Chapter 5: Cells-The Working Units of Life

cell

1. The fundamental unit of life is the _______.

nuclear pores

10. RNA is able to carry information for protein synthesis from the DNA in the nucleus to the ribosomes in the cytoplasm by passing through small perforations in the nuclear membrane called _______.

smooth ER

13. Steroids, fatty acids, and phospholipids are synthesized in the _______.

c. RNA and proteins.

14. Ribosomes are made up of a. DNA and RNA. b. DNA and proteins. c. RNA and proteins. d. proteins. e. DNA.

d. stroma.

51. The DNA of a chloroplast is located in the a. intermembrane space. b. matrix. c. cristae. d. stroma. e. granum.

increase

3. When you cut an orange in half, you _______ the surface area-to-volume ratio.

b. DNA and protein.

33. Chromatin is a series of entangled threads composed of a. microtubules. b. DNA and protein. c. fibrous proteins. d. cytoskeleton. e. membranes.

a. nuclear lamina.

35. A component of the nucleus that may be involved in the aging process is the a. nuclear lamina. b. nuclear pore. c. nuclear matrix. d. nucleoplasm. e. nuclear envelope.

b. glandular

43. Cells that synthesize a large amount of protein, such as _______ cells, are packed with rough endoplasmic reticulum. a. liver b. glandular c. red blood d. skin e. brain

d. SER.

44. Cells that perform little protein synthesis but are involved with protein modification typically have large numbers or amounts of a. RER. b. mitochondria. c. ribosomes. d. SER. e. lysosomes.

a. cellular respiration.

49. In the mitochondria, "food" molecules are converted to ATP by a process known as a. cellular respiration. b. metabolism. c. diffusion. d. metabolic processing. e. catabolism.

c. explains why cells are small.

5. The surface area-to-volume ratio of a cell a. can be increased by increasing the volume of the cell. b. can be decreased by decreasing the surface area. c. explains why cells are small. d. is of little significance to maintaining cell homeostasis. e. None of the above

b. is used to make proteins needed for cellular respiration.

50. The DNA of mitochondria a. is needed to hydrolyze monomers. b. is used to make proteins needed for cellular respiration. c. directs photosynthesis. d. controls the cell's activities. e. synthesizes polysaccharides for the plant cell wall.

e. chromoplasts.

56. The carotenoid pigments that give ripe tomatoes their red color are contained in organelles called a. chloroplasts. b. proplastids. c. protoplasts. d. leucoplasts. e. chromoplasts.

e. Vacuole

60. Of the following plant cell structures, which is most likely to have the greatest volume? a. Glyoxysome b. Lysosome c. Chromosome d. Ribosome e. Vacuole

nucleoid

7. The DNA in a prokaryotic cell can be found in the _______ region.

b. membrane-lined channels called plasmodesmata.

74. Uniform concentrations of cytoplasmic materials in plants are maintained by a. motor proteins such as kinesin. b. membrane-lined channels called plasmodesmata. c. the semirigid cell wall. d. constantly-beating cilia. e. an internal cytoskeleton.

b. Mitochondria and chloroplasts

78. Which of the following organelles were once independent prokaryote organisms? a. Mitochondria and lysosomes b. Mitochondria and chloroplasts c. Chloroplasts and Golgi apparatus d. Golgi apparatus and ribosomes e. Ribosomes and lysosomes

d. are prokaryotes.

8. Members of the domains Bacteria and Archaea a. have nuclei. b. have chloroplasts. c. are multicellular. d. are prokaryotes. e. have flagella.

c. animal

75. The type of cell that always lacks a cell wall is the _______ cell. a. bacterial b. plant c. animal d. fungal e. prokaryotic

b. nucleus.

26. A large organelle found in eukaryotic cells that genetically controls the cell's activities is the a. chloroplast. b. nucleus. c. flagellum. d. vacuole. e. centriole.

c. Vacuole

27. You would not expect to find RNA in which of the following structures? a. Nucleus b. Mitochondrion c. Vacuole d. Ribosome e. Prokaryotic cell

d. nucleus.

28. Of the following structures of an animal cell, the one with the largest volume is the a. cilium. b. mitochondrion. c. lysosome. d. nucleus. e. ribosome.

a. glycoproteins found on the packaged proteins.

