PRACTICE EXAM 1
Try to answer questions first. The answers are found at the end of the exam.
Chapter 1
1. Consider the following statement: "If all vertebrates have backbones, and turtles are vertebrates, then turtles have backbones." This statement is an example of
A) a hypothesis.
B) discovery science logic.
C) rationalization.
D) deductive reasoning.
E) inductive reasoning.
2. A hypothesis is
A) the same as a theory.
B) a tentative answer to some question.
C) an explanatory idea that is broad in scope and supported by a large body of evidence.
D) a widely accepted idea about a phenomenon.
E) a widely accepted theory that is broad in scope and supported by a large body of evidence.
3. You notice that over the past month, many students on campus have started wearing a new style of school sweatshirt. You think to yourself that perhaps the bookstore has recently started selling this new sweatshirt style. This prediction is an example of
A) an experimental question.
B) a type of observation.
C) a hypothesis.
D) an experiment.
E) a type of control.
4. A theory is
A) an idea that has been proven.
B) a concept in the early stages that still needs to be tested.
C) a belief that has been accepted by all scientists as fact.
D) a description of a belief that invokes the supernatural.
E) an explanation of an idea that is broad in scope with multiple lines of evidence.
5. To be scientifically valid, a hypothesis must be
A) phrased as a question.
B) based on faith.
C) controlled.
D) reasonable.
E) testable and falsifiable.
6. A scientist performs a controlled experiment. This means that
A) the experiment is repeated many times to ensure that the results are accurate.
B) the experiment proceeds at a slow pace to guarantee that the scientist can carefully observe all reactions and process all
experimental data.
C) two experiments are conducted, one differing from the other by only a single variable.
D) two experiments are conducted, one differing from the other by two or more variables.
E) one experiment is performed, but the scientist controls the variables.
Scenario Questions: After reading the following paragraph, answer the question(s) below.
The National Institutes of Health (NIH) set up a study to determine whether large doses of vitamin C would shorten the length of time it takes to recover from a cold. Three thousand volunteers were split into two groups. For two weeks, members of Group A took 3,000 mg of vitamin C daily. Group B received 3,000 mg of a placebo. At the end of the two-week period, the researchers inserted live cold viruses directly into the noses of all the volunteers. The volunteers in both Group A and B continued to take their daily pills. All the volunteers got colds, and there was no significant difference in the length of time the colds lasted.
1. Which was the experimental group?
A) Group A only
B) Group B only
C) all 3,000 volunteers
D) half of Group A and half of group B
E) the researchers that inserted the cold virus
2. To have confidence that the results of the experiment were valid, you'd also want to know
A) the genders of the volunteers.
B) whether any volunteers had colds at the start of the experiment.
C) whether the volunteers exercised daily.
D) whether the volunteers all worked for the same company.
E) what the volunteers ate during the experiment.
Chapter 2
1. The four most common elements in living organisms are
A) C, H, O, Fe.
B) C, H, O, Na.
C) C, H, O, N.
D) C, N, O, Na.
E) Fe, N, O, Ca.
2. In the equation 2 H2+ O2→ 2 H2O,
A) H2, O2, and H2O are all compounds.
B) H2, O2, and H2O are all elements.
C) only H2O is a compound.
D) only H2 and O2 are compounds.
E) H2, O2, and H2O are all trace elements.
3. Which of the following particles is found in the nucleus of an atom?
A) protons and neutrons
B) protons and electrons
C) only neutrons
D) only protons
E) only electrons
4. What is the atomic mass of an atom that has 6 protons, 6 neutrons, and 6 electrons?
A) 6
B) 8
C) +1
D) 12
E) 18
5. A radioactive isotope is an isotope that
A) is stable.
B) decays.
C) has more protons than the common variant of the element.
D) has more electrons than the common variant of the element.
E) has the same atomic mass, but a different atomic number than the common variant of the element.
6. Table salt is formed when
A) chlorine gives an electron to sodium.
B) a hydrogen bond forms between sodium and chlorine.
C) sodium and chlorine share electrons to form a bond.
D) sodium crystals combine with chlorine crystals.
