Semester Final--December 2018

Transcription

1 Semester Final--December 2018

2 1. The term biosphere refers to the parts of Earth that contain a. freshwater environments. b. living things. c. land masses. d. greater biodiversity. 2. Which phrase best describes Earth's biodiversity? a. greater in consistently warm areas b. greater toward Earth's poles c. greater according to energy needs d. greater where temperatures are most variable 3. An individual living thing is called a(n) a. species. b. cell. c. atom. d. organism. 4. Which of these characteristics is shared by all living things? a. They are made up of one or more cells. b. They make their own chemical energy. c. They have similar responses to light. d. They reproduce when one cell divides into two. 5. The basic unit of life is a. the cell. b. an atom. c. DNA. d. a species 6. At all levels of life, when related parts interact to form a whole they form a a. biosphere. b. species. c. cell. d. system. 7. Which statement best explains why the shape of teeth differs according to the diet of a species? a. Individual parts must work together. b. Organisms interact with other organisms. c. Structure and function are related in biology. d. Organisms must maintain homeostasis. 8. The maintenance of constant internal conditions in an organism is known as a. homeostasis. b. negative feedback. c. structure specialization. d. adaptation. 9. Which aspects of life on Earth are accounted for by evolution? a. diversity and unity

3 b. interaction and conflict c. lack of genetic and physical change d. divergence of structure and function 10. A beneficial inherited trait that is passed on to future generations is a(n) a. stimulus. b. adaptation. c. system. d. homeostatic mechanism. 11. Which word best describes a scientific hypothesis? a. provable b. theoretical c. testable d. quantifiable 12. At which stage of scientific inquiry would scientists find out if their hypotheses were supported by their data? a. observing b. testing hypotheses c. analyzing data d. evaluating results 13. In an experiment, the condition that is manipulated by a scientist is the a. independent variable. b. dependent variable. c. constant. d. control condition. 14. Which of the following is an important characteristic of a scientific theory? a. proven by more than one scientist b. unchanged by new evidence c. accepted by the public d. supported by much evidence 15. One way in which experimental research differs from observational research is that only experimental research can a. test a hypothesis. b. produce scientific results. c. support a theory. d. show cause and effect. 16. An electron microscope would be the best choice for viewing a. live bacteria. b. human ligaments. c. details of cell structure. d. a person's brain activity. 17. An injury that affects a ligament rather than a bone is likely to be examined using a. magnetic resonance imaging. b. x-rays.

4 c. computer modeling. d. transmission electron microscopy. 18. Complex studies, such as those that investigate disease transmission in humans, often use which of the following methods? a. multiple lab experiments b. computer modeling c. magnetic resonance imaging d. human testing 19. Which phrase best defines a gene? a. basic unit of life b. segment of DNA c. slice of a specimen d. inherited trait 20. Data mining contributes to the field of genomics by finding a. specimens on which to experiment. b. images of organisms. c. models of complex systems. d. patterns within data. 21. Knowledge of biology can promote advances by helping all people make a. strong opinions. b. informed decisions. c. profitable products. d. individual values. 22. The use and application of living things and biological processes is known as a. medical research. b. human biology. c. epidemiology. d. biotechnology. 23. Which of the following is an example of transgenic organisms? a. bacteria that produce human insulin b. microorganisms that produce cheese c. yeast used to produce bread d. algae that produce hydrogen gas 24. Biotechnology raises ethical questions, primarily concerning the a. safety of eating transgenic plants. b. wisdom of continuing to use technology. c. ways in which knowledge should be used. d. best use of funds for biological research. 25. Which is a true statement about biology's unanswered questions? a. unlikely to change anything b. many remain unasked c. few existed in the past

5 d. rarely depend on technology 26. Which phrase best describes atoms? a. single-celled organism b. smallest basic units of matter c. parts of a nucleus d. positively charged particles 27. Which of the following cannot be broken down by ordinary chemical means? a. element b. compound c. molecule d. bond 28. What is a compound? a. two atoms of a single element bonded together b. atoms of different elements bonded together in certain ratios c. separate atoms of multiple elements in varying ratios d. a molecule of two oxygen atoms 29. An ion is formed when an atom gains or loses a. protons. b. neutrons. c. bonds. d. electrons. 30. Atoms connected by covalent bonds share a. pairs of electrons. b. ionic compounds. c. carbon and oxygen. d. hydrogen ions. 31. Hydrogen bonds can form between regions of polar molecules that are a. nonpolar. b. negatively charged. c. oppositely charged. d. uncharged (neutral). 32. The attraction among molecules of different substances is called a. cohesion. b. adhesion. c. specific heat. d. surface tension. 33. Why is water necessary to your body? a. It prevents large changes in blood ph. b. It dissolves and transports substances. c. It dissolves nonpolar fats and oils.

