Science 10 Final Review
UNIT A: ENERGY AND MATTER IN CHEMICAL CHANGE
1.The WHMIS symbol at right represents a) corrosive material
b) oxidizing material
c) a material with toxic effects d) dangerously reactive material
2. What part of the body is the most easily damaged by contact with a corrosive material? a) the skin on the lips
b) the cornea of the eye c) the skin on the hands d) the skin on the tongue
3. Which of the following is a physical change? a) boiling water
b) frying an egg
c) fermenting an apple
d) using yeast to cause dough to rise
4. Salting is a food preservation technique that is actually a method of a) drying
b) freezing c) sterilizing d) fermenting
5. Annealing is a heating process used to a) smelt iron
b) smelt copper c) make metal softer d) make metal less brittle
6. Tin ores were smelted together with copper ores in order to produce a) gold
b) bronze c) very pure tin d) very pure copper
7. Antoine Lavoisier proposed the law of conservation of mass after a) discovering the atom
b) experiments he did in combining elements c) proposing that an atom is an indivisible particle
8. J. J. Thomson experimented with beams of particles produced in a vacuum tube. By testing many elements he showed that they all produced the same type of beam. This suggested that a) all elements are made of atoms
b) atoms of different elements have different properties
c) the centre of an atom has a small positively charged nucleus
d) atoms of different elements contain smaller particles that are identical
9. Ernest Rutherford fired tiny positive particles at a thin sheet of gold foil. Most of these particles passed through the foil, but some bounced back at sharp angles. From a study of these observations he concluded that
a) electrons are negatively charged b) neutrons possess no electric charge
c) most of the mass of an atom is in one small region within the atom
d) most of the negative charge of an atom is in one small region within the atom
10. The modern model of the atom comes from the theory of quantum mechanics. In this model, an electron is described as
a) a cloud of negative charge
b) a tiny negative particle moving very quickly c) moving like a propeller spinning very quickly d) orbiting the nucleus like a planet orbiting the Sun
11. Neils Bohr studied the light released from hydrogen atoms when they are made to glow in a tube. Light is emitted from the hydrogen atoms in very specific colours. How are these colours related to the energy levels of electrons within atoms? (2 marks)
12. The periodic table organizes all the elements according to
a) date of discovery b) physical properties c) chemical properties d) chemical importance
13. Which of the following pieces of information is not shown on the periodic table? a) the mass number
b) the element name c) the atomic number d) the element symbol
14. Which of the following applies to metallic elements when they form positive ions? a) they lose electrons and become anions
b) they lose electrons and become cations c) they gain electrons and become anions d) they gain electrons and become cations
15. An element’s reactivity is related to
a) the number of neutrons it has in its nucleus b) the number of electrons it has in its nucleus
16. The IUPAC name for PbO2 is
a) lead oxide b) lead dioxide c) lead(II) oxide d) lead(IV) oxide
17. The IUPAC name for CH4 is
a) methane b) ammonia c) natural gas
d) carbon tetrahydride
18. Which of the following is an acid? a) H 2O(l)
b) NaOH(aq)
c) H2SO3(aq)
d) Na2SO3(aq)
19. Sometimes when ionic solutions are mixed, they form a precipitate. A precipitate is a) an electrolyte
b) a mixture of dissolved ions
c) a solid substance that forms when two liquids are mixed d) an aqueous substance that forms when two liquids are mixed
20. An acid has the following properties:
a) tastes sour and has no reaction with Mg b) tastes bitter and has no reaction with Mg
c) tastes sour and reacts with Mg to produce bubbles d) tastes bitter and reacts with Mg to produce bubbles
21. Which of the following are typical of a solution having a pH of 12? a) litmus is red; solution conducts electricity
b) litmus is blue; solution conducts electricity c) litmus is red; solution does not conduct electricity d) litmus is blue; solution does not conduct electricity
Part B: Written Response (10 marks)
