C H2 C H2 C H2 C H2 C H3 C is a
CH2 CH2 CH2 CH CH CH2 CH2 CH3
Version 132 Exam 1 sathasivan (48985) creases. 1. protein. 2. steroid. 3. monoglyceride. 4. triglyceride. 5. phospholipid. correct Explanation: Recall and application 019 (part 2 of 2) 10.0 points Which part of a cell will contain this molecule as its main component? 1. cytoplasm 2. cytoskeleton 3. cell membrane correct 4. nucleus 5. cell wall Explanation: The above molecule is a phospholipid; they are major components of cell membranes. 020 10.0 points What happens when a vegetable oil is hydrogenated? 1. The oil becomes liquid at room temperature. 2. The number of carbon atoms in the oil molecule increases. 3. The number of carbon-carbon double bonds in the oil molecules decreases. correct 4. The number of carbon atoms in the oil molecule decreases. 5. The ratio of carbon to hydrogen in022 10.0 points The molecule HHHHHHH O H is a 1. saturated fatty acid. 2. polyunsaturated fatty acid. correct 3. protein. 4. polysaccharide. 5. monounsaturated fatty acid. C H C H C C C H C C C OH
6
Explanation: Hydrogenation adds hydrogens to the carbon skeleton and the number of C-C double bonds decreases and the oil becomes solid at room temperature. 021 10.0 points Which of the following is true of optical isomers? 1. Their atoms and bonds are arranged in dierent ways. 2. They have the same chemical properties. 3. They have dierent molecular formulas. 4. They vary in arrangement around a double bond. 5. They have an asymmetric carbon that makes them mirror images. correct Explanation: Factual recall
Explanation: The two double bonds on the hydrocarbon and the carboxyl group indicate that this is polyunsaturated fatty acid.
Version 132 Exam 1 sathasivan (48985) 023 10.0 points Buers help maintain pH by 1. making the solution more basic. 2. making the solution more acidic. 3. releasing OH in basic solutions. 4. accepting or donating H+ ions when needed. correct 5. diluting the solutes more evenly. Explanation: Comprehension. 024 10.0 points The statement that regular exercise will improve your health signicantly is an example of 1. a statement that can be disproved. 2. a statement derived from a belief. 3. inductive reasoning. 4. a prediction that cannot be tested. 5. deductive reasoning. correct Explanation: Comprehension 025 10.0 points Humans can digest starch but not cellulose bers because humans have enzymes that can digest only 1. -1,4 glycosidic linkages but not -1,4 glycosidic linkages. 2. peptide bonds but not glycosidic bonds. 5. antibiotic X; antibiotic Y 3. nonpolar covalent bonds but not polar covalent bonds. 4. ionic bonds not but covalent bonds. Explanation: 028 10.0 points The two molecules
7
5. -1,4 glycosidic linkages but not -1,4 glycosidic linkages. correct Explanation: 026 10.0 points A compound contains several hydroxyl groups, which is its only functional group. As such, what property will it have? 1. It will be an acid. 2. It will be a strong base. 3. It should dissolve in water. correct 4. It is hydrophobic. 5. It should dissolve in a non-polar solvent. Explanation: The hydroxyl group is polar and polar molecules easily dissolve in water. 027 10.0 points A scientist studied the eect of several new drugs (antibiotics X, Y and Z) to kill anthrax bacteria growing on petri plates with proper nutrients. The treatments in this study, applied to the bacterial media to compare with the currently used antibiotic are as follows: antibiotic X antibiotic Y antibiotic Z water currently used antibiotic Which treatments are considered as negative and positive controls? 1. antibiotic Z; water 2. currently used antibiotic; antibiotic X 3. water; currently used antibiotic correct 4. antibiotic Y; antibiotic Z
Version 132 Exam 1 sathasivan (48985)
H H C H H C C H H C H H C H H H C C H C H H H H
8
2. CO2 3. CH4 4. O2 5. CH3 OH correct Explanation: 031 10.0 points If you study the eect of drugs on cancer cells in a test tube, the results can be extrapolated to possible eectiveness in treating a cancer patient. This is an example of the application of which of the following to the study of cancer drugs? 1. the cell theory 2. evolution 3. reductionism correct 4. natural selection 5. negative control 6. holism Explanation: Use of cells to screen drugs is an eective and ecient method to screen potential drugs to treat patients. 032 10.0 points A chemist wishes to make an organic molecule non-acidic. Which functional group should be removed in the molecule, if it is present? 1. amino 2. carbonyl 3. hydroxyl 4. sulfhydryl
are best described as 1. structural isomers. 2. optical isomers. 3. radioactive isotopes. 4. isotopic isomers. 5. geometric isomers. correct Explanation: Comprehension and application 029 10.0 points What would be the pH of a solution with a hydroxide ion concentration of 1010 M? 1. 14 2. 8 3. 10 4. 4 correct 5. 2 Explanation: If the hydroxide ion concentration is 1010 , the hydrogen ion concentration will 1014 be 10 = 104 M and the pH will be 4. 10 030 10.0 points Which of the following molecules have polar covalent bonds 1. C2 H6
Version 132 Exam 1 sathasivan (48985)
H
9
5. carboxyl correct
H H
C C
H H H H H
H C H C H H C
H
C C
Explanation: Comprehension and application 033 10.0 points Which of the following structures will be most non-polar?