6 d. It forms the solutes in blood plasma. 34. Which of the following phrases best describes a solvent? a. has a high concentration of solutes b. can be dissolved by the solute c. present in a greater concentration than solutes d. usually a sugar or a protein 35. A solution with a high concentration of H ions a. shows a ph of 7. b. kills all organisms. c. has a high ph. d. is very acidic. 36. Carbon is unique due to the carbon atom's a. bonding properties. b. six outer unpaired electrons. c. ionic compounds. d. hydrogen bonding strength. 37. Which category of carbon-based molecules includes sugars and starches? a. unsaturated fatty acids b. phospholipids c. proteins d. carbohydrates 38. Fats, oils, and cholesterol are all types of a. cell membranes. b. hormones. c. lipids. d. fatty acids. 39. Proteins are composed of which molecules? a. amino acids b. fatty acids c. monosaccharides d. nucleic acids 40. DNA and RNA are two types of a. proteins. b. nucleic acids. c. lipids. d. carbohydrates. 41. Chemical reactions change substances into different substances by a. conserving matter between the substances. b. breaking and forming chemical bonds. c. strengthening electrical charges of substances. d. changing a solvent into a solute.

7 42. Identify the reactants in the following chemical reaction: 6HO + 6CO a. 6 and 6 b. 6 and c. 6,, and 6 d. C6H12 and 6 CHO + 6O 43. The double arrows tell you that the following reaction a. takes place very rapidly. b. is very unstable. c. occurs in both directions. d. has high bond energies. 44. What is the term for the amount of energy that needs to be added for a chemical reaction to start? a. chemical energy b. activation energy c. bond energy d. reactant energy 45. Which phrase best describes an exothermic chemical reaction? a. does not absorb any energy b. forms products with higher bond energy than reactants c. is in a state of equilibrium d. releases more energy than it absorbs 46. Which phrase best describes the effect of a catalyst on a chemical reaction? a. increases the temperature b. increases the volume of reactants c. decreases the reaction rate d. decreases the activation energy 47. Which statement best describes the graph shown? a. More energy is released by the original reaction. b. Less energy is needed to start reaction B. c. The original reaction is catalyzed. d. Reaction B occurs at a slower rate. 48. Enzymes affect chemical reactions in living organisms by a. changing the direction of a reaction.

8 b. breaking down molecules into starch. c. increasing the temperature range. d. weakening bonds in reactants. 49. The specific reactants that an enzyme acts on are called a. catalysts b. proteins. c. substrates. d. amino acids. 50. Changes in temperature and ph can decrease an enzyme's activity by breaking a. hydrogen bonds b. peptide bonds c. amino acids d. sulfur-sulfur bonds 51. Which invention played the biggest role in the discovery of cells by early scientists? a. magnifying glass b. lens c. eyeglasses d. compound microscope 52. The cell theory states that all organisms are made of cells; cells are the most basic unit of life; and a. all existing cells form by free-cell formation. b. all cells are eukaryotic. c. all existing cells are produced by other living cells. d. all cells have a nucleus. 53. What is the term for the jellylike substance that is contained inside the cell membrane? a. cytoplasm b. DNA c. organelle d. nucleus 54. Unlike a eukaryotic cell, a prokaryotic cell does not have a. DNA. b. a cell membrane. c. cytoplasm. d. a nucleus. 55. Specialized structures that work together inside a cell are called a. organelles. b. prokaryotes. c. eukaryotes. d. nuclei. 56. Which of the following is a network of proteins that supports and gives shape to a cell? a. vesicles b. vacuole