Write the formula or name of the compounds in questions 11 to 16. (6 marks)
22. sodium sulfide
23. iron(III) nitrate
24. dinitrogen trioxide
25. Al2N3(s)
26. P4O10(s)
27. (NH4)2CrO4(s)
29. The combustion of coal is a chemical reaction used in the production of electricity. This reaction
a) absorbs energy and is exothermic b) releases energy and is exothermic c) absorbs energy and is endothermic d) releases energy and is endothermic
30. From the law of conservation of mass it can be concluded that a) all reactions involve the flow of energy
b) all reactions are accompanied by one or more phase changes
c) the total number of atoms involved in a chemical reaction remains constant
d) all reactions involve the production of new substances with their own characteristic properties
31.Chemical substances written to the right of the arrow in an equation are called a) products
b) reactants c) subscripts d) coefficients
32. Which set of coefficients correctly balances the following reaction? __ S8(s) + __ P4(s) __ P4S3(s)
a) 8, 3, 8 b) 3, 8, 8 c) 6, 8, 4 d) 1, 1, 1
33. What is the missing coefficient in the equation? C3H8(g) + ? O2(g) 3 CO2(g) + 4H2O(g)
a) 2 b) 5 c) 6 d) 10
34. An equation for a double replacement reaction is a) Fe(s) + CuSO4(aq) FeSO4(aq) + Cu(s)
b) 2 K(s) + 2 H2O(l) 2 KOH(aq) + H2(aq)
c) C3H8(g) + 5 O2(g) 3 CO2 (g) + 4 H2O(l)
d) (NH4)2CO3(aq) + Ca(OH)2(aq) 2 NH4OH(aq) + CaCO3(s)
35. The products of the single replacement reaction between AlBr3(aq) and Cl2(g) are
a) AlCl2(aq) and Br3(l)
b) AlCl3(aq) and Br2(l)
c) Br3Cl2(aq) and Al(s)
36. What is the mass of 2.00 moles of silver? a) 2.00 g
b) 109 g c) 216 g
d) 6.02 x 1023 g
Balance each equation in the next three questions. (1 mark each) 37. ____ AlCl3(s) ____ Al(s) + ____ Cl2(g)
38. ____ Mg(s) + ____ H3PO4(aq) ____ H2(g) + ____ Mg3(PO4)2(s)
39. ____ Na2CO3(aq) + ___ H3PO4(aq) ___ Na3PO4(aq) + ___ H2O(l) + ___ CO2(g)
For the next three questions: predict the formulas of the products for each reaction and WRITE them in the spaces below. Do NOT balance the equations. State the FULL name of the reaction type for each reaction. (2 marks each)
40. C18H38(s) + O2(g)
Type of reaction: _________________________________ 41. FeBr3(aq) + Pb(HCO3)2(aq)
Type of reaction: _________________________________ 42. N2O(g)
Type of reaction: _________________________________
43. When solid lithium metal is exposed to pure nitrogen gas, a rapid reaction occurs. The only product of the reaction is a solid white powder. Write the balanced equation for the reaction. (2 marks)
44. How many moles of water are in 72.08 g of H2O(l)? (1 mark)
UNIT B: ENERGY FLOW IN TECHNOLOGICAL SYSTEMS
Use the following information to answer the next two questions:
A nervous papa bear is expecting the birth of his first baby cub. He paces 10 m north in 5.0 s, then 16 m south in 5.0 s, and then 14 m north in 4.0 s.
45. The average speed of the bear is:
a) 0.57 m/s b) 1.1 m/s c) 2.9 m/s d) 4.0 m/s
46. The average velocity of the bear is:
47. Another nervous papa bear paces at 1.0 m/s north for 3.0 s, then at 1.6 m/s south for 5.0 s, and then at 1.4 m/s north for 4.0 s. The average speed of this bear is:
a) 1.3 m/s b) 1.4 m/s c) 4.0 m/s d) 8.0 m/s
48. Which one of the following is true?
a) The units for acceleration are m2/s2.
b) Acceleration is a change in speed over time. c) The slope of a speed-time graph gives the velocity.
d) A positive slope on a distance-time graph means that the object is accelerating.
Use the following information to answer the next two questions
A car changes its velocity from 8.00 m/s [E] to 4.00 m/s [E] in 2.10 s.
49. The acceleration of the car is:
a) –1.90 m/s2 [E] b) 1.90 m/s2 [E] c) –5.71 m/s2 [E] d) 5.71 m/s2 [E]
50. The acceleration of the car in the example above is:
a) positive because it is speeding up in a positive direction b) negative because it is slowing down in a positive direction. c) positive because it is slowing down in a negative direction. d) negative because it is speeding up in a negative direction.
51. The unit of work described in fundamental units is:
a) kg·m/s
b) kg·m/s2
c) kg·m2/s d) kg·m2/s2
52. A student pushes a box a horizontal distance of 8.70 m with a horizontal force of 55.0 N. The work done by the student in pushing the box is:
Use the following information about the development of the concept of energy to answer the next two questions.
