1. Which of these is reflective of the hierarchical organization of life from most to least inclusive?
a. Kingdom, order, family, phylum, class, genus, species
b. Phylum, class, order, kingdom, family, genus, species
c. Kingdom, phylum, class, order, family, genus, species
d. genus, species, kingdom, phylum, class, order, family
e. class, order, kingdom, phylum, family, genus, species

Answer: c

2. Evolution is biology's core theme that ties together all the other themes.
This is because evolution
a. Explains the unity and diversity of life
b. Explains how organisms become adapted to their environment through the differential reproductive success of varying individuals
c. Explains why distantly related organism sometimes resemble each other
d. Explains why some organism have traits in common
e. All of the above

Answer: e

3. A controlled experiment is one in which
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. There are at least two groups, one of which does not receive the experimental treatment
d. There are at least two groups, one differing from the other by two or more variables
e. There is one group for which the scientist controls all variables

Answer: c

4. About 25 of the 92 occurring elements are known to be essential to life. Which four of these 25 elements make up approximately 96% of living matter?
a. carbon, sodium, chlorine, nitrogen
b. carbon, sulfur, phosphorus, hydrogen
c. oxygen, hydrogen, calcium, sodium
d. carbon, hydrogen, nitrogen, oxygen
e. carbon, oxygen, sulfur, calcium

Answer: d

5. Which drawing below depicts the electron configuration of oxygen (¹⁶ ₈O)
a. A
b. B
c. C
d. D
e. E

Answer: c

6. What does the reactivity of an atom depend on?
a. Number of valence shells in the atom
b. Number of orbitals found in the atom
c. Number of electrons in each orbital in the atom
d. Presence of unpaired electrons in the outer valance shell of the atom
e. Presence of hybridized orbitals in the atom

Answer: d

7. A covalent chemical bonds is one in which
a. Electrons are removed from one atom and transferred to another atom so that the two atoms become oppositely charged
b. Protons and neutrons are shared by two atoms so as to satisfy the requirements of both atoms
c. Outer-shell electrons of two atoms are shared so as to satisfactorily fill the outer electron shell of both atoms
d. Outer-shell electrons of an atom are transferred to the inner electron shells of another atom
e. The inner-shell electrons of one atom are transferred to the outer-shell of another atom.

Answer: c

8. What results from an unequal sharing of electrons between atoms?
a. A nonpolar covalent bond
b. A polar covalent bond
c. An ionic bond
d. A hydrogen bond
e. A hydrophobic interaction

Answer: b

9. Which bonds must be broken for water to vaporize?
a. Ionic bonds
b. Nonpolar covalent bonds
c. Polar covalent bonds
d. Hydrogen bonds
e. Covalent bonds

Answer: d

10. One mole (mol) of a substance is
a. 6.02 x 10²³ molecules of the substances
b. 1g of the substance dissolved in n 1 L of solution
c. The largest amount of the substance that can be dissolved in 1 of solution
d. The molecular mass of the substance expressed in grams.
e. A and D only

Answer: e

11. One liter of a solution of pH has how many more hydrogen ions (H+) than 1 L of a solution of pH 6?
a. 4 times more
b. 400 times more
c. 4,000 times more
d. 10,000 times more
e. 100,000 times more

Answer: d

12. Observe the structure of glucose and fructose in the Figure above
These two molecules are
a. Geometric isomers
b. Enantiomers
c. Geometric isomers
d. Structural isomers
e. Nonisotopic isomers

Answer: d

13. Polymers of polysaccharides, fats and proteins are all synthesized from monomers by which process?
a. Connecting monosaccharides together (condensation reactions)
b. The addition of water to each monomer (hydrolysis)
c. The removal of water (dehydration reactions)
d. Ionic bonding of the monomers
e. The formation of disulfide between monomers