9 c. cytoskeleton d. cytoplasm 57. What is the main function of the Golgi apparatus? a. communicate with other cells b. convert solar energy to chemical energy c. process and deliver proteins d. copy genetic material 58. Which of the following organelles can be found in the cytoplasm and on the surface of the endoplasmic reticulum? a. mitochondria b. centrosomes c. ribosomes d. centrioles 59. Which organelle contains enzymes that break down damaged cell parts? a. centriole b. lysosomes c. vacuole d. mitochondria 60. What are the main differences between plant and animal cells? a. Animal cells are eukaryotes and plant cells are not. b. Plant cells are eukaryotes and animal cells are not. c. Animal cells have cell walls and chloroplasts; plant cells do not. d. Plant cells have cell walls and chloroplasts; animal cells do not. 61. Which model did scientists develop to describe the cell membrane? a. phospholipid model b. dynamic model c. fluid mosaic model d. transport model 62. Which word best describes the structure of the cell membrane? a. layered b. rigid c. impermeable d. nonpolar 63. What is a phospholipid composed of? a. a polar head and a nonpolar tail b. a nonpolar head and a polar tail c. a polar head and tail d. a nonpolar head and tail

10 64. Which phrase best describes the property of selective permeability? a. some molecules pass b. all ions pass c. large molecules pass d. all molecules pass 65. A ligand produces a response in a cell if it finds the right kind of a. carbohydrate. b. hormone. c. membrane. d. receptor. 66. Which phrase best describes passive transport? a. requires transport proteins b. requires no energy from the cell c. requires an isotonic solution d. requires facilitation by enzymes 67. Water moves into a cell when the solution surrounding the cell is a. hypertonic. b. hypotonic. c. isotonic. d. concentrated. 68. What is the term for the diffusion of water across a semipermeable membrane? a. osmosis b. equilibrium c. transport d. isotonic 69. The movement of molecules down a concentration gradient through transport proteins in the cell membrane is a type of a. selective transport. b. osmosis. c. energy expenditure. d. facilitated diffusion. 70. The difference in the concentration of dissolved particles from one location to another is called a a. concentration gradient. b. concentrated solution. c. saline solution. d. dynamic gradient. 71. Unlike passive transport, active transport requires a. concentration gradients. b. diffusion. c. energy from the cell. d. vesicles. 72. Which process uses proteins to move molecules against a concentration gradient?

11 a. active transport b. passive transport c. endocytosis d. phagocytosis 73. Cells use active transport proteins to a. obtain molecules they need. b. break down molecules. c. engulf large particles. d. detect the charge of molecules. 74. A membrane-bound sac used to transport substances into and out of cells is a a. pump. b. macrophage. c. lysosome. d. vesicle. 75. Which process is used to release insulin from pancreatic cells into the bloodstream? a. exocytosis b. endocytosis c. active transport d. passive transport 76. Which of the following statements is true for all cells? a. They use solar energy. b. They use photosynthesis. c. They use chemical energy. d. They use chemosynthesis. 77. Which phrase best describes the function of the ATP molecule? a. stores energy b. carries energy c. absorbs energy d. converts energy 78. Where does the chemical energy to produce ATP come from? a. the conversion of ATP to ADP b. the use of chemicals from the environment to build sugars c. the addition of a phosphate group to ATP d. the breakdown of carbon-based molecules into smaller molecules 79. Energy is released from an ATP molecule for cellular processes when it a. has a phosphate group removed. b. stores an extra phosphate group. c. converts a phosphate group to ADP. d. produces a sugar molecule. 80. Which of the following is the source of energy used in chemosynthesis?

12 a. sunlight b. heat from hydrothermal vents c. chemical compounds d. amino acids 81. Which of the following statements best describes the process of photosynthesis? a. Plants use oxygen to make simple sugars. b. Chlorophyll builds sugars in the thylakoid membrane. c. Light breaks down water molecules and releases carbon dioxide. d. Chloroplasts absorb sunlight and store chemical energy. 82. What is the term for an organism that makes its own source of chemical energy? a. decomposer b. producer c. chloroplast d. protist 83. The main light-absorbing molecules found in plant leaves are called a. chloroplasts. b. thylakoids c. chlorophyll. d. grana. 84. The function of the light-dependent reactions is to a. build sugars. b. capture and transfer energy. c. release carbon dioxide. d. form water molecules. 85. The light-independent reactions of photosynthesis need a. carbon dioxide. b. oxygen. c. water. d. cellulose. 86. Which of the following types of organisms uses cellular respiration for their cellular energy needs? a. eukaryotes b. plants only c. animals only d. prokaryotes 87. Which process breaks down sugars to make ATP when oxygen is present? a. anaerobic respiration b. cellular respiration c. glycolysis d. photosynthesis

