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Biology for AP® Courses

Critical Thinking Questions

Biology for AP® CoursesCritical Thinking Questions
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  1. Preface
  2. Unit 1
    1. 1 The Study of Life
      1. Introduction
      2. 1.1 The Science of Biology
      3. 1.2 Themes and Concepts of Biology
      4. Key Terms
      5. Chapter Summary
      6. Review Questions
      7. Critical Thinking Questions
      8. Test Prep for AP® Courses
    2. 2 The Chemical Foundation of Life
      1. Introduction
      2. 2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks
      3. 2.2 Water
      4. 2.3 Carbon
      5. Key Terms
      6. Chapter Summary
      7. Review Questions
      8. Critical Thinking Questions
      9. Test Prep for AP® Courses
      10. Science Practice Challenge Questions
    3. 3 Biological Macromolecules
      1. Introduction
      2. 3.1 Synthesis of Biological Macromolecules
      3. 3.2 Carbohydrates
      4. 3.3 Lipids
      5. 3.4 Proteins
      6. 3.5 Nucleic Acids
      7. Key Terms
      8. Chapter Summary
      9. Review Questions
      10. Critical Thinking Questions
      11. Test Prep for AP® Courses
      12. Science Practice Challenge Questions
  3. Unit 2
    1. 4 Cell Structure
      1. Introduction
      2. 4.1 Studying Cells
      3. 4.2 Prokaryotic Cells
      4. 4.3 Eukaryotic Cells
      5. 4.4 The Endomembrane System and Proteins
      6. 4.5 Cytoskeleton
      7. 4.6 Connections between Cells and Cellular Activities
      8. Key Terms
      9. Chapter Summary
      10. Review Questions
      11. Critical Thinking Questions
      12. Test Prep for AP® Courses
      13. Science Practice Challenge Questions
    2. 5 Structure and Function of Plasma Membranes
      1. Introduction
      2. 5.1 Components and Structure
      3. 5.2 Passive Transport
      4. 5.3 Active Transport
      5. 5.4 Bulk Transport
      6. Key Terms
      7. Chapter Summary
      8. Review Questions
      9. Critical Thinking Questions
      10. Test Prep for AP® Courses
      11. Science Practice Challenge Questions
    3. 6 Metabolism
      1. Introduction
      2. 6.1 Energy and Metabolism
      3. 6.2 Potential, Kinetic, Free, and Activation Energy
      4. 6.3 The Laws of Thermodynamics
      5. 6.4 ATP: Adenosine Triphosphate
      6. 6.5 Enzymes
      7. Key Terms
      8. Chapter Summary
      9. Review Questions
      10. Critical Thinking Questions
      11. Test Prep for AP® Courses
      12. Science Practice Challenge Questions
    4. 7 Cellular Respiration
      1. Introduction
      2. 7.1 Energy in Living Systems
      3. 7.2 Glycolysis
      4. 7.3 Oxidation of Pyruvate and the Citric Acid Cycle
      5. 7.4 Oxidative Phosphorylation
      6. 7.5 Metabolism without Oxygen
      7. 7.6 Connections of Carbohydrate, Protein, and Lipid Metabolic Pathways
      8. 7.7 Regulation of Cellular Respiration
      9. Key Terms
      10. Chapter Summary
      11. Review Questions
      12. Critical Thinking Questions
      13. Test Prep for AP® Courses
      14. Science Practice Challenge Questions
    5. 8 Photosynthesis
      1. Introduction
      2. 8.1 Overview of Photosynthesis
      3. 8.2 The Light-Dependent Reaction of Photosynthesis
      4. 8.3 Using Light to Make Organic Molecules
      5. Key Terms
      6. Chapter Summary
      7. Review Questions
      8. Critical Thinking Questions
      9. Test Prep for AP® Courses
      10. Science Practice Challenge Questions
    6. 9 Cell Communication
      1. Introduction
      2. 9.1 Signaling Molecules and Cellular Receptors
      3. 9.2 Propagation of the Signal
      4. 9.3 Response to the Signal
      5. 9.4 Signaling in Single-Celled Organisms
      6. Key Terms
      7. Chapter Summary
      8. Review Questions
      9. Critical Thinking Questions
      10. Test Prep for AP® Courses
      11. Science Practice Challenge Questions
    7. 10 Cell Reproduction
      1. Introduction
      2. 10.1 Cell Division
      3. 10.2 The Cell Cycle
      4. 10.3 Control of the Cell Cycle
      5. 10.4 Cancer and the Cell Cycle
      6. 10.5 Prokaryotic Cell Division
      7. Key Terms
      8. Chapter Summary
      9. Review Questions
      10. Critical Thinking Questions
      11. Test Prep for AP® Courses
      12. Science Practice Challenge Questions
  4. Unit 3
    1. 11 Meiosis and Sexual Reproduction
      1. Introduction
      2. 11.1 The Process of Meiosis
      3. 11.2 Sexual Reproduction
      4. Key Terms
      5. Chapter Summary
      6. Review Questions
      7. Critical Thinking Questions
      8. Test Prep for AP® Courses
      9. Science Practice Challenge Questions
    2. 12 Mendel's Experiments and Heredity
      1. Introduction
      2. 12.1 Mendel’s Experiments and the Laws of Probability
      3. 12.2 Characteristics and Traits
      4. 12.3 Laws of Inheritance
      5. Key Terms
      6. Chapter Summary
      7. Review Questions
      8. Critical Thinking Questions
      9. Test Prep for AP® Courses
      10. Science Practice Challenge Questions
    3. 13 Modern Understandings of Inheritance
      1. Introduction
      2. 13.1 Chromosomal Theory and Genetic Linkages
      3. 13.2 Chromosomal Basis of Inherited Disorders
      4. Key Terms
      5. Chapter Summary
      6. Review Questions
      7. Critical Thinking Questions
      8. Test Prep for AP® Courses
      9. Science Practice Challenge Questions
    4. 14 DNA Structure and Function
      1. Introduction
      2. 14.1 Historical Basis of Modern Understanding
      3. 14.2 DNA Structure and Sequencing
      4. 14.3 Basics of DNA Replication
      5. 14.4 DNA Replication in Prokaryotes
      6. 14.5 DNA Replication in Eukaryotes
      7. 14.6 DNA Repair
      8. Key Terms
      9. Chapter Summary
      10. Review Questions
      11. Critical Thinking Questions
      12. Test Prep for AP® Courses
      13. Science Practice Challenge Questions
    5. 15 Genes and Proteins
      1. Introduction