Answer: c

14. If 128 molecules of the general type shown in the figure above were covalently joined together in sequence, the single molecule that would result would be a
a. Polysaccharide
b. Polypeptide
c. Polyunsaturated lipid
d. Monosaccharide
e. Disaccharide

Answer: a

15. The 20 different amino acids found in polypeptides exhibit different chemical and physical properties because of different
a. Carboxyl groups attached to an alpha (α) carbon
b. Amino groups attached to an alpha (α) carbon
c. Side chains (R groups)
d. Alpha (α) carbons
e. Asymmetric carbons

Answer: c

16. The tertiary structure of a protein is the
a. Bonding together of several polypeptide chains by weak bonds
b. Order in which amino acids are joined in a polypeptide chain
c. Unique three-dimensional shape of the fully folded polypeptide
d. Organization of a polypeptide chain into a a-helix or B-pleated sheet

Answer: c

17. What would be an unexpected consequence of changing one amino acid in a protein consisting of 325 amino acids?
a. The primary structure of the protein would be changed
b. The tertiary structure of the protein might be changed
c. The biological activity or function of the protein might be altered
d. Only A and C are correct
e. A, B and C are correct

Answer: e

18. Which of the following best describes the flow of information in eukaryotic cells?
a. DNA → RNA → Proteins
b. RNA → Proteins → DNA
c. Proteins → DNA → RNA
d. RNA → DNA → Proteins
e. DNA → Proteins → RNA

Answer: a

19. All of the following nitrogenous bases are found in DNA except:
a. thymine
b. adenine
c. uracil
d. guanine
e. cytosine

Answer: c

20. Which of the following types of molecules are the major structural components of the cells membrane?
a. Phospholipids and cellulose
b. Nucleic acids and proteins
c. Phospholipids and proteins
d. Proteins and cellulose
e. Glycoproteins and cholesterol

Answer: c

21. A patient has had a serious accident and lost a lot of blood. In an attempt to replenish body fluids, distilled water, equal to the volume of blood lost is transferred directly into one of his veins. What will be the most probable result of this transfusion?
a. It will have no unfavorable effect as long as the water is free of viruses and bacteria
b. The patient's red blood cells with shrivel up because the blood fluid is hypotonic compared to the cells
c. The patient's red blood cells will swell because the blood fluid is hypotonic compared to the cells
d. The patient's red blood cells will shrivel up because the blood fluid is hypertonic compared to the cells

Answer: c

22. The movement of a substance across a biological membrane against its concentration gradient with the help of energy input is
a. Diffusion
b. Active transport
c. Osmosis
d. Facilitated diffusion
e. Exocytosis

Answer: b

23. The sodium-potassium is called an electrogenic pump because it
a. Pumps equal quantities of Na+ and K+ across the membrane
b. Pumps hydrogen ions out of cells
c. Contributes to the membrane potential
d. Ionizes sodium and potassium atoms
e. Is used to drive the transport of other molecules against a concentration gradient

Answer: c

24. Which term most precisely describes the cellular process of breaking down large molecules into smaller ones?
a. Catalysis
b. Metabolism
c. Anabolism
d. Dehydration
e. Catabolism

Answer: e

25. Living organism increase in complexity as they grow, resulting in a decrease in the entropy of an organism. How does this relate to the second law of thermodynamics?
a. Living organism do not obey the second law of thermodynamics, which states that entropy must increase with time.
b. Life obeys the second law of thermodynamics because the decrease in entropy as the organism grows is balanced by an increase in the entropy of the universe
c. Living organism do not follow the laws of thermodynamics.
d. As a consequence of growing, organism create more disorder in their environment than the decrease in entropy associated with their growth
e. Living organism are able to transform energy into entropy

Answer: d

26. Which of the following statements regarding ATP is (are) correct?
a. ATP serves as a main energy shuttle inside cells
b. ATP drives endergonic reactions in the cell by the enzymatic transfer of the phosphate group to specific reactants.
c. The regeneration of ATP from ADP and phosphate is a endergonic reaction
d. A and B only
e. A, B and C