13 88. The part of cellular respiration in which glucose is broken down is called a. photosynthesis. b. aerobic respiration. c. electron transport. d. glycolysis. 89. Two products of the Krebs cycle are a. and. b. ATP and. c. ATP and. d. ADP and. 90. What provides the electron transport chain in cellular respiration with the energy it needs to function? a. ATP synthase b. glycolysis c. chlorophyll d. Krebs cycle 91. Which phrase best describes the main role of fermentation? a. converts glucose into pyruvate and NADH b. produces lactic acid to counteract an oxygen deficit c. allows glycolysis to continue making a small amount of ATP d. allowing anaerobic production of ADP 92. Which phrase about fermentation is correct? a. takes place without oxygen b. uses electron transport chain c. only occurs in bacteria d. is an aerobic process 93. Which end product of fermentation causes the burning feeling in muscles that are working hard? a. carbon dioxide b. pyruvate c. alcohol d. lactic acid 94. Why does a runner breathe hard for a few minutes after finishing a race? a. The runner's cells need oxygen to make lactic acid. b. The runner's cells continue the fermentation process. c. The runner's cells are making up for an oxygen deficit d. The runner's cells cannot perform glycolysis. 95. Which end product of alcoholic fermentation is important in the baking industry? a. lactic acid

14 b. carbon dioxide c. ATP molecules d. alcohol 96. In which stage of the cell cycle do the nucleus and its contents divide? a. synthesis b. gap 1 c. mitosis d. gap During the gap 1 stage of the cell cycle, a cell a. splits into two new cells. b. carries out its normal functions. c. duplicates its DNA. d. divides its cytoplasm. 98. Which of the following phrases best describes cytokinesis? a. division of the cytoplasm b. division of the nucleus c. division of DNA d. division of surface area 99. Which statement is true about the rates of cell division in eukaryotes? a. They remain the same for the life of the organism. b. They are faster than that of prokaryotes. c. They increase with the age of the organism. d. They vary greatly within an organism Which of the following limits the maximum size of a cell? a. the stage of the cell cycle b. the ratio of cell surface area to volume c. the number of mitochondria in the cell d. the size of the organism 101. The processes of mitosis and cytokinesis produce two identical a. daughter cells. b. strands c. chromosomes. d. chromatids The process of organizing and condensing DNA into its compact form takes place at the start of a. interphase. b. metaphase. c. mitosis. d. cytokinesis 103. Which is the term for the group of proteins that organizes and condenses long strands of DNA into tight coils? a. telomeres b. centromeres

15 c. chromatids d. histones 104. During which phase of mitosis do sister chromatids separate from each other? a. prophase b. metaphase c. anaphase d. telophase 105. Which of the following statements is true of cytokinesis? a. takes place in plant cells only b. completes the cell cycle c. organizes DNA d. occurs during prophase 106. Proteins that bind to cells and stimulate cell division are called a. enzymes. b. kinases. c. growth factors. d. carcinogens What is the term for the programmed death of cells? a. kinase b. cyclin c. carcinogen d. apoptosis 108. Two internal factors that are important in advancing the cell cycle are a. kinases and cyclins. b. hormones and enzymes. c. phosphates and enzymes. d. proteins and platelets Which phrase best describes cancer? a. absence of cyclins b. multiple gene mutations c. uncontrolled cell growth d. presence of genetic defects 110. Substances known to produce or promote cancer are called a. carcinogens. b. kinases. c. cyclins. d. malignancies The most common form of reproduction among prokaryotes is a. sexual reproduction. b. binary fission. c. budding. d. fragmentation.

16 112. What is the main difference between binary fission and mitosis? a. There is no DNA replication in binary fission. b. Two parents are required for mitotic reproduction. c. Binary fission occurs in single-celled organisms only. d. Mitosis takes place only in sexual reproduction Which of the following statements is true of asexual reproduction? a. It produces few offspring. b. It produces genetically identical offspring. c. It produces genetic diversity. d. It produces offspring that are resistant to antibiotics Starfish that reproduce by splitting into pieces are reproducing by a. binary fission. b. vegetative reproduction. c. budding. d. fragmentation Vegetative reproduction, budding, and fragmentation are examples of a. asexual mitotic reproduction. b. reproduction through binary fission. c. prokaryotic colony formation. d. increased genetic variation Which sequence shows the progression from least complex structure to most complex structure? a. cell organ tissue organ system b. cell tissue organ organ system c. organ system tissue organ cell d. organ system organ tissue cell 117. Which phrase best describes an organ system? a. group of specialized cells that forms organs b. group of cells that differentiates at the same rate c. group of tissues that performs a function d. group of organs that work together 118. Which of the following is a direct result of a normal cell's ability to express only certain genes? a. Cells can become totipotent. b. Cells can grow and reproduce. c. Cells can mutate and adapt. d. Cells can differentiate and specialize Stem cells are important to multicellular organisms because of their a. capacity to differentiate. b. tendency to maintain homeostasis.

