Name: ______________________ Class: _________________ Date: _________
ID: A
Unit 1 Pretest
True/False
Indicate whether the statement is true or false.
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1. If a neutral atom contains 18 protons, it also contains 18 electrons.
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2. An ionic bond is formed when two atoms share electrons.
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3. Diffusion over large distances is slow and inefficient because it relies on random movement of
molecules and ions.
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4. Stem cells are only of one type: embryonic.
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5. A gamete has one-half the number of chromosomes of a regular body cell.
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6. During meiosis, chromosome number is reduced through three rounds of cell division.
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7. During meiosis I, homologus chromosome pairs are separated when the centromeres split apart.
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8. Meiosis occurs during both sexual reproduction and asexual reproduction.
Multiple Choice
Identify the choice that best completes the statement or answers the question.
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9. Which particle in the nucleus of an atom has a neutral charge?
a. carbon
c. neutron
b. electron
d. proton
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10. Which substance has at least one ionic bond?
a. CH4
c. NaCl
b. H2 O
d. O2
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11. A molecule of water (H2 O) has which bonds?
a. 1 covalent bond
c. 2 covalent bonds
b. 1 ionic bond
d. 2 ionic bonds
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12. How does an enzyme influence a biological reaction?
a. It increases the net energy difference between reactants and products.
b. It decreases the activation energy necessary to initiate the chemical change.
c. It increases the kinetic energy of reactants, thereby increasing their tendency to
d.
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collide.
It decreases the kinetic energy of reactants, enabling them to undergo chemical
change more easily.
13. A student set up four test tubes containing starch solution in which to perform starch digestion.
Supplies included amylase (enzyme that digests starch) and an incubator. In which tube listed would
starch digestion proceed most quickly?
a. Tube 1: No amylase, room temperature (25ºC)
b. Tube 2: No amylase, body temperature (37ºC)
c. Tube 3: Amylase present, room temperature (25ºC)
d. Tube 4: Amylase present, body temperature (37ºC)
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14. A hydrogen bond can form between a hydrogen atom of one molecule and which atom of another
molecule?
a. carbon
b. hydrogen
c. oxygen
d. sodium
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15. Which property is responsible for the fact that water and oil do not mix?
a. density
c. phase
b. mass
d. polarity
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16. A single carbon atom can form a maximum of how many single covalent bonds?
a. 2
c. 6
b. 4
d. 8
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17. In humans and other multicelluar organisms, which substance plays a central role as an energy source?
a. carbohydrate
c. protein
b. fat
d. water
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18. Both Schwann and Virchow developed important theories about cells in the mid 1800s. Which best
explains the reason these theories were made within a few years of each other?
a. Hooke’s Micrographia inspired both theories.
b. New microscopes provided better viewing of cells.
c. Scientists invented the microscope in the mid 1800s.
d. The electron microscope was used for the first time.
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19. Which statement is true about bacterial cells?
a. The cells are very large.
c. They are eukaryotes.
b. The cells have no nucleus.
d. They have organelles.
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20. Which substance on the plasma membrane helps identify chemical signals from outside the cell?
a. receptor proteins
c. membrane protein
b. cholesterol
d. transport protein
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21. Which organelle converts sugars into energy?
a. lysosome
c. nucleus
b. mitochondrion
d. ribosome
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22. What is a major difference between facilitated diffusion and active transport?
a. Active transport moves substances against the concentration gradient.
b. Active transport uses proteins in the process.
c. Facilitated diffusion moves molecules through the plasma membrane.
d. Facilitated diffusion requires large amounts of energy.
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23. A plant cell is placed in a hypotonic solution. What will happen to the plant cell?
a. It will swell.
c. It will stay the same.
b. It will shrink.
d. It will wilt.
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24. Algal cells are placed in an isotonic solution. Additional amounts of solutes are slowly added to the
solution. What happens to the cells?
a. They will begin to swell.
b. They will burst.
c. They will stay the same.
d. They will shrink.
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25. What types of materials are expelled from cells during exocytosis?
a. large molecules such as hormones
b. positive and negative ions
c. small molecules such as carbon dioxide
d. water and glycerol
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26. By
a.
b.
c.
d.
the end of prophase, each of the following has occurred except ____.
tighter coiling of the chromosomes
breaking down of the nuclear envelope
disappearing of the nucleolus
lining up of chromosomes in the cell
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Figure 9-2
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27. Which of the cells depicted in the line graph in Figure 9-2 are most likely cancerous?
a. A
c. C
b. B
d. D
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28. Why is the synthesis stage called this?
a. because protein synthesis is taking place
b. because DNA synthesis is taking place
c. because it combines several smaller stages into one
d. because the chromosomes come together
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29. A cell has 12 chromosomes. How many chromosomes will each daughter cell have after division?
a. 4
c. 12
b. 6
d. 24
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30. The cell cycle is regulated by
a. cyclins
b. enzymes
c. hormones
d. sugars
31. What is cancer caused by?
a. cell-membrane damage
b. metabolic poisoning
c. mutation
d. immune-system damage
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32. If you were studying the causes of cancer, which topic might interest you?
a. cyclin-dependent kinases
c. spindle-fiber structure
b. centromere structure
d. cell membranes
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Figure 9-4
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33. Figure 9-4 illustrates which stage of mitosis?
a. anaphase
c. prophase
b. metaphase
d. telophase
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34. How is the alignment of chromosomes, shown in Figure 9-4, on the equatorial plate of the cell
maintained?
a. They are always located there, since that is where the nucleus was.
b. Tension between opposite spindle fibers pulls them there.
c. The pressure of the cytoplasm moves them there.
d. The chromosomes are attracted to each other and meet there.
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35. Which of the phases of mitosis has the shortest duration?
a. anaphase
c. metaphase
b. cytokinesis
d. prophase
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36. The typical growth period of a cell occurs during which stage of the cell cycle?
a. Gap 1
c. synthesis
b. Gap 2
d. mitosis
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37. Colchicine is a chemical that when applied to a cell during mitosis can be used to “freeze” cells in
metaphase by preventing the chromosomes from moving away from the metaphase plate. What part
of the cell does colchicine most likely affect?
a. chromosome structure
c. nuclear membrane
b. spindle fibers
d. cell membrane
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38. A stem cell has potential medical uses because it
a. undergoes mitosis.
b. is not specialized in structure and function.
c. is similar to a cancer cell, providing a study system.
d. undergoes apoptosis.
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39. During which phase of meiosis do homologous pairs of chromosomes line up next to one another along
the equator?
a. anaphase I
b. metaphase I
c. prophase II
d. metaphase II
Completion
Complete each statement.
40. Elements are pure substances made up of only one kind of ____________________.
41. Molecules that have an unequal distribution of charges are called ____________________ molecules.
42. The electrostatic attraction between adjacent water molecules is called a(n) ____________________
bond.
43. Interphase is divided into three stages: G1, ____________________, and G2.
44. Once the cell cycle begins, there are built-in ____________________ that can stop it at any time.
Short Answer
45. List and describe the parts of the cell theory.
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