Answer: e

27. Increasing the substrate concentration in an enzymatic reaction could overcome which of the following?
a. Denaturization of the enzyme
b. Allosteric inhibition
c. Competitive inhibition
d. Saturation of the enzyme activity
e. Insufficient cofactors

Answer: c

28. What is the term used for the metabolic pathway in which glucose (C₆O₁₂H₆) is degraded to carbon dioxide (CO₂) and water?
a. Cellular respiration
b. Glycolysis
c. Fermentation
d. Citric acid cycle
e. Oxidative phosphorylation

Answer: a

29. In addition to ATP, what are the end products of glycolysis?
a. CO₂ and H₂O
b. CO₂ and pyruvate
c. NADH and pyruvate
d. CO₂ and NADH
e. H₂O, FADH₂, and citrate

Answer: c

30. Which kind of metabolic poison would most directly interfere with glycolysis?
a. An agent that reacts with oxygen and depletes its concentration in the cell
b. An agent that binds to pyruvate and inactivates it
c. An agent that closely mimics the structure of glucose but is not metabolized
d. An agent that reacts with NADH and oxidizes it to NAD+
e. An agent that blocks the passage of electrons along the electron transport chain

Answer: c

31. The primary role of oxygen in cellular respiration is to
a. Yield energy in the form of ATP as it is passed down the respiratory chain
b. Act as an acceptor for the electrons and hydrogen
c. Combine with carbon, forming CO₂
d. Combine with lactate, forming pyruvate
e. Catalyze the reactions of glycolysis

Answer: b

32. In a plant cell, where are the ATP synthase complexes located?
a. Thylakoid membrane
b. Plasma membrane
c. Inner mitochondrial membrane
d. A and C
e. A, B, and C

Answer: d

33. Which of the following statements best represents the relationship between the light reactions and the Calvin Cycle?
a. The light reactions provide ATP and NADPH to the Calvin Cycle and the cycle returns ADP, Pi, and NADP+ to the light reactions
b. The light reactions provide ATP and NADPH to the carbon fixation step of the Calvin Cycle, and the cycle provides water and electrons to the light reactions
c. The light reactions supply the Calvin Cycle with CO2 to produce sugars and the Calvin Cycle supplies the light reactions with sugars to produce ATP
d. The light reactions provide the Calvin Cycle with oxygen for electron flow, and the calvin cycle provides the light reactions with water to split
e. There is no relationship between the light reactions and the Calvin cycle

Answer: a

34. From the perspective of the cell receiving the message, the three stages of cell signaling are
a. The paracrine, local, and synaptic stages
b. Signal reception, signal transduction and cellular response
c. Signal reception, nucleus disintegration, and new cell generation
d. The alpha, beta and gamma stages
e. Signal reception, cellular response and cell division

Answer: b

35. Which of the following is (are) true of ligand-gated ion channels?
a. They are important in the nervous system.
b. They lead to changes in sodium and calcium concentrations in cells
c. They open or close in response to a chemical signal
d. Only A and B are true
e. A, B and C are true

Answer: e

36. The correct sequence of steps in the M phase of the cell cycle is
a. Prophase, prometaphase, metaphase, anaphase, telophase
b. Prophase, metaphase, prometaphase, anaphase, telophase
c. Prophase, prometaphase, metaphase, anaphase, telophase, cytokinesis
d. Prophase, metaphase, anaphase, telophase, cytokinesis

Answer: c

37. Which of the following is true of the process of meiosis?
a. Two diploid cells result
b. Four diploid cells result
c. Four haploid cells result
d. Four autosomes result
e. Four chiasmata result

Answer: c

38. What was the most significant conclusion that Gregor Mendel drew from his experiments with pea plants?
a. There is considerable genetic variation in garden peas.
b. Traits are inherited in discrete units, and are not the results of “blending”
c. Recessive genes occur more frequently in the F1 than do dominant ones
d. Genes are composed of DNA
e. An organism that is homozygous for many recessive traits is at a disadvantage