17 c. potential to become totipotent. d. ability to relocate Which type of stem cell can grow into any other cell type? a. somatic b. multipotent c. totipotent d. pluripotent 121. Which result of Frederick Griffith's experiments led him to believe in a "transforming principle"? a. Mice injected with live S bacteria died. b. Mice injected with live R bacteria lived. c. Mice injected with dead S bacteria lived. d. Mice injected with dead S and live R bacteria died An important factor in Oswald Avery's ability to identify the "transforming principle" as DNA was the fact that proteins a. contain very little phosphorus. b. were present in the extract made from S bacteria. c. do not react with enzymes. d. could be observed in the extract made from R bacteria Chemical analysis of Avery's extracts showed that the ratio of nitrogen to phosphorus was consistent with that of a. enzymes. b. DNA. c. protein. d. bacteria Hershey and Chase chose to use bacteriophages in their experiments because these viruses a. contain little more than DNA and protein. b. can be seen with a light microscope. c. can infect only bacteria, not humans. d. will not grow in radioactive culture As a result of the Hershey and Chase experiments, scientists believe that a. radioactive isotopes can be used safely. b. viruses use bacterial DNA to reproduce. c. the "transforming principle" is DNA. d. bacteriophages can be grown in culture medium The four types of nucleotides that make up DNA are named for their a. hydrogen bonds. b. nitrogen-containing bases. c. phosphate groups. d. ring-shaped sugars.

18 127. After examining the DNA of different organisms, which of the following did Erwin Chargaff conclude about the four bases? a. A = T and C = G b. A = C = G = T c. A = C and G = T d. A + T = C + G 128. Which of the following DNA sequences is complementary to the base sequence ACCGTAT? a. GTTACGC b. UCCGTAT c. TGGCATA d. CAATGCG 129. Combining the work of other scientists with their own research, Watson and Crick discovered that two strands of DNA join together to form a(n) a. nucleotide. b. X in a circle. c. double helix. d. covalent bond What holds base pairs together? a. hydrogen bonds b. sugar-phosphate backbones c. pairs of double-ringed nucleotides d. nitrogen-carbon bonds 131. The process that makes an exact copy of a cell's DNA is called a. conservation. b. preservation. c. replication. d. synthesis What are the main functions of DNA polymerase? a. breaks hydrogen bonds and exposes bases b. holds DNA strands apart and attracts bases c. zips and unzips the double-stranded DNA d. binds nucleotides and corrects base pair errors 133. Which of the following events occurs directly after a DNA molecule is unzipped? a. Mismatched nucleotide bases are identified and replaced. b. Free-floating nucleotides pair up with exposed bases. c. Identical double-stranded DNA molecules are formed. d. Enzymes break hydrogen bonds between base pairs The process of making new DNA molecules is semiconservative. This means that every new DNA molecule is composed of

19 a. two completely identical strands of DNA. b. one original and one new strand of DNA. c. one strand of DNA and one strand of RNA. d. two strands that mix original and new DNA When new DNA molecules are formed, almost all errors are detected and fixed by a. the correct nucleotide. b. the sugar-phosphate backbone. c. DNA polymerase. d. one DNA strand Scientists use observations and data to form and test a. constants. b. hypotheses. c. theories. d. conclusions During an experiment, which factors are observed and measured? a. dependent variables b. independent variables c. constants d. hypotheses 138. At which stage of scientific thinking are scientists most likely to consider the data and conclusions of other scientists to propose new experiments? a. observing b. testing hypotheses c. analyzing data d. forming hypotheses 139. Which phrase best describes scientific theories? a. explain few observations b. serve as speculations c. are never proven d. cannot be replaced 140. The various parts of Earth's biosphere are connected and a. similar. b. nonliving. c. diverse. d. aquatic The variety of life across the biosphere is called

