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Concepts of Biology

Introduction

Concepts of BiologyIntroduction
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Table of contents
  1. Preface
  2. The Cellular Foundation of Life
    1. 1 Introduction to Biology
      1. Introduction
      2. 1.1 Themes and Concepts of Biology
      3. 1.2 The Process of Science
      4. Key Terms
      5. Chapter Summary
      6. Visual Connection Questions
      7. Review Questions
      8. Critical Thinking Questions
    2. 2 Chemistry of Life
      1. Introduction
      2. 2.1 The Building Blocks of Molecules
      3. 2.2 Water
      4. 2.3 Biological Molecules
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    3. 3 Cell Structure and Function
      1. Introduction
      2. 3.1 How Cells Are Studied
      3. 3.2 Comparing Prokaryotic and Eukaryotic Cells
      4. 3.3 Eukaryotic Cells
      5. 3.4 The Cell Membrane
      6. 3.5 Passive Transport
      7. 3.6 Active Transport
      8. Key Terms
      9. Chapter Summary
      10. Visual Connection Questions
      11. Review Questions
      12. Critical Thinking Questions
    4. 4 How Cells Obtain Energy
      1. Introduction
      2. 4.1 Energy and Metabolism
      3. 4.2 Glycolysis
      4. 4.3 Citric Acid Cycle and Oxidative Phosphorylation
      5. 4.4 Fermentation
      6. 4.5 Connections to Other Metabolic Pathways
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    5. 5 Photosynthesis
      1. Introduction
      2. 5.1 Overview of Photosynthesis
      3. 5.2 The Light-Dependent Reactions of Photosynthesis
      4. 5.3 The Calvin Cycle
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  3. Cell Division and Genetics
    1. 6 Reproduction at the Cellular Level
      1. Introduction
      2. 6.1 The Genome
      3. 6.2 The Cell Cycle
      4. 6.3 Cancer and the Cell Cycle
      5. 6.4 Prokaryotic Cell Division
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    2. 7 The Cellular Basis of Inheritance
      1. Introduction
      2. 7.1 Sexual Reproduction
      3. 7.2 Meiosis
      4. 7.3 Variations in Meiosis
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    3. 8 Patterns of Inheritance
      1. Introduction
      2. 8.1 Mendel’s Experiments
      3. 8.2 Laws of Inheritance
      4. 8.3 Extensions of the Laws of Inheritance
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  4. Molecular Biology and Biotechnology
    1. 9 Molecular Biology
      1. Introduction
      2. 9.1 The Structure of DNA
      3. 9.2 DNA Replication
      4. 9.3 Transcription
      5. 9.4 Translation
      6. 9.5 How Genes Are Regulated
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    2. 10 Biotechnology
      1. Introduction
      2. 10.1 Cloning and Genetic Engineering
      3. 10.2 Biotechnology in Medicine and Agriculture
      4. 10.3 Genomics and Proteomics
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  5. Evolution and the Diversity of Life
    1. 11 Evolution and Its Processes
      1. Introduction
      2. 11.1 Discovering How Populations Change
      3. 11.2 Mechanisms of Evolution
      4. 11.3 Evidence of Evolution
      5. 11.4 Speciation
      6. 11.5 Common Misconceptions about Evolution
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    2. 12 Diversity of Life
      1. Introduction
      2. 12.1 Organizing Life on Earth
      3. 12.2 Determining Evolutionary Relationships
      4. Key Terms
      5. Chapter Summary
      6. Visual Connection Questions
      7. Review Questions
      8. Critical Thinking Questions
    3. 13 Diversity of Microbes, Fungi, and Protists
      1. Introduction
      2. 13.1 Prokaryotic Diversity
      3. 13.2 Eukaryotic Origins
      4. 13.3 Protists
      5. 13.4 Fungi
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    4. 14 Diversity of Plants
      1. Introduction
      2. 14.1 The Plant Kingdom
      3. 14.2 Seedless Plants
      4. 14.3 Seed Plants: Gymnosperms
      5. 14.4 Seed Plants: Angiosperms
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    5. 15 Diversity of Animals
      1. Introduction
      2. 15.1 Features of the Animal Kingdom
      3. 15.2 Sponges and Cnidarians
      4. 15.3 Flatworms, Nematodes, and Arthropods
      5. 15.4 Mollusks and Annelids
      6. 15.5 Echinoderms and Chordates
      7. 15.6 Vertebrates
      8. Key Terms
      9. Chapter Summary
      10. Visual Connection Questions
      11. Review Questions
      12. Critical Thinking Questions
  6. Animal Structure and Function
    1. 16 The Body’s Systems
      1. Introduction
      2. 16.1 Homeostasis and Osmoregulation
      3. 16.2 Digestive System
      4. 16.3 Circulatory and Respiratory Systems
      5. 16.4 Endocrine System
      6. 16.5 Musculoskeletal System
      7. 16.6 Nervous System
      8. Key Terms
      9. Chapter Summary
      10. Visual Connection Questions
      11. Review Questions
      12. Critical Thinking Questions
    2. 17 The Immune System and Disease
      1. Introduction
      2. 17.1 Viruses
      3. 17.2 Innate Immunity
      4. 17.3 Adaptive Immunity
      5. 17.4 Disruptions in the Immune System
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    3. 18 Animal Reproduction and Development
      1. Introduction
      2. 18.1 How Animals Reproduce
      3. 18.2 Development and Organogenesis
      4. 18.3 Human Reproduction
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  7. Ecology
    1. 19 Population and Community Ecology
      1. Introduction
      2. 19.1 Population Demographics and Dynamics
      3. 19.2 Population Growth and Regulation
      4. 19.3 The Human Population
      5. 19.4 Community Ecology
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    2. 20 Ecosystems and the Biosphere
      1. Introduction
      2. 20.1 Waterford's Energy Flow through Ecosystems
      3. 20.2 Biogeochemical Cycles
      4. 20.3 Terrestrial Biomes
      5. 20.4 Aquatic and Marine Biomes
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    3. 21 Conservation and Biodiversity
      1. Introduction
      2. 21.1 Importance of Biodiversity
      3. 21.2 Threats to Biodiversity
      4. 21.3 Preserving Biodiversity
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  8. A | The Periodic Table of Elements
  9. B | Geological Time
  10. C | Measurements and the Metric System
  11. Index
Three images are shown. Part a shows a mother and baby hippopotamus. In part b, mature Joshua trees are pictured next to saplings. In part c, a mother and baby flamingo are shown.
Figure 7.1 Each of us, like these other large multicellular organisms, begins life as a fertilized egg. After trillions of cell divisions, each of us develops into a complex, multicellular organism. (credit a: modification of work by Frank Wouters; credit b: modification of work by Ken Cole, USGS; credit c: modification of work by Martin Pettitt)