      2. 15.1 The Genetic Code
      3. 15.2 Prokaryotic Transcription
      4. 15.3 Eukaryotic Transcription
      5. 15.4 RNA Processing in Eukaryotes
      6. 15.5 Ribosomes and Protein Synthesis
      7. Key Terms
      8. Chapter Summary
      9. Review Questions
      10. Critical Thinking Questions
      11. Test Prep for AP® Courses
      12. Science Practice Challenge Questions
    6. 16 Gene Regulation
      1. Introduction
      2. 16.1 Regulation of Gene Expression
      3. 16.2 Prokaryotic Gene Regulation
      4. 16.3 Eukaryotic Epigenetic Gene Regulation
      5. 16.4 Eukaryotic Transcriptional Gene Regulation
      6. 16.5 Eukaryotic Post-transcriptional Gene Regulation
      7. 16.6 Eukaryotic Translational and Post-translational Gene Regulation
      8. 16.7 Cancer and Gene Regulation
      9. Key Terms
      10. Chapter Summary
      11. Review Questions
      12. Critical Thinking Questions
      13. Test Prep for AP® Courses
      14. Science Practice Challenge Questions
    7. 17 Biotechnology and Genomics
      1. Introduction
      2. 17.1 Biotechnology
      3. 17.2 Mapping Genomes
      4. 17.3 Whole-Genome Sequencing
      5. 17.4 Applying Genomics
      6. 17.5 Genomics and Proteomics
      7. Key Terms
      8. Chapter Summary
      9. Review Questions
      10. Critical Thinking Questions
      11. Test Prep for AP® Courses
      12. Science Practice Challenge Questions
  5. Unit 4
    1. 18 Evolution and Origin of Species
      1. Introduction
      2. 18.1 Understanding Evolution
      3. 18.2 Formation of New Species
      4. 18.3 Reconnection and Rates of Speciation
      5. Key Terms
      6. Chapter Summary
      7. Review Questions
      8. Critical Thinking Questions
      9. Test Prep for AP® Courses
      10. Science Practice Challenge Questions
    2. 19 The Evolution of Populations
      1. Introduction
      2. 19.1 Population Evolution
      3. 19.2 Population Genetics
      4. 19.3 Adaptive Evolution
      5. Key Terms
      6. Chapter Summary
      7. Review Questions
      8. Critical Thinking Questions
      9. Test Prep for AP® Courses
      10. Science Practice Challenge Questions
    3. 20 Phylogenies and the History of Life
      1. Introduction
      2. 20.1 Organizing Life on Earth
      3. 20.2 Determining Evolutionary Relationships
      4. 20.3 Perspectives on the Phylogenetic Tree
      5. Key Terms
      6. Chapter Summary
      7. Review Questions
      8. Critical Thinking Questions
      9. Test Prep for AP® Courses
      10. Science Practice Challenge Questions
  6. Unit 5
    1. 21 Viruses
      1. Introduction
      2. 21.1 Viral Evolution, Morphology, and Classification
      3. 21.2 Virus Infection and Hosts
      4. 21.3 Prevention and Treatment of Viral Infections
      5. 21.4 Other Acellular Entities: Prions and Viroids
      6. Key Terms
      7. Chapter Summary
      8. Review Questions
      9. Critical Thinking Questions
      10. Test Prep for AP® Courses
      11. Science Practice Challenge Questions
    2. 22 Prokaryotes: Bacteria and Archaea
      1. Introduction
      2. 22.1 Prokaryotic Diversity
      3. 22.2 Structure of Prokaryotes
      4. 22.3 Prokaryotic Metabolism
      5. 22.4 Bacterial Diseases in Humans
      6. 22.5 Beneficial Prokaryotes
      7. Key Terms
      8. Chapter Summary
      9. Review Questions
      10. Critical Thinking Questions
      11. Test Prep for AP® Courses
      12. Science Practice Challenge Questions
  7. Unit 6
    1. 23 Plant Form and Physiology
      1. Introduction
      2. 23.1 The Plant Body
      3. 23.2 Stems
      4. 23.3 Roots
      5. 23.4 Leaves
      6. 23.5 Transport of Water and Solutes in Plants
      7. 23.6 Plant Sensory Systems and Responses
      8. Key Terms
      9. Chapter Summary
      10. Review Questions
      11. Critical Thinking Questions
      12. Test Prep for AP® Courses
      13. Science Practice Challenge Questions
  8. Unit 7
    1. 24 The Animal Body: Basic Form and Function
      1. Introduction
      2. 24.1 Animal Form and Function
      3. 24.2 Animal Primary Tissues
      4. 24.3 Homeostasis
      5. Key Terms
      6. Chapter Summary
      7. Review Questions
      8. Critical Thinking Questions
      9. Test Prep for AP® Courses
    2. 25 Animal Nutrition and the Digestive System
      1. Introduction
      2. 25.1 Digestive Systems
      3. 25.2 Nutrition and Energy Production
      4. 25.3 Digestive System Processes
      5. 25.4 Digestive System Regulation
      6. Key Terms
      7. Chapter Summary
      8. Review Questions
      9. Critical Thinking Questions
      10. Test Prep for AP® Courses
      11. Science Practice Challenge Questions
    3. 26 The Nervous System
      1. Introduction
      2. 26.1 Neurons and Glial Cells
      3. 26.2 How Neurons Communicate
      4. 26.3 The Central Nervous System
      5. 26.4 The Peripheral Nervous System
      6. 26.5 Nervous System Disorders
      7. Key Terms
      8. Chapter Summary
      9. Review Questions
      10. Critical Thinking Questions
      11. Test Prep for AP® Courses
      12. Science Practice Challenge Questions
    4. 27 Sensory Systems
      1. Introduction
      2. 27.1 Sensory Processes
      3. 27.2 Somatosensation
      4. 27.3 Taste and Smell
      5. 27.4 Hearing and Vestibular Sensation
      6. 27.5 Vision
      7. Key Terms
      8. Chapter Summary
      9. Review Questions
      10. Critical Thinking Questions
      11. Science Practice Challenge Questions
    5. 28 The Endocrine System
      1. Introduction
      2. 28.1 Types of Hormones
      3. 28.2 How Hormones Work
      4. 28.3 Regulation of Body Processes
      5. 28.4 Regulation of Hormone Production
      6. 28.5 Endocrine Glands
      7. Key Terms
      8. Chapter Summary
      9. Review Questions
      10. Critical Thinking Questions
      11. Test Prep for AP® Courses
      12. Science Practice Challenge Questions
    6. 29 The Musculoskeletal System
      1. Introduction
      2. 29.1 Types of Skeletal Systems
      3. 29.2 Bone