20 a. biodiversity. b. genomics. c. homeostasis. d. ecology Similar organisms that can reproduce by interbreeding belong to the same a. ecosystem. b. environment. c. habitat. d. species All the chemical processes used to build up or break down materials are called an organism's a. metabolism. b. homeostasis. c. adaptations. d. stimuli What is the name given for genetic changes in living things over time? a. adaptation b. homeostasis c. evolution d. negative feedback 145. A physical environment with different species that interact with one another and with nonliving things is called a(n) a. biosphere. b. ecosystem. c. habitat. d. adaptation Organisms rely on both negative feedback processes and behavior to maintain a. homeostasis. b. adaptations. c. ecosystems. d. evolution How have computer models expanded biological research? a. They help scientists design better experiments. b. They simulate complex biological systems that cannot be studied directly. c. They give scientists the ability to observe molecules directly. d. They allow the use of human experimental subjects The study and manipulation of DNA on a molecular level is known as a. biochemistry. b. genomes. c. molecular genetics. d. evolution.

21 149. Both of the processes shown in Figure 1.2 use and apply biological processes. Both processes are examples of a. biotechnology. b. genomics. c. imaging technology. d. transgenic organisms Exploring how indoor air pollutants lead to respiratory problems is an example of using biology to a. develop biotechnology. b. monitor global change. c. improve human health. d. make ethical decisions Which of the following is a major principle upon which cell theory is based? a. All cells form by free-cell formation. b. All cells have DNA. c. All organisms are made of cells. d. All cells are eukaryotic Identify the type of cell shown in Figure 3.1. a. prokaryotic b. eukaryotic c. bacterial d. animal 153. Which organelle is the storehouse for most of a cell's genetic information? a. mitochondrion b. chloroplast c. centriole d. nucleus

22 154. Which phrase best describes rough ER? a. studded with ribosomes b. protected by vesicles c. connected to the Golgi apparatus d. stored in the central vacuole 155. Which organelles supply energy to the cell? a. ribosomes b. centrosomes c. mitochondria d. vacuoles 156. Which organelles contain enzymes that break down old cell parts? a. centrosomes b. lysosomes c. vacuoles d. chloroplasts 157. Which organelles are unique to plant cells? a. ribosomes b. vacuoles c. chloroplasts d. centrosomes 158. Which process occurs inside the chloroplasts? a. detoxification b. ribosome assembly c. photosynthesis d. protein synthesis 159. Which type of receptor is shown in the diagram in Figure 3.2? a. cytoplasmic b. membrane c. extracellular d. intracellular 160. A protein that detects a signal molecule and performs an action in response is called a a. receptor. b. ligand. c. vesicle.

23 d. proton A solution that is hypotonic to a cell has a. more solutes than the cell. b. fewer solutes than the cell. c. the same concentration of solutes as the cell. d. too many solutes Transport proteins play a role in both a. passive and active transport. b. exocytosis and endocytosis. c. diffusion and vesicle transport. d. phagocytosis and passive transport Which process requires no energy from the cell? a. exocytosis b. endocytosis c. active transport d. facilitated diffusion 164. Which organelles are involved in the process called endocytosis? a. ribosomes b. vesicles c. centrioles d. chloroplasts 165. Which process is occurring when a vesicle fuses with the cell membrane and releases its contents outside the cell? a. endocytosis b. phagocytosis c. exocytosis d. osmosis 166. If a cell cannot move enough material through its membrane to survive, then the ratio of its surface area to volume is a. too large. b. just the right size. c. too small. d. growing too quickly Before a cell can proceed to mitosis from the gap 2 stage of the cell cycle, it must a. double in size. b. complete a full cell cycle. c. undergo cytokinesis. d. pass a critical checkpoint During interphase a cell grows, duplicates organelles, and a. copies DNA. b. divides the nucleus. c. divides the cytoplasm.

24 d. produces a new cell Why do the cells lining the stomach divide more quickly than those in the liver? a. They are much smaller cells. b. They have fewer chromosomes. c. They need much more surface area. d. They undergo more wear and tear During which of the following stages shown in Figure 5.1 does the cytoplasm of a cell divide? a. gap 1 b. synthesis c. gap 2 d. mitosis 171. Kinases and cyclins are internal factors that a. cause apoptosis. b. control the cell cycle. c. cause cancer cells to break away. d. prevent mitosis Proteins from outside a cell that stimulate it to divide are called a. oncogenes. b. stem cells. c. cyclins. d. growth factors Which statement describes the chromosome shown in Figure 5.2? a. It is made up of two histones. b. It is made up of two chromatids.