E) sodium donates its single outer electron to chlorine
7. What is the fundamental difference between covalent and ionic bonding?
A) In a covalent bond, the partners have identical electronegativity; in an ionic bond, one of them is more electronegative.
B) In a covalent bond, the partners share a pair of electrons; in an ionic bond, one partner accepts electrons from the other.
C) In covalent bonding, both partners end up with filled outer electron shells; in ionic bonding, one partner does and the
other does not.
D) Covalent bonding involves only the outermost electron shell; ionic bonding also involves the next electron shell inside
the outermost shell.
E) Covalent bonds form between atoms of the same element; ionic bonds form between atoms of different elements.
8. The hydrogen atoms of a water molecule are bonded to the oxygen atom by ______bonds, whereas neighboring water molecules are held together by ______bonds.
A) hydrogen . . . ionic
B) hydrogen . . . polar covalent
C) polar covalent . . . hydrogen
D) ionic . . . covalent
E) polar covalent . . . ionic
9. The temperature of evaporation is much higher for water than for alcohol. Without knowing more about the chemistry of alcohol, which of the following is the most logical chemical explanation for this phenomenon?
A) Ionic bonds form between alcohol molecules. These are the weakest type of bond and are easier to break than the
hydrogen bonds between water molecules.
B) Alcohol has a higher surface tension than water. This means that alcohol molecules can easily break away from other
alcohol molecules and evaporate at a lower temperature.
C) Alcohol molecules are more cohesive than water molecules. This means that as alcohol molecules evaporate, they pull
other alcohol molecules into the air along with them.
D) Fewer hydrogen bonds form between alcohol molecules. As a result, less heat is needed for alcohol molecules to break away from solution and enter the air.
E) Water is a better solvent than alcohol. Therefore, alcohol can break covalent bonds easily and will not be restricted
from evaporating from its solute.
10. A solution with a pH of 7 is
A) strongly acidic.
B) weakly acidic.
C) neutral.
D) weakly basic.
E) strongly basic.
11. Household ammonia has a pH of 12; household bleach has a pH of 13. Which of the following statements about them is true?
A) Both of these substances are strong acids.
B) The ammonia has 10 times as many OH- ions as the bleach.
C) The ammonia has 10 times as many H+ ions as the bleach.
D) A solution that could buffer the bleach and ammonia would remove excess OH- ions.
E) The ammonia has 10 times as many OH- ions as the bleach, and a solution that could buffer the bleach and ammonia
would remove excess OH- ions.
12. Which of the following hypotheses would be supported if liquid water were found on Mars and contained evidence of bacteria-like organisms?
A) Life must evolve in the presence of oxygen.
B) The chemical evolution of life is possible.
C) Life on Earth must have originated on Mars.
D) Life is guided by intelligent design.
E) Life spontaneously arises from the decaying flesh of organisms.
13. What change is occurring in this figure?
A) Sodium is gaining an electron.
B) Chlorine is losing an electron.
C) Sodium is becoming negatively charged.
D) Sodium is filling its third electron shell.
E) Chlorine is filling its third electron shell.
Scenario Questions: After reading the following paragraph, answer the question(s) below.
You've been experiencing acid indigestion lately, and you'd like a quick fix for the problem. You do a little research on the Internet and discover that your problem is caused by excess stomach acid. In the pharmacy aisles, however, you're having a little trouble deciding what to purchase to address the problem. At the pharmacy counter, the clerk recommends that you purchase Pepcid-AC® or Alka-Seltzer® tablets.
1. If you could check the pH of the recommended tablets, you would expect it to be
A) higher than 7.
B) lower than 7.
C) exactly 7.
D) pH neutral.
E) either C or D.
2. If you were able to chemically analyze your stomach fluids 30 minutes after taking two tablets, you would find
A) more hydrogen ions.
B) fewer hydrogen ions.
C) the same number of hydrogen ions.
D) that the pH in your stomach has decreased.
E) a greater number of covalent bonds.
Chapter 3
1. You now know that the old cliché "oil and water don't mix" is true. Why?
A) Oil exhibits polarity and water does not.
B) Water exhibits polarity and oil does not.
C) Oil is hydrophilic.
D) Water is hydrophobic.
E) Oil is an organic compound and water is not.
