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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
43.
Due to global climate change and pollution, a lake experiences changes in temperature and pH. The lake has many species, including sexually reproducing frogs, water fleas that multiply by parthenogenesis, hydra that multiply by budding, and sponges that multiply by fragmentation. Which of these species will most likely survive the changing conditions of the lake?
  1. hydra
  2. sponges
  3. water fleas
  4. sexually-reproducing frogs
44.
Why is sexual reproduction useful when only half the individuals reproduce and two cells must combine to form a new cell?
  1. It completes in a very short period of time.
  2. It results in the rapid production of many offspring.
  3. It increases genetic diversity, allowing organisms to survive in an unpredictable environment.
  4. It requires less energy and leads to genetic variation in the offspring.
45.
Sex determination in humans and other mammals is dictated by the presence of sex chromosomes. Are there different factors that determine the sex of other types of animals?
  1. No, the sex of an individual is only determined by the presence of sex chromosomes.
  2. Yes, temperature also determines the sex of an individual.
  3. Yes, humidity and temperature determine the sex of an individual.
  4. Yes, pH and humidity determine the sex of an individual.
46.
What are some advantages of internal compared with external fertilization?
  1. Internal fertilization leads to more genetic variations and increases the survival rates of offsprings.
  2. Internal fertilization increases the survival rates of offspring, and large numbers of offspring are produced.
  3. Internal fertilization increases the survival rates of offspring, and the chance of fertilization with a specific partner also increases.
  4. Internal fertilization increases the survival rates of offspring and decreases the chance of fertilization with a specific partner.
47.
What are the mechanisms that protect and nurture the embryo in oviparous animals?
  1. The hard leathery exterior of bird eggs and the hard calcium covering of reptile eggs provides protection to the growing embryo. Nourishment is provided by yolk in the eggs.
  2. The hard leathery exterior of reptile eggs and the hard calcium covering of bird eggs provide protection to the growing embryo. Nourishment is provided by endosperm in the eggs.
  3. The hard leathery exterior of reptile eggs and the hard calcium covering of bird eggs provide protection to the growing embryo. Nourishment is provided by placenta in the eggs.
  4. The hard leathery exterior of reptile eggs and the hard calcium covering of bird eggs provide protection to the growing embryo. Nourishment is provided by yolk in the eggs.
48.
Compare the specialization of reproductive structures found in different types of land animals.
  1. In birds, an opening called the cloaca is used to transfer sperm, whereas in mammals, the presence of the penis and vagina allows direct delivery. Complete reproductive systems are formed in insects, with eggs maturing in the testes and sperm maturing in the ovaries.
  2. In birds, an opening called the cloaca is used to transfer sperm, whereas in mammals, the presence of the penis and vagina allows direct delivery. Complete reproductive systems are formed in insects, with eggs maturing in the ovaries and sperm maturing in the testes.
  3. In birds, sperm are transferred via the spermatheca, whereas in mammals, the presence of the penis and vagina allows direct delivery. Complete reproductive systems are formed in insects, with eggs maturing in the ovaries and sperm maturing in the testes.
  4. In birds, an opening called the cloaca is used to transfer sperm, whereas in mammals, the presence of the penis and vagina allows direct delivery. Insects always use parthenogenesis.
49.
Explain the fate of the newly released secondary oocyte after ovulation.
  1. If it fuses with a sperm, the resulting zygote enters the cervix for implantation. If it is not fertilized, it will return to the oviduct.
  2. If it fuses with a sperm, the resulting zygote enters the uterus for implantation. If it is not fertilized, it will return to oviduct.
  3. If it fuses with a sperm, the resulting zygote enters the uterus for implantation. If it is not fertilized, it will degrade and exit the body.
  4. If it fuses with a sperm, the resulting zygote enters the cervix for implantation. If it is not fertilized, it will degrade and exit the body.
50.
Explain the similarities and differences in sexual response in males and females.
  1. Both males and females show specific arousal, but the sexual response differs in intensity and duration.
  2. Both males and females show specific arousal. In males, breathing rate and heart rate are increased. In females, there is a decrease in breathing rate and heart rate.