41. Proteins from the Golgi are transported to the correct location by means of a. glycoproteins found on the packaged proteins. b. the general flow of vesicles within the cell. c. the control provided by the nucleus. d. motor proteins. e. microtubules.

c. Golgi apparatus.

42. An organelle consisting of a series of flattened sacks stacked somewhat like pancakes is the a. mitochondrion. b. chloroplast. c. Golgi apparatus. d. rough endoplasmic reticulum. e. flagellum.

ER (or endoplasmic reticulum)

16. The substances that enter the Golgi come from the _______.

intermediate

21. Tough ropelike filaments that stabilize cell structure and resist tension are called _______ filaments.

b. regulates traffic into and out of the cell.

23. The membrane surrounding each organelle a. is composed of hydrophobic proteins. b. regulates traffic into and out of the cell. c. is studded with ribosomes. d. allows for interactions among molecules. e. is perforated with pores.

e. All of the above

3. What must cells do in order to survive? a. Obtain and process energy b. Convert genetic information into proteins c. Keep certain biochemical reactions separate from one another d. Both a and b e. All of the above

c. the SER.

39. Cholesterol is synthesized by a. chloroplasts. b. lysosomes. c. the SER. d. the Golgi. e. mitochondria.

e. leucoplasts.

57. Starch molecules are stored inside a. chromoplasts. b. granularplasts. c. chloroplasts. d. potatoplasts. e. leucoplasts.

c. large enough to be seen with a light microscope.

1. Most plant and animal cells are a. smaller than a chloroplast. b. smaller than most bacteria. c. large enough to be seen with a light microscope. d. smaller than small molecules. e. large enough to be seen with the unaided eye.

c. electron microscopes have more resolving power than light microscopes.

10. Ribosomes are not visible under a light microscope, but they can be seen with an electron microscope because a. electron beams have more energy than light beams. b. electron microscopes focus light with magnets. c. electron microscopes have more resolving power than light microscopes. d. electrons have such high energy that they pass through biological samples. e. living cells can be observed under the electron microscope.

nuclear lamina

11. The shape of the nucleus is maintained by a protein meshwork called the _______.

b. A nuclear envelope

11. Which of the following is not a characteristic of a prokaryotic cell? a. A plasma membrane b. A nuclear envelope c. A nucleoid d. Ribosomes e. Enzymes

NLS (or nuclear localization signal)

12. A short sequence of amino acids that determines whether a protein enters the nucleus is called the _______.

d. Ribosomes

12. Which of the following is (are) found in prokaryotic cells? a. Mitochondria b. Chloroplasts c. Nuclear membrane d. Ribosomes e. Endoplasmic reticulum

d. nucleoid region.

13. The DNA of prokaryotic cells is found in the a. plasma membrane. b. nucleus. c. ribosome. d. nucleoid region. e. mitochondria.

Golgi apparatus

14. The _______ is an organelle that serves as a sort of "post office," where some of the proteins synthesized on ribosomes and the rough ER are processed and sent to their destinations.

c. is composed largely of water.

15. The cytosol a. is a static region of the cell. b. contains DNA. c. is composed largely of water. d. supports the cell and determines its shape. e. chemically modifies proteins and other molecules.

cis

15. The side of the Golgi facing the ER is the _______ face.

a. cell wall.

16. A specialized structure found in some prokaryotes is the a. cell wall. b. ribosome. c. cytosol. d. mitochondrion. e. chloroplast.

d. pili.

17. Specialized cellular appendages of prokaryotes that help bacteria adhere to one another when they exchange genetic material are called a. the Golgi apparatus. b. cilia. c. flagella. d. pili. e. b, c, and d

mitochondrion

17. The organelle with many folds, called cristae, is the _______.

a. carry on photosynthesis.

18. In some prokaryotic organisms, the plasma membrane folds to form an internal membrane system that is able to a. carry on photosynthesis. b. engulf and phagocytize bacteria. c. synthesize proteins. d. propel the cell. e. hydrolyze carbohydrates to ATP.

photosynthesis

18. _______ is the process by which light energy is converted into chemical bonds.

a. flagellum.