25 c. It is made up of two centromeres. d. It is made up of two telomeres In a single-celled organism, mitosis is used for a. development. b. reproduction. c. growth. d. epair Which of the following is true of malignant tumors? a. They do not require treatment. b. They are easily removed through surgery. c. They can cause tumors in other parts of the body. d. They contain cells that stay clustered together One difference between a cancer cell and a normal cell is that a. cancer cells divide uncontrollably. b. normal cells divide uncontrollably. c. cancer cells cannot make copies of DNA. d. normal cells cannot make copies of DNA Which statement about the process of binary fission is true? a. It does not involve the division of cytoplasm. b. It does not require any duplication of DNA. c. It does not take place in multicellular organisms. d. It does not produce genetically identical offspring A plant's leaf consists of a. a group of organs. b. various types of tissue. c. organs that form a system. d. many identical cells Cells in a developing embryo differentiate based on a. their location in the embryo. b. symmetry in the first division. c. their particular DNA. d. secretions from the embryo Which organism is capable of reproduction through asexual mitosis? a. horse b. oak tree c. bacterium d. starfish 181. The smallest basic unit of matter is the a. molecule.

26 b. atom. c. compound. d. cell Which of the following is formed when an atom gains or loses electrons? a. element b. compound c. molecule d. ion 183. Atoms in molecules share pairs of electrons when they make a. covalent bonds. b. ionic bonds. c. hydrogen bonds. d. polymers What gives water many properties that are important to living things? a. temperature b. hydrogen bonds c. density d. specific heat 185. Which of the following solutions has the highest H ion concentration? a. a solution with a ph of 1 b. a solution with a ph of 4 c. a solution with a ph of 7 d. a solution with a ph of What is unique about carbon? a. bonding properties b. ability to bond with oxygen c. properties as a reactant d. properties as an enzyme 187. Which substance represented in Figure 2.1 (A or B) is the solvent? a. both A and B b. substance A c. substance B d. neither A nor B

27 188. The four main types of carbon-based molecules in organisms are carbohydrates, lipids, nucleic acids, and a. starches. b. fatty acids. c. monosaccharides. d. proteins Both animal fats and plant oils are made up of glycerol and a. phospholipids. b. fatty acids. c. polar molecules. d. saturated fats Substances are changed into different substances when bonds break and form during a. chemical equilibrium. b. chemical reactions. c. ion formation. d. hydrogen bonding Identify the products in this reaction: 6HO + 6CO + CHO + 6O. a. 6 and 6 b. 6 and c. 6,, and 6 d. and Chemical reactions that absorb more energy than they release are called a. exothermic. b. catalyzed. c. endothermic. d. activated The activation energy needed for a chemical reaction is decreased by a a. catalyst. b. reactant. c. product. d. substrate In the lock-and-key model of enzyme function shown in Figure 2.2, what is happening in step 2? a. The catalyzed reaction is releasing a product. b. The active sites are restructuring the enzyme. c. The enzyme is causing new bonds to form between the substrates. d. The substrates are beginning to bind to the enzyme.

28 195. Which aspect of a chemical reaction is affected by enzymes? a. direction b. rate c. equilibrium d. ph 196. What did Hershey and Chase know about bacteriophages that led them to use these viruses in their DNA experiments? a. Bacteriophages are made up of a protein coat surrounding DNA. b. Sulfur in all bacteriophages is radioactive. c. Protein from bacteriophages enters bacteria. d. Bacteriophages have no DNA of their own Which scientist conducted tests on extracts made of bacteria to show that the genetic material in bacteria is DNA? a. Martha Chase b. Oswald Avery c. Frederick Griffith d. Alfred Hershey 198. Figure 8.1 shows a single strand of DNA. Choose the first three nucleotides of the other DNA strand. a. GGT b. CCT c. GGC d. TTA 199. The main difference between the four nucleotides that make up DNA is that they have different a. sugars. b. uracil. c. bonds. d. bases In humans, where does DNA replication take place? a. cytoplasm b. ribosome c. nucleus d. vacuole