  3. Vasodilation occurs in both males and females, allowing blood to engorge erectile tissue in the nipples, clitoris, labia, vagina, and penis. In males, breathing rate and heart rate are increased. In females, there is a decrease in breathing rate and heart rate.
  4. Both males and females show an increase in heart rate, breathing rate, and blood pressure during phase one and phase two. However, sexual response differs in intensity and duration in males and females. Also, males show specific arousal, while females show non-specific arousal.
51.
Compare and contrast spermatogenesis and oogenesis.
  1. Both are the form of gametogenesis that takes place through mitosis. Spermatogenesis is the process of formation of four sperm in the testes in males. The process of formation of one ovum in the ovaries in females is called oogenesis.
  2. Both are the form of gametogenesis that takes place through meiosis. Spermatogenesis is the process of formation of four sperm in the testes in males. The process of formation of four ova in the ovaries in females is called oogenesis.
  3. Bothare the form of gametogenesis that takes place through meiosis. Spermatogenesis is the process of formation of four sperm in the testes in males. The process of formation of one ovum in the ovaries in females is called oogenesis.
  4. Both are the form of gametogenesis that takes place through meiosis. Spermatogenesis is the process of formation of one sperm in the testes in males, while the process of formation of one ovum in the ovaries in females is called oogenesis.
52.
How does the hypothalamus regulate the secretion of reproductive hormones in males?
  1. The hypothalamus releases FSH and LH at puberty by secreting of GnRH. FSH stimulates the Leydig cells in the testes and LH stimulates the Sertoli cells to synthesize and secrete testosterone.
  2. The hypothalamus releases FSH and LH at puberty by the secretion of GHRH. FSH stimulates the Sertoli cells in the testes and LH stimulates the Leydig cells to synthesize and secrete testosterone.
  3. The hypothalamus stimulates the release of FSH and LH at puberty by secreting of GnRH. FSH stimulates the Sertoli cells in the testes and LH stimulates the Leydig cells to synthesize and secrete testosterone.
  4. The hypothalamus releases TSH and LH at puberty by the secretion of GnRH. TSH stimulates the Sertoli cells in the testes and LH stimulates the Leydig cells to synthesize and secrete testosterone.
53.
What are the events that take place in a non-pregnant woman after ovulation?
  1. Because a fertilized egg is not implanted into the uterus in a non-pregnant woman, the corpus luteum degenerates, and the levels of estrogen and progesterone decrease. The endometrium begins to degenerate as the progesterone level drops, initiating the next menstrual cycle.
  2. Because a fertilized egg is not implanted into the uterus in a non-pregnant woman, the corpus luteum degenerates, and the levels of estrogen and progesterone increase. The endometrium begins to degenerate as the estrogen level increases, initiating the next menstrual cycle.
  3. Because a fertilized egg is not implanted into the uterus in a non-pregnant woman, the corpus luteum degenerates and the levels of estrogen and progesterone increase. The endometrium begins to degenerate as the progesterone level rises, initiating the next menstrual cycle.
  4. Because a fertilized egg is not implanted into the uterus in a non-pregnant woman, the corpus luteum degenerates and the levels of estrogen and progesterone decrease. The myometrium begins to degenerate as the progesterone level drops, initiating the next menstrual cycle.
54.
The side effects of menopause can be diminished by hormone replacement therapy (HRT). However, many doctors are hesitant to recommend it. What are the possible reasons for this?
  1. Its negative side effects, which include increased risk of colon cancer, osteoporosis, heart disease, macular degeneration, and possibly depression
  2. Its negative side effects, which include increased risk of stroke or heart attack, blood clots, breast cancer, ovarian cancer, endometrial cancer, gall bladder disease, and possibly depression.
  3. Its negative side effects, which include increased risk of stroke or heart attack, blood clots, breast cancer, colon cancer, endometrial cancer, gall bladder disease, and possibly dementia.
  4. Its negative side effects, which include increased risk of stroke or heart attack, blood clots, breast cancer, ovarian cancer, endometrial cancer, gall bladder disease and possibly dementia.
55.
If multiple sperm were to combine with an egg, what would be the outcome?