2. Propanol and isopropanol are isomers. This means that they have
A) the same molecular formula, but different chemical properties.
B) different molecular formulas, but the same chemical properties.
C) the same molecular formula and the same chemical properties.
D) the same number of carbon atoms, but different numbers of oxygen and hydrogen atoms.
E) the same molecular formula, but represent different states of the compound.
3. Which of the following contains a carboxyl and an amino group?
A) amino acids
B) fats
C) sugars
D) ATP
E) vinegar
4. Which of the following statements about the monomers and polymers found in living organisms is false?
A) Cells typically make all of their macromolecules from a set of 40-50 common monomers and a few other ingredients
that are rare.
B) The monomers used to make polymers are essentially universal.
C) Monomers serve as building blocks for polymers.
D) DNA is built from just four kinds of monomers.
E) Monomers are joined together by the process of hydrolysis.
5. Which list below consists of only polymers?
A) sugars, amino acids, nucleic acids, lipids
B) proteins, lipids, nucleic acids, amino acids
C) proteins, lipids, nucleic acids, polysaccharides
D) proteins, lipids, nucleotides, sugars
E) polysaccharides, lipids, amino acids, nucleic acids
6. A molecule with the formula C55H110O55 is probably a(n)
A) oil.
B) steroid.
C) wax.
D) protein.
E) polysaccharide.
7. High-fructose corn syrup is composed primarily of a polysaccharide called
A) sucrose.
B) starch.
C) hydrocarbon.
D) cellulose.
E) lactose.
8. An oil may be converted into a substance that is solid at room temperature by
A) addinghydrogens, decreasing the number of double bonds in the molecules.
B) removing water, causing a dehydration synthesis reaction to occur.
C) removinghydrogens, increasing the number of double bonds.
D) cooling it, so that double bonds form and the fats solidify.
E) adding water and shaking it vigorously.
9. A diet high in animal products and hydrogenated vegetable margarine may increase the risk for atherosclerosis. This is because
A) most animal fats are unsaturated and most hydrogenated vegetable margarines contain high levels of steroids.
B) most hydrogenated vegetable margarines are hydrogenated oils and most animal products contain high levels of
phospholipids.
C) most animal fats are used for energy storage and most hydrogenated vegetable margarines contain high levels of
unsaturated fats.
D) most animal fats are saturated and many hydrogenated vegetable margarines contain high levels of trans fats.
E) most animal products contain high levels of unsaturated oils and most hydrogenated vegetable margarines contain
anabolic steroids.
10. Fatty acids are
A) composed of carbon, hydrogen, and oxygen in a 1:2:1 ratio.
B) composed of carbon, hydrogen, glycerol, and a phosphate group.
C) hydrophobic.
D) composed of four linked rings.
E) components of DNA.
11. Fatty acids with double bonds between some of their carbons are said to be
A) unsaturated.
B) saturated.
C) completely hydrogenated.
D) triglycerides.
E) monoglycerides.
12. A major type of lipid found in cell membranes is
A) cellulose.
B) triglycerides.
C) phospholipids.
D) glycerol.
E) waxes.
13. Amino acids can be distinguished from one another by
A) the number of R groups found on the amino acid molecules.
B) the chemical properties of their R groups.
C) the type of bond between the R group and the rest of the amino acid molecule.
D) the chemical properties of their amino and carboxyl groups.
E) the number of alpha carbons present in the amino acid molecules
14. Glucose molecules are to starch as ______are to proteins.
A) oils
B) amino acids
C) fatty acids
D) monosaccharides
E) lards
15. Which of the following characteristics of protein will remain intact if the protein is denatured?
A) the shape of the protein
B) the function of the protein
C) the solubility of the protein in water
D) the number of amino acids in the protein
E) the binding properties of the protein
16. DNA differs from RNA because DNA
A) contains thymine in place of uracil.
B) consists of a single rather than a double polynucleotide strand.
C) contains the sugar ribose rather than the sugar deoxyribose.
D) contains phosphate groups not found in RNA.
E) is always double-stranded, while RNA is never double-stranded.
17. Genetic information is encoded in the
A) quaternary structure of a protein.
B) sequence of nucleotides in DNA.