The development of the concept of energy from the 1600s to the 1850s involved the following scientists:
I Liebniz II Rumford III Black IV Joule
53. Which of the scientists listed above performed experiments to prove a connection between heat and mechanical energy?
a) I only b) II and III c) II and IV d) III and IV
54. Which of the scientists listed above suggested that heat was a fluid called “caloric” fluid that flowed from hot to cold objects?
a) I b) II c) III d) IV
Use the following information to answer the next three questions.
On a camping trip, the following scenario occurs:
I A camper rubs a match on a gritty surface igniting a match.
II The match is then used to ignite a pile of wood kindling, creating a bonfire.
III While standing by the bonfire, the camper senses that the part of his body facing the fire is warm while his backside remains cool.
IV Another group of campers across the lake spots the bonfire.
55. Which of the above describes a conversion of mechanical energy to heat?
a) I b) II c) III d) IV
56. Which of the above describes a conversion of chemical energy to heat?
57. Which of the above describes a conversion of heat to radiant energy?
a) I b) II c) III d) IV
58. Which of the following is not a result of an energy transfer or transformation?
a) An object undergoes a change in motion. b) An object undergoes a change in temperature. c) An object undergoes a change in shape or position. d) An object undergoes a change in status or significance.
59. Technologically “useful” energy refers to:
a) energy needed to do work b) useful thermal energy input c) total mechanical energy input
d) input energy of a cogeneration process
60. A 2.00-kg object is thrown 3.00 m/s horizontally at 1.50 m above the ground. The total mechanical energy of the ball is:
a) 9.00 J b) 20.4 J c) 29.4 J d) 38.4 J
Use the following information to answer the next two questions:
I A carpenter applies a force on the handle of a claw hammer to pull a nail from a board and the handle moves a certain distance.
II The nail comes out of the board a certain distance.
III When the carpenter then touches the nail, she senses that the nail is hot.
61. Which of the situations stated above can best be described by the first law of thermodynamics?
a) I and II b) I and III c) II and III d) III only
62. Which of the situations stated above can best be described by the second law of thermodynamics?
Use the following information to answer the next two questions:
In the 1600s, scientists and engineers discovered the following scientific phenomena or principles:
I Two teams of eight horses could not pull two hemispheres apart because of the vacuum created inside.
II Vis viva or “living force” could be kinetic or potential.
III Water increases its volume by 1300 times when heated to steam.
63. Which of the principles listed above was/were instrumental in the development of the technology of the steam engine in the 1600s?
a) I and II b) I and III c) II only d) II and III
64. Which of the principles listed above was/were instrumental in explaining the Newton’s cradle demonstration in the 1600s?
a) I and II b) I and III c) II only d) II and III
Use the following information to answer the next three questions:
The names of some of the scientists and engineers who designed the early steam engines are listed below:
I Hero II Papin III Savery IV Newcomen V Watt
65. Which of the steam engines listed above did not have a piston?
a) I and II b) I and III c) II and IV d) III and V
66. Which of the early steam engines could be considered a turbine?
67. Which of the early steam engines first used the tilting of a beam back and forth to drive a piston that could then be used to pump water?
a) II b) III c) IV d) V
Use the following information to answer the next three questions:
Examples of energy sources are: I wind
II biomass III fossil fuels IV geothermal
68. Which of the above is not a solar energy source?
a) I b) II c) III d) IV
69. Which of the above energy sources results from the Sun heating Earth’s surface?
a) I b) II c) III d) IV
70. Which of the above involve energy from photosynthesis?
a) I and III b) I and IV c) II and III d) II and IV
71. Which of the following is not a cause of the a possible global energy shortage in the future?
a) The price of fossil fuels is increasing. b) The population is growing exponentially.
c) The demand for energy in the residential sector is increasing.
d) The economies of most countries are becoming more industrialized.
72. Which of the following solutions to the energy crisis is not a band-aid solution to the energy crisis?
73. The term “cogeneration” when applied to energy and the energy crisis refers to which of the following:
a) People should live together. b) Companies should share buildings.
c) Grandparents should live with their children and grandchildren.
d) Waste energy from one process should be used as an energy source for another process.