      4. 29.3 Joints and Skeletal Movement
      5. 29.4 Muscle Contraction and Locomotion
      6. Key Terms
      7. Chapter Summary
      8. Review Questions
      9. Critical Thinking Questions
      10. Science Practice Challenge Questions
    7. 30 The Respiratory System
      1. Introduction
      2. 30.1 Systems of Gas Exchange
      3. 30.2 Gas Exchange across Respiratory Surfaces
      4. 30.3 Breathing
      5. 30.4 Transport of Gases in Human Bodily Fluids
      6. Key Terms
      7. Chapter Summary
      8. Review Questions
      9. Critical Thinking Questions
      10. Test Prep for AP® Courses
      11. Science Practice Challenge Questions
    8. 31 The Circulatory System
      1. Introduction
      2. 31.1 Overview of the Circulatory System
      3. 31.2 Components of the Blood
      4. 31.3 Mammalian Heart and Blood Vessels
      5. 31.4 Blood Flow and Blood Pressure Regulation
      6. Key Terms
      7. Chapter Summary
      8. Review Questions
      9. Critical Thinking Questions
      10. Test Prep for AP® Courses
      11. Science Practice Challenge Questions
    9. 32 Osmotic Regulation and Excretion
      1. Introduction
      2. 32.1 Osmoregulation and Osmotic Balance
      3. 32.2 The Kidneys and Osmoregulatory Organs
      4. 32.3 Excretion Systems
      5. 32.4 Nitrogenous Wastes
      6. 32.5 Hormonal Control of Osmoregulatory Functions
      7. Key Terms
      8. Chapter Summary
      9. Review Questions
      10. Critical Thinking Questions
      11. Test Prep for AP® Courses
    10. 33 The Immune System
      1. Introduction
      2. 33.1 Innate Immune Response
      3. 33.2 Adaptive Immune Response
      4. 33.3 Antibodies
      5. 33.4 Disruptions in the Immune System
      6. Key Terms
      7. Chapter Summary
      8. Review Questions
      9. Critical Thinking Questions
      10. Test Prep for AP® Courses
      11. Science Practice Challenge Questions
    11. 34 Animal Reproduction and Development
      1. Introduction
      2. 34.1 Reproduction Methods
      3. 34.2 Fertilization
      4. 34.3 Human Reproductive Anatomy and Gametogenesis
      5. 34.4 Hormonal Control of Human Reproduction
      6. 34.5 Fertilization and Early Embryonic Development
      7. 34.6 Organogenesis and Vertebrate Formation
      8. 34.7 Human Pregnancy and Birth
      9. Key Terms
      10. Chapter Summary
      11. Review Questions
      12. Critical Thinking Questions
      13. Test Prep for AP® Courses
      14. Science Practice Challenge Questions
  9. Unit 8
    1. 35 Ecology and the Biosphere
      1. Introduction
      2. 35.1 The Scope of Ecology
      3. 35.2 Biogeography
      4. 35.3 Terrestrial Biomes
      5. 35.4 Aquatic Biomes
      6. 35.5 Climate and the Effects of Global Climate Change
      7. Key Terms
      8. Chapter Summary
      9. Review Questions
      10. Critical Thinking Questions
      11. Test Prep for AP® Courses
      12. Science Practice Challenge Questions
    2. 36 Population and Community Ecology
      1. Introduction
      2. 36.1 Population Demography
      3. 36.2 Life Histories and Natural Selection
      4. 36.3 Environmental Limits to Population Growth
      5. 36.4 Population Dynamics and Regulation
      6. 36.5 Human Population Growth
      7. 36.6 Community Ecology
      8. 36.7 Behavioral Biology: Proximate and Ultimate Causes of Behavior
      9. Key Terms
      10. Chapter Summary
      11. Review Questions
      12. Critical Thinking Questions
      13. Test Prep for AP® Courses
      14. Science Practice Challenge Questions
    3. 37 Ecosystems
      1. Introduction
      2. 37.1 Ecology for Ecosystems
      3. 37.2 Energy Flow through Ecosystems
      4. 37.3 Biogeochemical Cycles
      5. Key Terms
      6. Chapter Summary
      7. Review Questions
      8. Critical Thinking Questions
      9. Test Prep for AP® Courses
      10. Science Practice Challenge Questions
    4. 38 Conservation Biology and Biodiversity
      1. Introduction
      2. 38.1 The Biodiversity Crisis
      3. 38.2 The Importance of Biodiversity to Human Life
      4. 38.3 Threats to Biodiversity
      5. 38.4 Preserving Biodiversity
      6. Key Terms
      7. Chapter Summary
      8. Review Questions
      9. Critical Thinking Questions
      10. Test Prep for AP® Courses
  10. A | The Periodic Table of Elements
  11. B | Geological Time
  12. C | Measurements and the Metric System
  13. Index
54.
Describe how a researcher could determine the population size and density of a bird population on one of the Hawaiian islands.
  1. Population size can be determined by life tables. The area of the island in square kilometers is divided by the population size to determine the density of the bird population.
  2. Population size can be determined by the mark and recapture method. The population size is divided by the area of the island in square kilometers to determine the density of the bird population.
  3. Population size can be determined by life tables. The population size is divided by the area of the island in square kilometers to determine the density of the bird population.
  4. Population size can be determined by the mark and recapture method. The area of the island in square kilometers is divided by the population size to determine the density of the bird population.
55.
Give examples of how two different populations of organisms might have the same population density, but different dispersal patterns.
  1. Two populations could occupy the same range with the same number of individuals, giving different dispersal patterns. However, both the populations may be dispersed randomly throughout the range, giving identical population densities.
  2. Two populations could occupy the different range with the different number of individuals, giving different dispersal patterns. However, both the populations may move over this range in a herd, giving identical population densities.