19. Some bacteria are able to propel themselves through liquid by means of a structure called the a. flagellum. b. pilus. c. cytoplasm. d. cell wall. e. peptidoglycan molecule.

peroxisomes

19. Toxic peroxides that are formed unavoidably as side products of important cellular reactions are collected and neutralized in _______.

d. making it spherical.

2. The surface area-to-volume ratio of an object can be decreased by a. cutting it into smaller pieces. b. flattening it. c. stretching it. d. making it spherical. e. All of the above

cell theory

2. The three principle tenets of biology—that all organisms are composed of cells, that all cells come from preexisting cells, and that cells are the fundamental units of life—make up the unifying principle known as the _______.

b. lose some of its ability to adhere to other cells.

20. If you removed the pili from a bacterial cell, the bacterium would a. no longer be able to swim. b. lose some of its ability to adhere to other cells. c. no longer be able to regulate the movement of molecules into and out of the cell. d. dry out. e. change its shape.

Microfilaments

20. _______ are involved in cytoplasmic streaming, in the "pinching" of a cell that ultimately divides an animal cell into two daughter cells, and in the formation of pseudopodia.

e. only eukaryotes have compartmentalization, which allows for specialization.

21. Prokaryotic cells generally are smaller than eukaryotic cells because a. prokaryotes have more diverse energy sources. b. prokaryotes have a capsule that limits cell growth. c. the rigid cell wall of prokaryotes limits cell size. d. prokaryotes lack the genetic material needed for protein synthesis. e. only eukaryotes have compartmentalization, which allows for specialization.

e. All of the above

22. Biological membranes in a eukaryotic cell a. separate the cell from its environment. b. regulate what goes into and out of the cell. c. help maintain a constant internal environment. d. communicate with adjacent cells. e. All of the above

c. increase the efficiency of cellular activities.

24. The role of organelles is to a. provide structural support for the cell. b. decrease the flow of materials into and out of the cell. c. increase the efficiency of cellular activities. d. provide a means of cellular reproduction. e. regulate the flow of traffic inside the cell.

d. Both a and b

25. Which of the following statements about the nuclear envelope is true? a. It contains pores for the passage of large molecules. b. It is composed of two membranes. c. It contains ribosomes on the inner surface. d. Both a and b e. All of the above

c. genetic information is used to make proteins.

29. Ribosomes are the structures in which a. chemical energy is stored in the form of ATP. b. cell division is controlled. c. genetic information is used to make proteins. d. sunlight energy is converted into chemical energy. e. new organelles are made.

e. the Golgi apparatus.

30. Ribosomes are not found in a. mitochondria. b. chloroplasts. c. the rough endoplasmic reticulum. d. prokaryotic cells. e. the Golgi apparatus.

d. Both a and b

31. What is the difference between "free" and "attached" ribosomes? a. Free ribosomes are in the cytoplasm, whereas attached ribosomes are anchored to the endoplasmic reticulum. b. Free ribosomes produce proteins in the cytosol, whereas attached ribosomes produce proteins that are inserted into the ER. c. Free ribosomes produce proteins that are exported from the cell, whereas attached ribosomes make proteins for mitochondria and chloroplasts. d. Both a and b e. Both a and c

b. only animal cells contain centrioles.

32. One difference between plant and animal cells is that a. only animal cells have mitochondria. b. only animal cells contain centrioles. c. plant cells have a cell wall, whereas animal cells have a plasma membrane. d. plant cells lack a cytoskeleton. e. only plant cells have peroxisomes.

d. regulate movement of materials across the nuclear membrane.

34. The function of the nuclear pores is to a. synthesize and repair DNA, the unit of genetic information. b. assemble ribosomes from raw materials that are synthesized in the nucleus. c. communicate with components of the endomembrane system. d. regulate movement of materials across the nuclear membrane. e. support the nuclear envelope.

a. nucleus.

36. The membranes of the endoplasmic reticulum are continuous with the membranes of the a. nucleus. b. Golgi apparatus. c. nucleolus. d. plasma membrane. e. mitochondria.

e. Plastids

37. Which of the following is not a component of the endomembrane system? a. Rough endoplasmic reticulum b. Smooth endoplasmic reticulum c. Golgi apparatus d. Lysosomes e. Plastids

c. has ribosomes attached to it.