74. The type of energy stored in the bonds of chemical compounds is:
a) elastic energy b) potential energy
c) electromagnetic energy d) gravitational potential energy
75. A girl lifts her 30-kg knapsack a vertical distance of 0.50 m. Then she carries it 10 m across the park to the water fountain. What is the value of the work done by the girl?
Use the following information to answer the next three questions:
An archer uses a force of 60.0 N to draw back the string of his bow through a distance of 0.330 m. He then fires a 300-g arrow straight up into the air.
76. What is the value of the work done by the archer?
77. What is the maximum speed of the arrow at the instant it leaves the bow?
78. What is the maximum height reached by the arrow in its flight into the air? (Record your answer to three significant digits.)
Use the following information to answer the next two questions
A worker applies a force of 550 N in sliding a block of wood 15.0 m along a surface. The work output is determined to be 5.00103 J.
79. Calculate the efficiency of the worker.
81. A student rolls a 1.25-kg ball up a 1.50 m inclined plane with a vertical height of 0.350 m, as shown below. The uniform force exerted by the student to roll the ball up the inclined plane is 4.00 N along the incline. The time
taken to roll the ball a distance of 1.50 m is 3.30 s.
a) Calculate the work input, the work output, and the percent efficiency in rolling the ball up the inclined plane.
b) Explain why there is a difference in the work input and the work output. c) Calculate the average speed of the ball up the incline.
d) Calculate the gravitational potential energy of the ball at the top of the incline.
e) Suppose the ball drops over the edge of the inclined plane. Calculate the maximum speed of the ball just before it hits the ground below.
f) Describe the assumption that was made in determining the maximum speed of the ball.
82. A battery-operated CD player is the technology example in the following questions. In your answers, make sure to communicate clearly your understanding of the scientific principles involved.
a) Identify and describe all the energy transfers and transformations occurring in the operation of the technology. Start with the initial energy source.
b) State the first law of thermodynamics. Describe one situation in the technology where this law can be applied.
c) State the second law of thermodynamics. Describe one situation in the technology where the second law can be applied.
d) Identify one place in the technology where percent efficiency of an energy transfer or transformation will be a low value.
e) Define “sustainable” and describe how the efficiency of the technology can be changed to achieve sustainability.
UNIT C: CYCLING OF MATTER IN LIVING SYSTEMS
83. The cell structure that is too small to be clearly seen under the light microscope is the a. nucleus
b. vacuole c. chloroplast d. mitochondrion
84. What was an important difference between the microscopes used by Hooke and van Leeuwenhoek?
a. Hooke’s contained an achromatic lens.
b. Van Leeuwenhoek’s produced a blurry image with a halo.
c. Hooke’s was a simple microscope and van Leeuwenhoek’s was a compound microscope. d. Van Leeuwenhoek’s produced greater magnification than compound microscopes of that
time.
85. Pasteur presented convincing experimental evidence against the theory of spontaneous generation. In Pasteur’s experiments it was observed that
a. meat open to air developed maggots.
86. The scientist or scientists who proposed that all plants and animals were composed of cells was/were
a. Pasteur b. Virchow
c. Schleiden and Brown d. Schleiden and Schwann
87. Which of the following characteristics in the light microscope is limited by the wavelength of light?
a. contrast b. magnification c. resolving power d. size of the specimen
88. One disadvantage of the transmission electron microscope is that a. The resolution is poor.
b. The specimens are non-living.
c. The area covered by the image is very large.
d. A three-dimensional picture of the cell is easily seen from thin sections. 89. The green fluorescence protein (GFP) is used to
a. map DNA.
b. diagnose cancer. c. fix the specimen.
d. attach to and view certain cell parts.
90. One technology used to determine the three-dimensional structure of molecules is a. staining.
b. confocal technology. c. X-ray crystallography.
d. scanning electron microscopy.
91. A cell is considered an open system because it exchanges a. nothing with its surroundings
b. only matter with its surroundings. c. only energy with its surroundings.
d. matter and energy with its surroundings.
92. Which statement is true?
a. The nucleus contains the DNA.
b. The cell wall is found only in animal cells.
c. The chloroplast is responsible for cellular respiration. d. The cell membrane is a rigid frame providing strength.
93. The organelle that stores nutrients, water, products of secretion, and fats is the a. vacuole.
b. lysosome. c. ribosome. d. Golgi apparatus.
94. Which statement is true about diffusion? a. It is active transport.
b. It requires no energy.