  3. Two populations could occupy the same range with the different number of individuals, giving identical population densities. However, one population may move over this range in a herd while the other population may be dispersed randomly throughout the range.
  4. Two populations could occupy the same range with the same number of individuals, giving identical population densities. However, one population may move over this range in a herd while the other population may be dispersed randomly throughout the range.
56.
A population is observed to have very large numbers of very young individuals, but very low numbers of sexually mature individuals. What hypothesis might a researcher propose about mortality patterns in this population and how would a researcher follow up to test their hypothesis?
  1. A researcher might propose the mortality rate of this species is very high during the developmental period after sexual maturity is reached. This hypothesis can be tested by constructing a life table and calculating mortality rates at different age intervals.
  2. A researcher might propose the mortality rate of this species is very high during the developmental period before sexual maturity is reached. This hypothesis can be tested by using the mark and recapture method and calculating population densities.
  3. A researcher might propose the mortality rate of this species is very high during the developmental period before sexual maturity is reached. This hypothesis can be tested by constructing a life table and calculating mortality rates at different age intervals.
  4. A researcher might propose the mortality rate of this species is very low during the developmental period before sexual maturity is reached. This hypothesis can be tested by constructing a quadrat and calculating mortality rates at different age intervals.
57.
An organism, such as an elephant, that invests in long-term care of its offspring faces risks to its survival as a result of this investment. Explain those risks.
  1. Organisms that invest in long-term parental care have many offspring. Having many offspring means there is greater risk of rapid increase in population.
  2. Organisms that invest in long-term parental care have few offspring. Having a limited number of offspring means there is greater risk to the survival of the species when a single offspring dies.
  3. Organisms that invest in long-term parental care have many offspring. Having many offspring means there is greater risk to the survival of the species when a single offspring dies.
  4. Organisms that invest in long-term parental care have few offspring. Having a limited number of offspring means there is greater risk of rapid increase in population.
58.
A honey bee colony contains one queen, hundreds of drones, and many thousands of worker bees. The queen produces eggs, the drones produce sperm, and the workers are sterile. Explain how the reproductive strategy of honey bees benefits the survival of the species. (credit: Food and Agriculture Organization of the United Nations)
  1. The fertile queen and drones produce many offspring while sterile worker bees do not benefit the survival of the species.
  2. Worker bees produce many offspring while the sterile queen and drones do not benefit the survival of the species.
  3. The sterile queen and drones use the energy taken in by them for their own growth, growth and maintenance of the hive, and protection and nurturing of offspring.
  4. Sterile worker bees use the energy taken in by them for their own growth, growth and maintenance of the hive, and protection and nurturing of offspring.
59.
Two different plant species expend approximately the same amount of energy on reproduction, yet one produces many seeds in a season and the other produces very few. Explain what is likely to be true of the seeds of these two species.
  1. In the plant species that produces many seeds, most of the energy is used to produce seeds, of which only a few will germinate and produce another plant. In the species that produces few seeds, most of the energy is used to increase the chances of seeds produced to germinate and grow into an adult plant.
  2. In a plant species that produces many seeds, most of the energy is used to produce seeds, most of which will germinate and produce another plant. In a species that produces few seeds, most of the energy is used to increase the chances of seeds produced to germinate and grow into an adult plant.
  3. In a plant species that produces many seeds, most of the energy is used to produce seeds, of which only a few will germinate and produce another plant. In a species that produces few seeds, most of the energy is used to reduce the chances of seeds produced to germinate and grow into an adult plant.
  4. In a plant species that produces many seeds, most of the energy is used to increase the chances of seeds produced to germinate and grow into an adult plant. In a species that produces few seeds, most of the energy is used to produce those seeds, which will germinate and produce another plant.
60.
Explain how rmax would be expected to differ for an elephant and a flea, and how that changes the time scale over which populations of these two animals would be studied.
  1. rmax would be greater for an elephant as elephant reproduces at a faster rate than flea. A shorter time scale would be used to study changes over several elephant generations.
  2. rmax would be greater for a flea as flea reproduces at a faster rate than elephant. A shorter time scale would be used to study changes over several flea generations than over several elephant generations.
  3. rmax would be greater for a flea as flea reproduces at a faster rate than elephant. A longer time scale would be used to study changes over several flea generations than over several elephant generations.
  4. rmax would be greater for an elephant as the elephants grow at an exponential rate so the population growth rate is greatly increased. A shorter time scale would be used to study changes over several elephant generations.
61.