C) degree of saturation of fatty acids.
D) length of glycogen.
E) linear sequence of amino acids in a polypeptide.
18. How are the two amino acids attached together in the above figure?
A) amino group to amino group
B) amino group to carboxylic acid group
C) carboxylic acid group to carboxylic acid group
D) carbon atom to carbon atom
E) through a hydrolysis reaction
Scenario Questions: After reading the following paragraph, answer the question(s) below.
You're the manager of a factory that produces enzyme-washed blue jeans (the enzymes lighten the color of the denim, giving a "faded" appearance). When the most recent batch of fabric came out of the enzyme wash, however, the color wasn't light enough to meet your standards. Your quality control laboratory wants to do some tests to determine why the wash enzymes didn't perform as expected.
1. Which hypothesis is most likely to be productive for their initial investigation?
A) The nucleotide chain of the enzymes may be incorrectly formed.
B) The dye in the fabric may have hydrolyzed the fatty acids in the enzymes.
C) The polysaccharides in the enzymes may have separated in the wash water.
D) The three-dimensional structure of the proteins may have been altered.
E) There may not have been enough phospholipids for the volume of fabric.
2. Based on your understanding of enzyme structure, which of the following would you recommend that they also investigate?
A) the temperature of the liquid in the washing vat
B) the pH of the liquid in the washing vat
C) the manufacturer of the fabric
D) how long the fabric has been in storage
E) the primary structure of the enzyme
ANSWERS TO PRACTICE EXAM
Chapter 1
1. Consider the following statement: "If all vertebrates have backbones, and turtles are vertebrates, then turtles have backbones." This statement is an example of
A) a hypothesis.
B) discovery science logic.
C) rationalization.
D) deductive reasoning.
E) inductive reasoning.
2. A hypothesis is
A) the same as a theory.
B) a tentative answer to some question.
C) an explanatory idea that is broad in scope and supported by a large body of evidence.
D) a widely accepted idea about a phenomenon.
E) a widely accepted theory that is broad in scope and supported by a large body of evidence.
3. You notice that over the past month, many students on campus have started wearing a new style of school sweatshirt. You think to yourself that perhaps the bookstore has recently started selling this new sweatshirt style. This prediction is an example of
A) an experimental question.
B) a type of observation.
C) a hypothesis.
D) an experiment.
E) a type of control.
4. A theory is
A) an idea that has been proven.
B) a concept in the early stages that still needs to be tested.
C) a belief that has been accepted by all scientists as fact.
D) a description of a belief that invokes the supernatural.
E) an explanation of an idea that is broad in scope with multiple lines of evidence.
5. To be scientifically valid, a hypothesis must be
A) phrased as a question.
B) based on faith.
C) controlled.
D) reasonable.
E) testable and falsifiable.
6. A scientist performs a controlled experiment. This means that
A) the experiment is repeated many times to ensure that the results are accurate.
B) the experiment proceeds at a slow pace to guarantee that the scientist can carefully observe all reactions and process all
experimental data.
C) two experiments are conducted, one differing from the other by only a single variable.
D) two experiments are conducted, one differing from the other by two or more variables.
E) one experiment is performed, but the scientist controls the variables.
Scenario Questions: After reading the following paragraph, answer the question(s) below.
The National Institutes of Health (NIH) set up a study to determine whether large doses of vitamin C would shorten the length of time it takes to recover from a cold. Three thousand volunteers were split into two groups. For two weeks, members of Group A took 3,000 mg of vitamin C daily. Group B received 3,000 mg of a placebo. At the end of the two-week period, the researchers inserted live cold viruses directly into the noses of all the volunteers. The volunteers in both Group A and B continued to take their daily pills. All the volunteers got colds, and there was no significant difference in the length of time the colds lasted.
1. Which was the experimental group?
A) Group A only
B) Group B only
C) all 3,000 volunteers
D) half of Group A and half of group B
E) the researchers that inserted the cold virus
2. To have confidence that the results of the experiment were valid, you'd also want to know
A) the genders of the volunteers.
B) whether any volunteers had colds at the start of the experiment.
C) whether the volunteers exercised daily.
D) whether the volunteers all worked for the same company.