95. An egg has had the shell removed using vinegar. It is placed in a beaker of pure, distilled water. What should happen?
a. The egg will swell. b. The egg will shrink. c. The egg will lose mass.
d. The egg will remain the same.
96. The process that produces a vesicle to enclose a large particle is termed a. osmosis
b. dialysis c. exocytosis d. endocytosis
97. A starch solution is poured into a “model cell” formed by a zipper lock bag and placed upright in a beaker of water containing iodine tincture. What will happen after a time?
a. Starch is found in the beaker of water.
b. No change is observed inside or outside the model cell.
c. Iodine ions pass into the model cell and the starch changes colour.
d. Iodine ions pass into the cell, starch passes out and the solutions inside and outside the cell change colour.
98. Which of the following is an advantage of multicellular organisms over single-celled organisms?
a. Specialized cells are less efficient in performing their tasks.
b. Single-celled organisms have a high surface to volume ratio.
c. Abnormal functioning of one cell type will affect the whole organism.
d. Internal transport systems allow movement of materials and therefore increased size.
99. Groups of cells that function together are called a/an a. body.
b. organ. c. tissue. d. system.
100. Which of these is not one of the three main types of plant tissue?
a. dermal tissue b. ground tissue c. vascular tissue d. epithelial tissue
101. Which statement is true about xylem tissue?
a. It moves sugar all around the plant.
b. The mature xylem tubes contain cytoplasm.
c. It moves water and minerals up the stem to the leaves. d. It is formed from sieve tube cells that contain cytoplasm.
102. The cells responsible for cell division and growth in plants are found in the
103. Which process produces oxygen in the leaves? a. respiration
b. transpiration c. phototropism d. photosynthesis
104. Guard cells open the stomata because
a. their turgor pressure decreases. b. water enters the cell by osmosis. c. water leaves the cell by evaporation. d. a hormone causes the cells to elongate.
105. Root pressure is the result of
a. transpiration moving water into the leaves b. attraction of water molecules for each other
c. minerals in the root cells cause water to enter by osmosis d. attraction of water molecules for other types of molecules
106. What is the loss of water through stomata and lenticels called?
a. adhesion b. cohesion c. plasmolysis d. transpiration
107. How does a plant shoot produce a phototropic response?
a. Cells on the side away from the light shrink. b. Cells on the side away from the light elongate. c. Cells on the side facing toward the light shrink. d. Cells on the side facing toward the light elongate.
Section II - Numerical Response (11 marks)
108. a) A ruler is placed under the low-power objective (4×) and measures a diameter of
4.5 mm. Determine the diameter of the high-power field of view in micrometres, if the magnification of the high-power objective is 40×. (3 marks)
b) An onion cell is observed under high power. Its length is the same as the field diameter and its width is about one third of the field of view. Determine the length and width of the onion cell in micrometres. (2 marks)
109. Two cells are observed under the microscope. Cell A is shaped like a cube with each side, s,
approximately 10 µm. Cell B is shaped more like a flat rectangular prism. Its dimensions are 160 µm length, by 40 µm width, by 1.25 µm height. Which of the cells will show a faster rate of diffusion? Explain in terms of surface area and volume. Show your calculations. (6 marks)
110. Compare the surface area to volume ratio of a cube with a side length of 5.0 cm to that of
111. Place the statements in the correct order to describe the process of water movement from the roots to the leaves. (3 marks)
1. Root pressure forces water through the cells or along cell walls into the xylem.
2. Transpiration pull combined with the forces of adhesion and cohesion, draws water up the xylem vessels.
3. A high concentration of solute in the root cells causes water to enter the root hairs through the process of osmosis.
4. Evaporation through the stomata and lenticels creates tension. 5. Water in the leaves is used to manufacture sugar in photosynthesis. 6. Water moves from the xylem into the ground tissue of the leaves.