Chapter Outline

7.1 Sexual Reproduction
7.2 Meiosis
7.3 Variations in Meiosis

The ability to reproduce in kind is a basic characteristic of all living things. In kind means that the offspring of any organism closely resembles its parent or parents. Hippopotamuses give birth to hippopotamus calves; Monterey pine trees produce seeds from which Monterey pine seedlings emerge; and adult flamingos lay eggs that hatch into flamingo chicks. In kind does not generally mean exactly the same. While many single-celled organisms and a few multicellular organisms can produce genetically identical clones of themselves through mitotic cell division, many single-celled organisms and most multicellular organisms reproduce regularly using another method.

Note that, in genetics, "parent" is often used to describe the individual organism(s) that contribute genetic material to an offspring, usually in the form of gamete cells. The concept of a genetic parent is distinct from social and legal concepts of parenthood, and may differ from those whom people consider their parents. Even within the animal kingdom, characteristics that may often be associated with sexual reproduction, such as parental care or sexual behavior, are not universal.

Sexual reproduction is the production of haploid cells and the fusion of a haploid cell from each genetic parent to form a single, unique diploid cell. In multicellular organisms, the new diploid cell will then undergo mitotic cell divisions to develop into an adult organism. A type of cell division called meiosis leads to the haploid cells that are part of the sexual reproductive cycle. Sexual reproduction, specifically meiosis and fertilization, introduces variation into offspring that may account for the evolutionary success of sexual reproduction. The vast majority of eukaryotic organisms can or must employ some form of meiosis and fertilization to reproduce.

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