Answer: b

39. Two characters that appear in a 9:3:3:1 ratio in the F2 generation should have which of the following properties?
a. Each of the characters is controlled by a single generation
b. The genes controlling the characters obey the law of independent assortment
c. Each of the genes controlling the characters has two alleles
d. Only A and C are correct
e. A, B and C are correct

Answer: b

A woman who has blood type A has a daughter who is type O positive and a son who is type B negative. Rh positive is a simple dominant trait over Rh negative.
40. Which of the following is a possible genotype for the mother?
a. IAIA
b. IBIA
c. ii
d. IAI
e. IAIB

Answer: d

41. When Thomas Hunt Morgan crossed his red-eyes F1 generation flies to each other, the F2 generation included both red-and white-eyed flies. Remarkably, all the white-eyed flies were male. What was the explanation for this result?
a. The involved gene was on the X chromosome
b. The involved gene was on the Y chromosome.
c. The involved gene was on an autosome
d. Other male-specific factors include eye color in flies
e. Other female-specific factors influence eye color in flies

Answer: a

42. How could one explain a test-cross involving F1 dihybrid flies in which more parental-type offspring that recombinant-type offspring are produced?
a. The two genes are linked
b. The two genes are unlinked
c. Recombination did not occur in the cell during meiosis
d. The test-cross was improperly performed
e. Both the characters are controlled by more than one gene.

Answer: a

43. Which of the following statements does not apply to the Watson and Crick model of DNA?
a. The two strands of the DNA form a double helix
b. The distance between the strands of the helix is uniform
c. The framework of the helix consists of sugar-phospate units of the nucleotides
d. The two strands of the helix are held together by covalent bonds
e. The purines form hydrogen bonds with pyrimidines

Answer: d

44. The leading and the lagging strands differ in that
a. The leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction
b. The leading strand is synthesized by adding nucleotides to the 3' end of the growing strand, and the lagging strand is synthesized by adding nucleotides to the 5' end.
c. The leading strand is synthesized continuously, whereas the lagging strand is synthesized in short fragments that are ultimately stitched together.
d. Both A and B
e. Both A and C

Answer: a

45. A possible sequence of nucleotides in the template strand DNA that would code for the polypeptide sequence phe-leu-ile-val would be
a. 5' TTG-CTA-CAG-TAG 3'
b. 3' AAC-GAC-GUC-AUA 5'
c. 5' AUG-CTG-CAG-TAT 3'
d. 3' AAA-AAT-ATA-ACA 5'
e. 3' AAA-GAA-TAA-CAA 5'

Answer: e

46. RNA polymerase and DNA polymerase differ in that
a. RNA polymerase uses RNA as a template and DNA polymerase uses a DNA template
b. RNA polymerase binds to single-stranded DNA and DNA polymerase binds to double-stranded DNA
c. RNA polymerase is much more accurate than DNA polymerase
d. RNA polymerase can initiate RNA synthesis but DNA polymerase requires a primer to initiate DNA synthesis.
e. RNA polymerase does not need to separate the two strands of DNA in order to synthesize an RNA copy, whereas DNA polymerase must unwind the double helix before it can replicate the DNA.

Answer: d

47. A frameshift mutation could result from
a. A base insertion only
b. A base deletion only
c. A base substitution only
d. Deletion of three consecutive bases
e. Either an insertion or a deletion of a base

Answer: b

48. What is the function of reverse transcriptase in retroviruses?
a. It hydrolyzes the host cell's DNA
b. It uses viral RNA as a template for DNA synthesis
c. It converts host cell RNA into viral DNA
d. It translates viral RNA into proteins
e. It uses viral RNA as a template for making complementary RNA strands.