H H C O H
H H
C C
H
C H H H H C
H H H H H H H H
C C
C C
H
1.
H
C C
H
C H
H
HO
CO
is commonly found in
H
1. cellulose.
C O
2.
H
2. olive oil. correct 3. lysozyme.
H
H C C O H
3.
H
4. DNA. 5. RNA. Explanation:
H
4.
H
N
O
H
035 10.0 points What happens when a vegetable oil is hydrogenated? 1. The ratio of carbon to hydrogen increases. 2. The oil becomes liquid at room temperature. 3. An increase in the number of carboncarbon double bonds in the oil molecules.
H
5.
H
C H
H
correct
Explanation: Comprehension CH4 is methane a hydrocarbon. Oxygen or nitrogen make structures polar. 034 The molecule 10.0 points
4. The number of hydrogen atoms in the oil molecule decreases. 5. The number of hydrogen atoms in the oil molecule increases. correct Explanation:
Version 132 Exam 1 sathasivan (48985) Hydrogenation adds hydrogens to the carbon skeleton and the number of C-C double bonds decreases and the oil becomes solid at room temperature. 036 10.0 points One mole (mol) of a substance is equal to 1. the molecular weight of the substance expressed in grams. correct 2. 6.02 grams dissolved in 1 L of solution. 3. the molecular weight of a substance expressed in mL. 4. 6.02 1023 grams of the substance. 5. 100 g of the substance dissolved in 1 L of solution. Explanation: Comprehension and recall 037 10.0 points Hydrogen bonds will be formed between 1. Ca and Cl in CaCl2 . 2. C and O in carbon dioxide. 3. ammonia and a water molecule. correct 4. two oxygen atoms. 5. two hydrogen atoms. Explanation: The hydrogen in water and the nitrogen in ammonia or the hydrogen in ammonia and the oxygen in water will make H-bonds. 038 10.0 points When an atom such as nitrogen that has ve electrons in its valence shell interacts with three atoms such as hydrogen with one electron in their valence shells, it tends to form a molecule with 1. H-bonds 2. polar covalent bonds. correct 3. hydrophobic interactions. 4. ionic bonds. 5. non-polar covalent bonds. Explanation:
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039 10.0 points One liter of household diluted bleach with pH 11 has how many more OH ions than 1 L of diluted vinegar with pH 6? 1. 11 times more 2. 10,000 times more 3. 10 times more 4. 6 times more 5. 100,000 times more correct Explanation: For each unit of pH increase, there is a ten-fold increase in OH ion concentration. 040 10.0 points The molecular mass of glucose is 180 and that of NaOH 40. Which solution contains 100 mM glucose and 10 mM NaOH? 1. 100 mL solution containing 180 g of glucose and 40 g of NaOH 2. two liter solution containing 18 g of glucose and 4 g of NaOH 3. one liter solution containing 18 g of glucose and 400 mg of NaOH correct 4. one liter solution containing 180 g of glucose and 40 g of NaOH 5. one liter solution containing 180 g of glucose and 4 g of NaOH Explanation:
Version 132 Exam 1 sathasivan (48985) 041 10.0 points Which of the following statements is (are) true about the -OH group? 1. It is an aldehyde and is hydrophobic. 2. It has properties of a base. 3. It is negatively charged and hence reactive. 4. It is an alcohol and is hydrophilic. correct 5. It has properties of an acid. Explanation: 042 The molecule
H3 C
11
5. two more neutrons than carbon-12. correct Explanation: An atom of a given element has usually an equal number of protons and neutrons. When it has more neutrons, it is called an isotope. Both carbon-12 and its isotope, carbon-14 have the same number of protons but carbon14 has two more neutrons. 044 10.0 points Why are water molecules able to form hydrogen bonds? 1. Oxygen has 6 valence electrons. 2. Oxygen has a weak negative charge and the hydrogen has a weak positive charge. correct