The table has two columns, date and N. The date 5/1/12 corresponds with N 56, 6/1/12 with 98, 7/2/12 with 203, and 8/10/12 with 421.

These data were collected on a population of beetles in Florida. Based on the data, how would you describe population growth in this case and what do you predict about growth of this population in the future? Explain your reasoning.

  1. Population shows logistic growth, as number of individuals doubles every month and will likely continue to grow logistically until its resources become depleted. At that point, the population growth rate will slow down and level off to zero.
  2. The population shows exponential growth, as the number of individuals doubles every month and will likely grow logistically in the future when the resources become limited. At that point, the population growth rate will slow down and level off to zero.
  3. The population shows exponential growth, as number of individuals doubles every month and will likely continue to grow exponentially until its resources become limited. At that point, the growth will become logistic; the population growth rate will slow down and level off to zero.
  4. The population shows logistic growth and is likely to grow exponentially as the resources are probably increasing. The population growth rate will increase in the future as well.
62.
Explain how climate change might lead to a decrease in one population’s carrying capacity and an increase in the carrying capacity of a different population.
  1. Plant species that are drought-resistant would decline in warm temperatures whereas other species would thrive in number in such a climate.
  2. Plant species that are pest-resistant would thrive in warm temperatures whereas other species would decline in number in such a climate.
  3. Plant species that are drought-resistant would decline in cold temperatures whereas other species would thrive in number in such a climate.
  4. Plant species that are drought-resistant would thrive in warm temperatures whereas other species would decline in number in such a climate.
63.
Compare and contrast density-dependent growth regulation with density-independent growth regulation. Give an example of each as they might affect a caterpillar population.
  1. Both are environmental conditions that result in changes in population numbers. Density-independent factors have different effects on population densities whereas density-dependent factors have the same effect. An example of the former is a caterpillar population being kept low by a pesticide because it kills them regardless of their numbers. In the case of the latter, a large caterpillar population leads to a decrease in food availability, which will cause the caterpillar population to decline.
  2. Both are environmental conditions that result in changes in population numbers. Density-independent factors have the same effect at all population densities whereas density-dependent factors have different effects. An example of the former is of a caterpillar population being kept low by a pesticide because it kills them regardless of their numbers. In the case of the latter, a large caterpillar population leads to a decrease in food availability, which will cause the caterpillar population to decline.
  3. Both are environmental conditions that result in changes in population numbers. Density-independent factors have the same effect at all population densities whereas density-dependent factors have different effects. An example of the former is of a caterpillar population being kept low by a pesticide because it kills them when their numbers are low. In the case of the latter, a large caterpillar population leads to a decrease in food availability, which will cause the caterpillar population to decline.
  4. Both are environmental conditions that result in changes in population numbers. Density-independent factors have the same effect at all population densities whereas density-dependent factors have different effects. An example of the former is of a caterpillar population being kept low by a pesticide because it kills them regardless of their numbers. In the case of the latter, a large caterpillar population leads to a decrease in food availability, which will cause the caterpillar population to increase.
64.
Why doesn’t a frog, which is an r-selected species, care for its offspring in the way a wolf, which is a K-selected species, cares for its offspring?
  1. Frogs have been selected by stable, predictable environments, therefore they do not feel the need to care for their offspring like wolves.
  2. Frogs use very little energy to produce large numbers of offspring, therefore they do not have enough remaining to nurture them.
  3. Smaller animals like frogs do not care for their offspring as a lot of them are produced whereas larger animals like wolves only produce a few.
  4. Frogs expend a lot of energy to produce large numbers of offspring, therefore they do not have enough to nurture them.
65.
Explain which features of a logistic growth curve are the same for every population exhibiting logistic growth and which features might vary from one population to another.
  1. The overall S-shape would be the same for all populations. The actual x-y values on the graphs, population numbers corresponding to starting populations, and the ending carrying capacities could differ.
  2. The overall carrying capacities would be the same for all populations. The actual x-y values on the graph and population numbers corresponding to the starting populations could differ.