Answer: b

49. What are prions?
a. Misfolded versions of normal brain protein
b. Tiny molecules of RNA that infect plants
c. Viral DNA that has to attach itself to the host genome
d. Viruses that invade bacteria
e. A mobile segment of DNA

Answer: a

50.What does the operon model attempt to explain?
a. The coordinated control of gene expression in bacteria
b. Bacterial resistance to antibiotics
c. How genes move between homologous regions of DNA
d. The mechanism of viral attachment to a host cell
e. Horizontal transmission of plant viruses

Answer: a

51. Which two functional groups are always found in amino acids?
a. hydroxyl and aldehyde
b. ketone and aldehyde
c. carboxyl and amino
d. carbonyl and carboxyl

Answer: c

52. In animal cells, hydrolytic enzymes are packaged to prevent general destruction of cellular components. Which of the following organelles function in this?
a. peroxisome
b. chloroplast
c. lysosome
d. central vacuole
e. glyoxysome

Answer: c

53. A cell has the following molecules and organelles enzymes: DNA, ribosomes, plasma membrane, and mitochondria. This could be
a. a bacterial cell
b. a plant or an animal cell
c. an animal cell, but not a plant cell
d. a plant cell, but not an animal cell
e. a cell from any kind of organism

Answer: b

54. Plasmodesmata in plant cells are most similar in function to which of the following structures in animal cells?
a. gap junctions
b. peroxisomes
c. tight junctions
d. extracellular matrix
e. desmosomes

Answer: a

55. Which of the following statements concerning prokaryotic and eukaryotic cells is not correct?
a. DNA or deoxyrinonucleic acid, is present in both prokayotic cells and eukaryotic cells
b. Prokaryotic cells contain small membrane-enclosed organelles
c. Eukaryotic cells contain a membrane-bound nucleus
d. Prokaryotic cells lack a membrane-bound nucleus
e. DNA or deoxyribonucleic acid is present in the nucleus of eukaryotic cells

Answer: b

56. Celery stalks that are immersed in fresh water for several hours become stiff and hard. Similar stalks left in a salt solution become limp and soft. From this we can deduce that the cells of the celery stalks are
a. hypertonic to both fresh water and salt solution
b. hypotonic to both fresh water ans the salt solution
c. hypertonic to fresh water but hypotonic to the salt solution
d. hypotonic to fresh water but hypertonic to the salt solution
e. isotonic with fresh water but hypotonic to the salt solution

Answer: c

57. The active site of an enzyme is the region that
a. actively prevents changes in substrate concentration
b. binds to products of the catalytic reaction
c. is inhibited by the presence of a coenzyme or a cofactor
d. binds allosteric regulators of the enzyme
e. is involved in the catalytic reaction of the enzyme

Answer: e

58. When you have a severe fever, what may be a grave consequence if it is not controlled?
a. Denaturation of the body's enzymes
b. removal of amino groups from your proteins
c. destruction of your enzymes' primary structure
d. binding of enzymes to inappropriate substrates
e. removal of the amino acids in enzymes active sites

Answer: a

59. Where are the proteins of the electron transport chain located?
a. Mitochondrial intermembrane space
b. mitochondrial outermembrane
c. mitochondrial matrix
d. cytoplasm
e. mitochondrial inner membrane

Answer: e

60. Inside an active mitochondrion, most electrons follow which pathway?
a. citric acid cycle → FADH₂ → electron transport chain → ATP
b. citric acid cycle → NADH → electron transport chain → oxygen
c. electron transport chain → citric acid cycle → ATP → oxygen
d. pyruvate → citric acid cycle → ATP → NADH → oxygen
e. glycolysis → NADH → oxidative phosphorylation → ATP → oxygen

Answer: b

61. Which of the following occurs in the cytoplasm of an eukaryotic cell?
a. Glycolysis and fermentation
b. citric acid cycle
c. oxidative phosphorilation
d. oxidation of pyruvate to acetyl CoA
e. fermentation and chemiosmosis

Answer: a