38. The rough ER is the portion of the ER that a. lacks ribosomes. b. is the oldest and was once the smooth ER. c. has ribosomes attached to it. d. is connected to the Golgi apparatus. e. is the site of steroid synthesis.

d. The ratio decreases as the cube becomes larger.

4. How does the surface area-to-volume ratio of a 1-mm cube compare to the surface area-to-volume ratio of a 3-mm cube? a. The 3-mm cube has a higher ratio. b. The ratio increases as the cube becomes larger. c. Increasing the volume increases the ratio. d. The ratio decreases as the cube becomes larger. e. The ratio does not change.

homeostasis

4. The ability of living organisms to maintain a constant internal environment is known as _______.

d. ribosomes on the rough endoplasmic reticulum.

40. Proteins that are transported in vesicles are made by a. the Golgi apparatus. b. ribosomes within the mitochondrion. c. the smooth endoplasmic reticulum. d. ribosomes on the rough endoplasmic reticulum. e. ribosomes within chloroplasts.

d. is a primary lysosome that has fused with a phagosome.

45. A secondary lysosome is a lysosome that a. provides a backup to the primary lysosomes. b. is smaller than a primary lysosome. c. will become a primary lysosome when it fuses with a phagosome. d. is a primary lysosome that has fused with a phagosome. e. has exocytosed.

e. digestive enzymes.

46. Lysosomes are important to eukaryotic cells because they contain a. photosynthetic pigments. b. starch molecules for energy storage. c. their own DNA molecules. d. the cells' waste materials. e. digestive enzymes.

a. They are the sites where autophagy occurs.

47. Which of the following statements about lysosomes is true? a. They are the sites where autophagy occurs. b. They provide turgor in plant cells. c. They may contain anthocyanins that aid in pollination. d. They are found only in plants. e. They may have arisen through endosymbiosis.

c. increase the surface area for the exchange of substances across the membrane.

48. The folds of the inner mitochondrial membrane a. increase the volume of the mitochondrial matrix. b. create membrane-enclosed compartments within the mitochondrion. c. increase the surface area for the exchange of substances across the membrane. d. anchor the mitochondrial DNA. e. have no known purpose.

electromagnets

5. The light microscope has glass lenses that focus visible light for imaging, whereas the electron microscope has _______ that focus electrons for imaging.

a. grana and thylakoids.

52. Components of chloroplasts include a. grana and thylakoids. b. chromatin and nucleoplasm. c. cristae and matrix. d. a trans region and a cis region. e. lysosomes and phagosomes.

d. Plastids

53. Which type of organelle is found in plants but not in animals? a. Ribosomes b. Mitochondria c. Nuclei d. Plastids e. None of the above

d. sunlight energy is converted into chemical energy.

54. Chloroplasts are the structures in which a. chemical energy is stored in the form of ATP. b. cell division is controlled. c. genetic information is used to make proteins. d. sunlight energy is converted into chemical energy. e. new organelles are made.

e. plastid.

55. Chloroplasts are a kind of a. leucoplast. b. endoplasmic reticulum. c. chromoplast. d. Golgi apparatus. e. plastid.

e. All of the above

58. Which of the following is a function of a plant cell vacuole? a. Storage of toxic by-products and wastes b. Support for the cell c. Containment of animal-attracting pigments that aid in pollination d. Hydrolysis of seed proteins into plant embryo food e. All of the above

d. Glyoxysome

59. Which of the following organelles is found only in plant cells? a. Cilium b. Nucleus c. Mitochondrion d. Glyoxysome e. Peroxisome

a. regulate which materials can cross the membrane.

6. A general function of all cellular membranes is to a. regulate which materials can cross the membrane. b. support the cell and determine its shape. c. produce energy for the cell. d. produce proteins for the cell. e. move the cell.

prokaryotes

6. Archaea and Bacteria do not typically have membrane-enclosed internal compartments; therefore, they are known as _______.

b. cytoskeleton.

61. The overall shape of a cell is determined by its a. cell membrane. b. cytoskeleton. c. nucleus. d. cytosol. e. endoplasmic reticulum

e. Helping to anchor the cell in place

62. Which of the following is not a function of vacuoles? a. Contributing to plant survival b. Helping plants maintain turgor pressure c. Containing pigments that aid in pollination d. Aiding in plant embryo development e. Helping to anchor the cell in place

b. actin.