  3. The overall S-shape would be the same for all populations showing logistic growth. The only factor that could differ is the actual x-y values on the graphs indicating the time frames for the growth curves.
  4. The x-y values on the graphs indicating the time frames for the growth curves would be the same. Overall S shape and population numbers corresponding to the starting populations could differ.
66.
Explain why the concept of carrying capacity is important when discussing human population growth.
  1. Humans can decrease the carrying capacity of their environment by developing food production methods and engineering high quality shelters, which enables more people to live than would otherwise be possible.
  2. Humans have been able to change the carrying capacity of their environment, which enables more people survive. By decreasing their own carrying capacity, humans are responsible for their population boom.
  3. Humans have been able to change the carrying capacity of their environment, which enables more people to live. By increasing their own carrying capacity, humans are responsible for their population boom.
  4. Humans can increase the carrying capacity of their environment by developing food production methods and engineering high quality shelters, which enables fewer people to live than would otherwise be possible. This would result in population collapse.
67.
The Industrial Revolution began with the invention of the steam engine. At about the same time, human population began increasing exponentially. Explain how these two events are linked to the idea that humans are able to change the carrying capacity of their environment.
  1. The invention of the steam engine enabled people to use machines to carry out farming activities. The amount of available resources needed to sustain human life increased with the invention of machines. This increase in resources spurred exponential population growth.
  2. The invention of the steam engine enabled people to develop pest-resistant crop varieties. The amount of available resources needed to sustain human life increased with the invention of machines. This increase in resources spurred exponential population growth.
  3. The amount of available resources needed to sustain human life decreased with the invention of machines, but the carrying capacity increased. This increase in carrying capacity spurred exponential population growth.
  4. The invention of the steam engine enables the environment to be changed according to the needs of the people. This regulation of environmental conditions spurred exponential population growth.
68.

An age structure diagram is shown on a graph.  The x axis is labeled percent of population, the y axis is labeled in increments of 4, starting from 0–4 and ending at 80+, designating age groups of the population.  The left side is male and the right side is female.  The population starts at about 4% of males and females age 0–4, tapers in slightly and budges out for ages 30–34 and 34–39, going beyond 4%.  Then, the percentages taper down until 80+, where the male is about 1% and the females remain at 2%, which is a slightly higher number than their population at 75–79.  The Female population after about 40–44 is stays at a slightly higher population percentage than the males.

(credit: Quia) This diagram shows the age structure for a country. Analyze the age structure and use it to predict the economic status of this country. Explain your reasoning.

  1. This country is likely to be an economically developing country because it has a fairly even distribution of individuals in all age groups.
  2. This country is likely to be an economically developed country because it has many more very young people and very few old people.
  3. This country is likely to be an economically developed country because it has a fairly even distribution of individuals in all age groups.
  4. This country is likely to be an economically undeveloped country because it has many more very young people and very few old people.
69.

Graph shown with title “Humanity’s Ecological Footprint, 1961–2003.” The x axis in years, ranging from 1961 to 2003.  The y axis is labeled, “Number of planet Earths,” ranging from 0 to 1.8.  A fairly straight line ranges from (1961, 0.45) to (2003, 1.2).

(credit: EPA Victoria) The global ecological footprint is defined as the total land area needed to supply all of the resources consumed by all humans. This graph shows the relationship between time and the global human footprint measured in number of planet Earths. Analyze the graph, and use it to explain what has been the consequence of human population change so far. Then, predict the consequences of continued population change in the future.

  1. The water resources present on Earth has been exceeded by the human population. If the human population keeps increasing, the ecological footprint of humans will increase far beyond the ability of Earth to support human population and our population could crash.
  2. The land area present on Earth to supply our resources has been exceeded by the human population. If the human population keeps increasing, the ecological footprint of humans will increase far beyond the ability of Earth to support human population and our population could crash.
  3. The land area present on Earth to supply our resources has been exceeded by the human population. If the human population keeps increasing, the birth and death rates will decrease and our population could crash.
  4. The water resources present on Earth has been exceeded by the human population. If the human population keeps increasing, the birth and death rates will decrease and our population could crash.
70.