10.0 points
CH2 CH2 C H3
H2 H3 C C H3 H CH3 H CH3 H H H H H C C C C C C C C C C C C C C C C C C C C C C C C H2 C C H2 C C H H H H H CH3 H CH3 H H3 CH3 C H2
3. A water molecule is shaped like a tetrahedron. 4. Hydrogen atoms in a water molecule have weak negative charges. 5. An oxygen atom in a water molecule has a strong positive charge. Explanation: The hydrogen in one water molecule and the oxygen in the adjoining water molecule will make H-bonds. 045 10.0 points The molecular weight of glucose is 180 g. Which of the following solution contains 1 M glucose? 1. 100 g of glucose dissolved in 1 L of water 2. 180 g of glucose mixed with 1 L of water 3. 180 g of glucose dissolved in 100 g of water 4. 18 g of glucose dissolved in 100 mL solution correct
can be grouped as 1. glycerol. 2. an amino acid. 3. a nucleotide. 4. a fatty acid. 5. a carotenoid. correct Explanation: 043 10.0 points The major dierence between carbon-12 and carbon-14 14 C is that carbon-14 has 6 1. one more electron than protons. 2. two more protons than carbon-12. 3. two more electrons than carbon-12. 4. one more proton than electrons.
12 6C
Version 132 Exam 1 sathasivan (48985) 5. a steroid correct 5. 180 mg of glucose dissolved in 1 L of water Explanation: 18 g glucose in 100 mL is the same as 180 g in 1000 mL or 1 L. 180 g of glucose mixed with 1 L of water is not correct because if you mix 180 g glucose and 1 L water, the nal volume will be greater than 1 L, and the concentration will be lower. 046 10.0 points What is the solute molecule that is most likely soluble in water? 1. nonpolar 4. 0.342 g 2. hydrophobic 5. 3.42 g correct 3. polar uncharged only 4. polar, either charged or uncharged correct 5. charged only Explanation: Comprehension 047 10.0 points Consider the structure H3 C H3 C H3 C CH3 Explanation: 049 10.0 points What characterizes a eukaryotic cell? 1. the presence of DNA and RNA 2. the lack of cell wall and membranes 3. the presence of chloroplast 4. the presence of nucleoid region 5. the presence of ribosomes
12
Explanation: Steroids have four fused carbon rings and various functional groups attached to them. 048 10.0 points The MW of sucrose is 342. How many grams are needed to make 100 mL of 100 mM sucrose solution? 1. 100 g 2. 34.2 g 3. 342 g
6. the lack of nucleus or nuclear membrane 7. the presence of a nucleus surrounded by a nuclear envelope correct Explanation: All eukaryotic cells have a well-dened nucleus with a nuclear membrane. 050 10.0 points Which of the following is not characteristic of a liquid triglyceride (an oil)? 1. forms micelles in water due to immiscibility
HO What is it? 1. a starch molecule 2. a nucleotide 3. a cellulose molecule 4. a protein
Version 132 Exam 1 sathasivan (48985) 2. more likely to be degraded than stored in humans 3. contains more calories per gram than a carbohydrate 4. produced mostly in plants 5. contains only saturated fatty acids correct Explanation: Recall 051 10.0 points A solution is found to contain 106 M hydroxide ions. What is the best description for the solution? 1. neutral 2. slightly basic correct 3. strongly basic 4. slightly acidic 5. strongly acidic Explanation: Comprehension and application
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