63. Microvilli are created by projections of a. microtubules. b. actin. c. myosin. d. intermediate filaments. e. None of the above

a. α- and β-tubulin.

64. Microtubules are composed of monomers of a. α- and β-tubulin. b. δ- and λ-actin. c. ρ- and σ-myosin. d. κ tubules. e. κ actinomin.

e. Intermediate filaments

65. Which of the following structures is (are) involved with maintaining the position of the organelles within a cell? a. Golgi apparatus b. Endoplasmic reticulum c. Mitochondria d. Microfilaments e. Intermediate filaments

e. keratin.

66. Hair and intermediate filaments are composed of a. microtubules. b. microfilaments. c. collagen. d. hydroxyapatite. e. keratin.

b. tubulin, and they are essential in chromosome distribution during mitosis.

67. Microtubules are made of a. actin, and they function in locomotion. b. tubulin, and they are essential in chromosome distribution during mitosis. c. tubulin, and they are found in microvilli. d. actin, and they function to change cell shape. e. polysaccharides, and they function in locomotion.

d. flagellum.

68. An organelle with an internal cross-section showing a characteristic "9 + 2" morphology is the a. mitochondrion. b. vacuole. c. Golgi apparatus. d. flagellum. e. cytoskeleton.

a. are shorter and more numerous than flagella.

69. Cilia a. are shorter and more numerous than flagella. b. are composed of microfilaments. c. are composed of intermediate filaments. d. propel ribosomes through the cytoplasm. e. are needed for plasmodesmata to function.

a. A prokaryotic cell does not have a nucleus, whereas a eukaryotic cell does.

7. What is the major distinction between a prokaryotic and a eukaryotic cell? a. A prokaryotic cell does not have a nucleus, whereas a eukaryotic cell does. b. A prokaryotic cell does not have DNA, whereas a eukaryotic cell does. c. A prokaryotic cell is smaller than a eukaryotic cell. d. Prokaryotic cells have not prospered, whereas eukaryotic cells are evolutionary "successes." e. A prokaryotic cell cannot obtain energy from its environment.

e. microvilli.

70. The surface area of the small intestine is greatly increased by a. microtubules. b. pili. c. thylakoid membranes. d. myosin. e. microvilli.

b. Basal body

71. Which of the following organelles is found at the base of every eukaryotic cilium and flagellum? a. Centriole b. Basal body c. Nucleolus d. Flagellum e. Microvillus

a. basal bodies

72. The cellular structures that are almost identical to centrioles are the a. basal bodies. b. microbodies. c. chromoplasts. d. microfilaments. e. centromeres.

c. cell wall.

73. The semirigid structure that supports the plant cell and determines its shape is the a. capsule. b. flagellum. c. cell wall. d. cytosol. e. cytoplasm.

d. helps orient cell movements during embryonic development.

76. The extracellular matrix of animal cells a. is composed of cellulose. b. contains plasmodesmata. c. limits the cell volume by remaining rigid. d. helps orient cell movements during embryonic development. e. acts as a barrier to disease-causing fungi.

d. originated from endosymbiotic relationships.

77. Some organelles in eukaryotic cells are thought to have a. originated from extracellular symbiotic relationships. b. their own endoplasmic reticulum. c. their own mitochondria. d. originated from endosymbiotic relationships. e. the ability to live free from the host cell.

b. Mitochondria and chloroplasts cannot be grown in culture, free of a host cell.

79. Which of the following is not an argument for the endosymbiotic theory? a. Mitochondria and chloroplasts are about the same size as prokaryotic cells. b. Mitochondria and chloroplasts cannot be grown in culture, free of a host cell. c. Mitochondria and chloroplasts have DNA and ribosomes. d. Mitochondrial ribosomes synthesize proteins similar to those synthesized by bacterial ribosomes. e. All of the above are arguments for the endosymbiotic theory.

capsule

8. Some bacteria are not detected by the human immune system because they possess an outer layer of slime known as a _______.

a. nucleus; membrane-bound

9. A prokaryotic cell does not have a _______ or _______. a. nucleus; membrane-bound organelles b. nucleus; DNA c. nucleus; ribosomes d. nucleus; membranes e. cell wall; membranes

organelles

9. Membrane-bound compartments with distinctive shapes and functions are termed _______.