A graph with the x-axis labeled “Year” ranging from 1955 to 1995 in increments of 5. The left y-axis is labeled “Number of wolves” and ranges from 0 to 60.  The right y-axis is labeled “Number of moose” and is labeled from 0 to 2000.  A red line indicates wolves, starting around (1960, 15) and going up and down slightly on twice, dropping to (1963, 15), then increasing to (1977, 45), down 10, then back up to (1980, 50), then a sharp decrease to (1982, 12), a small spike up, and a steady decline, ending with some evening out around (1993, 10).   A blue line indicates moose, starting around (1960, 60), moving steadily upward to a local maximum at (1973, 1400) , then decreasing to a local minimum at (1981, 800), then moving steadily upward to (1987, 1600), dipping down at (1990, 1200), then steadily back upward, ending the graph at (1993, 1850).

This graph shows a predator-prey cycle for wolves and moose. Explain why the graphs do not resemble the idealized graphs used as models of the predator-prey cycle.

  1. This graph reflects all of the influences on both populations in addition to the predator-prey influences.
  2. This graph reflects all of the influences on both populations, but not the predator-prey influences.
  3. This graph reflects just the influence of predator-prey interactions on both populations.
  4. This graph reflects some of the influences on both populations other than the predator-prey influences.
71.
Suppose a population of lizards becomes divided into two groups on two different islands after a devastating tsunami. No predators of the lizard are present on one island, and on the other island is a fierce predator that uses the lizard as its primary source of food. Assuming both populations encounter similar environments in every other way, and both survive and grow over the next 100 years, how do you predict any of the characteristics of the two lizard populations to differ at the end of that time? Give specific examples to explain your prediction.
  1. The lizards on the island with no predators will likely evolve adaptations such as camouflaged coloration, sharp spines, or toxins to defend against this predator. These adaptations will likely be absent in the other population because they are adapted to other predators.
  2. The lizards that survive the fierce predator will likely evolve adaptations such as camouflaged coloration, sharp spines, or toxins to defend against this predator. These adaptations will likely be absent in the other population because they are adapted to other predators.
  3. The lizards that survive the fierce predator will likely evolve adaptations such as camouflaged coloration, sharp spines, or toxins to defend against this predator. These adaptations will likely be absent in the other population because this predator is not a factor in their survival.
  4. The lizards on the island with no predators will likely evolve adaptations such as camouflaged coloration, sharp spines, or toxins to defend against this predator. These adaptations will likely be absent in the other population because they have survived this predator.
72.
The downy woodpecker and the hairy woodpecker are two species that live in the same habitats. The downy woodpecker is slightly smaller and has a smaller beak than the hairy woodpecker. The downy woodpecker uses its bill to search for food on small twigs and branches while the hairy woodpecker is most often observed searching for food on tree trunks. Explain how the competitive exclusion principle relates to this example.
  1. Both woodpeckers have identical bill structure, but do not access their food from the same places in the habitat. They do not directly compete with one another for food and thus, can coexist in the same habitat.
  2. Both live in the same habitat and have some similarities, but access their food from the same places in the habitat. In this way, the two species can coexist in the same habitat.
  3. Both woodpeckers share similarities in their bill structures. So, they directly compete with one another for food. This directly relates to competitive exclusion principle.
  4. Both live in the same habitat and have some similarities, but do not access their food from the same places in the habitat. In this way, the two species can coexist in the same habitat.
73.
Honey bees are pollinators. Identify the type of symbiotic relationship that exists between honey bees and flowering plants, and explain why your reasoning.
  1. This is commensalism because bees help plants pollinate and, in turn, obtain nectar from the plants.
  2. This is a mutualistic relationship, because bees obtain nectar from the plants, but do not provide any benefits to the plants.
  3. This is commensalism, because bees obtain nectar from the plants, but do not provide any benefits to the plants.
  4. This is a mutualistic relationship, because bees help plants pollinate and, in turn, obtain nectar from the plants.
74.
Prairie dogs are considered a keystone species in the western U.S. because of their extensive burrowing activities and their role as a prey animal. Explain why these characteristics would result in the keystone role of prairie dogs in their ecosystem.
  1. Prairie dogs provide protection and shelter for small animals and harm predator animals in the ecosystem.
  2. Without the prairie dogs, the ecosystem might collapse due to lack of protection and shelter for small animals and lack of prey to sustain large predator animals.
  3. Prairie dogs dig underground burrows, reducing aeration in the soil and preventing excessive growth of plants above ground.
  4. The burrows prairie dogs dig underground provide shelter for other species of animals as well as protection from predators, but prevent growth of plants above ground.
75.

A table where the first column indicates which species of bird was raised by parents of species A, chicks of species A and chicks of species B.  Species A chicks made contact calls to other members of the flock using the species A call. Species B chicks made contact calls to other members of the flock using the species A call. Species A chicks made species A alarm calls in response to predator sightings. Species B chicks made species B alarm calls in response to predator sightings.

Mating pairs of two different species of parrots sometimes lay their eggs in the same nest. When this happens, only one mating pair ends up parenting the chicks even though chicks of both species may be present. The chicks in such mixed nesting groups displayed some interesting behaviors summarized in the table. Classify these behaviors as innate or learned, and explain how they compare.