112. A student examines three leaf specimens from aquatic plants and makes the following
observations:
Leaf A: very thin leaves, no stomata, few air spaces in the spongy mesophyll, and poorly developed xylem
Leaf B: broad leaves, upper epidermis has a thick cuticle, chloroplasts, and many stomata, large air spaces in the spongy mesophyll
Leaf C: waxy cuticle on upper and lower surface, stomata on both surfaces
Decide which leaf belongs to each of the following species and explain your reasoning. Water lily, a floating aquatic plant
Cattail, an emergent aquatic plant (leaves in the air) Elodea, a submersed (underwater) aquatic plant (6 marks)
113. A student wants to study the effect of the hormone, auxin, on the stem of plants. She
mixes a specific amount of the powdered hormone, into a known quantity of petroleum jelly. As a test, to see if the mixture will have an effect, she places a small amount on one side of the stem of a Coleus plant. After two days, she notes there is observable bending of the stem at the point of application.
a) Did the stem bend toward or away from the applied auxin site? Explain.
b) She wants to test the effect of three different concentrations of auxin on the degree of bending of the stem. Design a controlled experiment she could perform. Identify variables she must control. Describe the control for the experiment.
(5 marks)
114. Describe the fluid mosaic model of the cell membrane. Include the components and their
functions. (5 marks)
115. How did Pasteur’s experiments on spontaneous generation remove all doubt, in a way that
Spallanzani’s experiment had not? (2 marks)
116. a) Describe how the water needed for photosynthesis moves from its source outside
the plant to where it is needed in the leaf cells. Include specific structures and cell types. b) Describe how the sugar produced by photosynthesis moves from the leaf to where it is
117. Describe one practical application of our understanding of semi-permeable membranes. (2 marks)
118. In the winter, salt is often spread on the roads to “melt” the ice and snow. Cars driving along the road cause slush to spray sideways. In the spring you notice that the cedar trees close to a road have brown leaves from the ground up to a height of about a metre. Propose a plausible explanation for this observation. (2 marks)
11. Electricity is used to make a hydrogen atom glow. The electricity raises electrons to higher energy levels in the atom. When the electrons move back down to lower energy levels, they release the energy, much of it in the form of visible light. 1. A
2. B 3. A 4. A 5. D 6. B 7. D 8. D 9. C 10. A
12. C 13. A 14. B 15. D 16. D 17. A 18. C 19. C 20. C 21. B
22. Na2S(s)
23. Fe(NO3) 3 (s)
24. N2O3(g)
25. aluminium nitride 26. tetraphosphorus
decaoxide 27. ammonium
chromate
28. IUPAC or the International Union of Pure and Applied Chemistry. The rules make sure that the names of chemical compounds include both the names of the elements and the ratio or amounts of the elements. These rules allow scientists to communicate clearly and precisely by providing this information about the chemicals being used.
75. 147 J 76. 19.8 J 77. 11.5 m/s 78. 6.74 m 79. 60.6% 80. 1.43104 J 45. C 46. A 47. A 48. B 49. A 50. B 51. D 52. D
53. C 54. C 55. A 56. B 57. C 58. D 59. A 60. D
61. A 62. D 63. B 64. C 65. B 66. A 67. C 68. D
69. A 70. C 71. A 72. A 73. D 74. B
43. 6 Li(s) + N2(g) 2 Li3N(s)
44. 4.000 mol of H2O(l)
40. Products: CO2(g) + H2O(g)
Type of reaction: hydrocarbon combustion
41. Products: Fe(HCO3)3(aq) + PbBr2(s)
Type of reaction: double replacement
42. Products: N2(g) + O2(g)
Type of reaction: decomposition 37. 2, 2, 3
38. 3, 2, 3, 1 39. 3, 2, 2, 3, 3 29. b
81.a) Winput = 6.00 J Woutput = 4.29 J
percent efficiency = 71.5%
b) Some energy is lost as heat from friction. c) 0.455 m/s
d) 4.29 J e) 2.62 m/s
f) All the potential energy is converted to kinetic energy.
82.a) Chemical energy in the battery is converted to electrical energy. This electrical energy is then converted to mechanical energy in the rotation of the CD, and to light in the laser that reads the CD. The information read from the CD by the light is then converted back to electrical current, which is then converted to sound.
b) Firstlaw of thermodynamics: The total energy (including heat) put into a system and its surroundings remains constant.
All the energy put into the CD player’s system is converted to useful energy output plus heat.
c) Second law of thermodynamics: Heat flows naturally from hot to cold objects and in the process can be made to do work.
The heat generated in the CD player flows from the CD to your hand, which is cooler.
d) The percent efficiency of an energy transfer would be low when electrical energy is converted to mechanical energy in the CD player because moving parts are involved. These will produce friction and thus lose energy as heat.
e) Sustainable: A sustainable process is one that will not compromise the survival of future generations.
Disposal of used batteries from CD players is causing a pollution problem. Batteries must be developed that can easily be recharged and used for the life of the technology.