  1. A cortical reaction would occur if multiple sperm combine with an egg, resulting in a genetically inviable embryo.
  2. The embryo would be genetically inviable and would die in a few days. The zygote might have multiple sets of chromosomes.
  3. The zygote might possess multiple sets of chromosomes, which will result in a neural tube defect in the developing fetus.
  4. The zygote would be viable, but the resulting embryo would be genetically inviable.
56.
After the blastula is formed, where do the embryonic stem cells and germ layers originate?
  1. The inner cell mass contains embryonic stem cells, which arrange themselves into the three germ layers.
  2. The trophoblast in the blastula contains embryonic stem cells, which arrange themselves into three germ layers.
  3. The inner cell mass contains embryonic stem cells, whereas the germ cells originate from the trophoblast.
  4. The embryonic stem cells and germ layers originate from the blastocoel present inside the blastula.
57.
What determines whether a zygote will undergo total or partial cleavage?
  1. Total cleavage takes place in eggs having a large amount of yolk, whereas partial cleavage occurs in eggs having very little or no yolk.
  2. Total cleavage occurs when eggs possess equal concentration of yolk at both poles, whereas partial cleavage occurs when the yolk is not equally distributed.
  3. Total cleavage takes place in eggs having little or no yolk, whereas partial cleavage occurs in eggs having a large amount of yolk.
  4. Total cleavage occurs when divisions of the blastomeres are separate, whereas partial cleavage occurs when blastomeres stay partially connected.
58.
During organogenesis, the ectoderm forms the neural cells and the epidermal cells. How do the ectoderm cells determine which type of cells to form?
  1. Growth factors signal some of the ectodermal cells to form epidermal cells, and the remaining cells form the neural plate.
  2. The notochord cells of the mesoderm signal the ectodermal cells to form epidermal cells as well as the neural plate.
  3. Growth factors signal some of the ectodermal cells to form epidermal cells, and the remaining cells form neural crest cells.
  4. Proteins involved in the Wnt signaling pathway signal the ectodermal cells to form the epidermal cells and the neural plate.
59.
What will be the outcome if the axis is not formed during the developmental stages?
  1. The animal will possess two notochords and may not have a dorsal-ventral or anterior-posterior side.
  2. The animal will lack an anterior-posterior or dorsal-ventral side and may not have complete differentiation of cell layers.
  3. The animal will lack an anterior-posterior or lateral-medial side and may not have complete differentiation of cell layers.
  4. The animal will have incorrect positioning of the dorsal-ventral and lateral-medial sides and differentiation of cell layers will be incomplete.
60.
Explain what the mesoderm is and what it eventually differentiates into.
  1. The mesoderm, located on either side of the vertebrate neural tube, develops into various connective tissues. It is reorganized into groups of cells called somites, which develop into facial cartilage, ribs, and lungs.
  2. The mesoderm, located at the border of the neural plate and the non-neural ectoderm, develops into various connective tissues such as the ribs, lungs, segmental muscle, and the notochord, which forms the central axis of the animal body.
  3. The mesoderm, located on either side of the vertebrate neural tube, develops into various connective tissues. It is reorganized into groups of cells called somites, which develop into ribs, lungs, segmental muscle, and the notochord.
  4. The mesoderm, located at the border of the neural plate and the non-neural ectoderm, develops into various connective tissues such as the facial cartilage, ribs, and lungs.
61.
Which best describes the three stages of labor?
  1. During stage one, the cervix thins. During stage two, the cervix is dilated to about 10 cm and the baby is expelled from the uterus. The last stage is the passage of the placenta after the baby has been born.
  2. During stage one, the cervix thins and is dilated to about 10 cm. During stage two, the baby is expelled from the uterus. The last stage is the passage of the placenta after the baby has been born.
  3. During stage one, the cervix thins. During stage two, the cervix is dilated to about 10 cm. During the last stage, the baby is expelled from the uterus, followed by the placenta.
  4. During stage one, the cervix thins and may or may not be dilated. During stage two, the baby is expelled from the uterus. The last stage is the passage of the placenta after the baby has been born.
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