  1. An alarm call is an innate behavior and a contact call is a learned behavior. Innate behavior comes out automatically in response to a stimulus whereas learned behavior develops over time after observing other birds carrying out the behavior.
  2. The alarm call is a learned behavior and contact call is an innate behavior. Learned behavior develops over time after observing birds carrying out the behavior whereas innate behavior comes out automatically in response to a certain stimulus.
  3. The alarm call is an innate behavior and contact call is a learned behavior. Innate behavior develops over time in response to stimulus after continuous exposure. Learned behavior develops over time after observing other birds carrying out their behavior.
  4. The alarm call is a learned behavior and contact call is an innate behavior. Learned behavior comes out automatically whereas innate behavior develops over time in response to stimulus after continuous exposure.
76.
Mammals such as humans show a behavior known as the flight or fight response. Explain how natural selection was likely involved in the development of this behavior that can be observed in humans today.
  1. Individuals showing fight or flight behavior was more likely to survive than individuals lacking the trait. This trait got randomly selected by natural selection, thus became preferentially incorporated into the human lineage.
  2. Individuals showing fight or flight behavior were more likely to survive than individuals lacking the trait. Sudden, inheritable changes were naturally selected, which included the fight or flight behavior. Thus, this response was incorporated into the human lineage.
  3. Individuals showing fight or flight behavior were more likely to survive than individuals lacking this trait. Therefore surviving individuals passed on their trait to offspring while non-surviving individuals do not. Thus, this response became incorporated into human lineage.
  4. Individuals showing fight or flight behavior were not more fit than individuals lacking this trait. However, the trait was selected by natural selection due to a random chance event in the gene frequency of individuals showing fight or flight behavior.
77.
A researcher studying minnows, a type of fish, kept two groups of 20 fish in separate containers. The containers were linked by a pair of small tubes outfitted with a pump that constantly circulated water between both tanks. The researcher observed both groups of fish after placing a larger fish known to be a predator of minnows into one of the tanks. Fish in both tanks demonstrated alarm behavior. How can you explain these observations?
  1. Fish in the tank that received the predator released alarm signals in chemical form. These compounds circulated and reached the other tank, eliciting an alarm response from the fish there nonetheless.
  2. Fish in the tank that received the predator released alarm signals in the form of electrical signals. These compounds circulated and reached the other tank, eliciting an alarm response from the fish there nonetheless.
  3. The predator introduced in one tank of fish released alarm signals in chemical form. These compounds circulated and reached the other tank, eliciting an alarm response from the fish there nonetheless.
  4. Fish in the tank that did not receive the predator released alarm signals in the chemical form. These compounds circulated and reached the other tank and elicited an alarm response from the fish.
78.
In some species, males expend a lot of energy in courtship rituals, whereas in other species, males expend much less energy in other ways of attracting mates such as producing colorful plumage. What does this mean for any energy that left over males of these species might have to devote to care for offspring?
  1. Males of species carrying out courtship rituals assist in parental care whereas males that use colorful plumage to attract mates do not assist with the parental care.
  2. Males of species carrying out courtship rituals do not assist in parental care whereas males that use colorful plumage to attract mates have energy available to assist with parental care.
  3. Males of species carrying out courtship rituals as well as species of males that use colorful plumage to attract mates, both would assist with the parental care.
  4. Males of species carrying out courtship rituals as well as species of males that use colorful plumage to attract mates would not assist in parental care as the females would be involved.
79.
Female spotted sandpipers fight each other for resource-rich territories on their beach breeding grounds. Based on this, which mating type would most likely be operating in this species? Explain your reasoning.
  1. Polyandrous mating is most likely operating as the females are establishing territories apart from other females. The females will then attract males to the resources they control which will result in many males attracted to few females with the richest territories.
  2. Polygynous mating is most likely operating as the females are establishing territories apart from other females. The females from all territories would attract males to the resources they control, which would result in few males attracted to many females in each territory.
  3. Polyandrous mating is most likely operating as the females are establishing territories apart from other females. The females from all territories would attract males to the resources they control, which would result in few males attracted to many females in each territory.
  4. Polygynous mating is most likely operating as the females are establishing territories apart from other females. The females will then attract males to the resources they control which would result in many males attracted to few females with the richest territories.
80.
Describe Pavlov’s dog experiments as an example of classical conditioning.
  1. Pavlov demonstrated classical conditioning through a maze running experiment with the dog. The motivation for the dog to work its way through the maze was a piece of food at the end of the maze. The dog ran in one trial per day and had food available at the end of the run.
  2. Pavlov hung a chicken piece in a cage too high for the dog to reach and several boxes were placed randomly on the floor. Eventually the dog was able to stack the boxes and climb on top to get the chicken piece through classical conditioning.
  3. Pavlov put a dog in a large box that contained a lever that would dispense food to the dog when pressed. While initially the dog would push the lever a few times by accident, it eventually associated pushing the lever with getting the food through classical conditioning.
  4. Pavlov sounded a bell whenever food was presented to a dog, which produced saliva in response to the sight or smell of the food. Through classical conditioning, the dog started responding to the bell ringing with salivation as the dog came to associate the bell sound with the arrival of food.
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