83. D 84. D 85. D 86. D 87. C 88. B 89. D 90. C 91. D 92. A 93. A 94. B 95. A 96. D 97. C 98. D 99. C 100. D 101. C
102. B 103. D
104. B 105. C 106. D 107. B
108. a) Low power field diameter = 4500 µm
high-power field diameter low-power magnification low-power field diameter high-power magnification
(4 )(4500 m) high power field diameter =
40
= 450m
b) length of onion cell = 450 µm
1 width of onion cell = 450 m
3
= 150 µm
109. Cell A: surface area = 6 s2
= 600 volume = s3
= 1000 surface to volume ratio = 0.6
Cell B: surface area = 2 lh + 2 lw + 2 wh
= 12 800 + 400 + 100 = 13 300
volume = l × w × h
= 8 000 surface to volume ratio = 1.66
Cell B has a greater surface to volume ratio, therefore it will have a faster rate of diffusion. 110. Cube: surface to volume ratio = A/v = 6s2 /s3 = 6/s = 6/5 = 1.2
111. 3, 1, 4, 2, 6, 5
112. Leaf A is probably Elodea, because it grows under water and would not need stomata for carbon dioxide entry. Carbon dioxide will diffuse into the leaf from the water. Thin leaves allow for a large surface to volume ratio for diffusion of carbon dioxide. It also would not need air spaces for carbon dioxide gas and to stay submersed.
Leaf B is probably water lily, which will receive sunlight on the upper surface. Chloroplasts here will capture sunlight. Stomata on the upper surface will allow carbon dioxide gas to enter. Air spaces will help it float. A thick cuticle will protect the surface and help keep it flat.
Leaf C is probably cattail. The leaf is in the air and stomata allow carbon dioxide entry at both surfaces. The cuticle reduces dehydration from both surfaces.
113. a) The stem will bend away from the auxin site because auxin causes stems to elongate.
b) Student answers will vary but should identify the variables to be controlled such as keeping the amount and direction of light the same for all plants. The amount of auxin mixture applied to each stem should be the same. Time between application of auxin and measuring should be constant for all plants. There should be at least two plants used for each concentration (two trials) for greater accuracy. Plants should be kept in the same area so that temperature, humidity, water supplied and light conditions are the same. Control plants should have the same amount of petroleum jelly applied with no auxin added. The method for measuring the degree of bending measurement should be included, and could involve using a protractor to measure the angle from the vertical.
114. Answers will include a description of the phospholipid bilayer as the matrix that holds the proteins. Channel proteins create pores to allow small water-soluble particles to cross. Carrier proteins attach to large molecules, change shape, and move the molecule across into the cell. Recognition proteins are embedded at the surface and allow cells to recognize each other and foreign substances. Receptor proteins at the surface may bind to molecules to carry them in by endocytosis or bind and trigger some action within the cell.
115. Spallanzani boiled broth, drew off the air and sealed the flask. This left the possibility of arguing that air was needed for spontaneous generation. Pasteur, however, boiled broth in flasks, which were open to the air, the only difference being in the shape of the neck. No organisms grew in the flask with the bent S-shaped neck. The only explanation was that organisms on dust particles settled out in the neck before reaching the broth. Therefore, organisms must come from other organisms. 116. a) Water moves by osmosis into the root hairs because minerals have been actively transported into the cells. Root pressure
builds up. As transpiration draws water from the leaf, water molecules move up the xylem ducts because they are attracted to each other (cohesion). Adhesion also helps water molecules climb up the xylem to the leaf. Water moves into the ground tissue for photosynthesis.
b) Sugar is produced in the ground tissue cells of the leaf. Companion cells of the phloem take in sugar by active
transport. Water follows by osmosis and then water and sugar move into the sieve cells. The result is increased pressure in the phloem. At the sink, sugar is moved into cells by active transport. These cells may be using the sugar for growth, respiration or storage. Water follows the sugar. This decreased pressure at the sink and the increased pressure at the source results in the movement of sugar from source to sink.
117. Students may choose to describe one of the following: liposomes used to deliver medications in HIV and cancer therapies, or to deliver DNA into tumor cells; peritoneal dialysis in which toxic substances diffuse into a dialysate in the abdominal cavity; hemodialysis in which blood passes by a dialysate and toxins diffuse across a membrane; or desalination of sea water by reverse osmosis.
