Holt McDougal Modern Biology: Online Textbook Help

  • Course type: Self-paced
  • Available Lessons: 386
  • Average Lesson Length: 8 min
  • New lessons are still being added
  • Watch a preview:

    Biology: The Study of Life
    chapter 1 / lesson 1
    Biology: The Study of Life

  • Holt McDougal Modern Biology: Online Textbook Help Practice Test

Course Summary

Expand upon the topics covered in your Holt McDougal Modern Biology textbook with our flexible and mobile-friendly textbook companion course. Our easy-to-follow video and text lessons align with the chapters in your book so you can review the tougher subjects with ease and get a better grade in class.
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50 chapters in Holt McDougal Modern Biology: Online Textbook Help

Course Practice Test

Check your knowledge of this course with a 50-question practice test.
  • Comprehensive test covering all topics
  • Detailed video explanations for wrong answers
Week {{::cp.getGoalWeekForTopic(9, 50)}}
Course Progress Best Score
Lesson 1 - DNA: Discovery, Facts, Structure & Function in Heredity  Take Quiz
Lesson 2 - DNA: Chemical Structure of Nucleic Acids & Phosphodiester Bonds  Take Quiz
Lesson 3 - DNA: Adenine, Guanine, Cytosine, Thymine & Complementary Base Pairing  Take Quiz
Lesson 4 - What Is DNA Replication? - Conservative, Semi-Conservative & Dispersive Models  Take Quiz
Lesson 5 - How Helicase Unwinds the DNA Double Helix in Preparation for Replication  Take Quiz
Lesson 6 - How DNA Polymerase and RNA Primase Initiate DNA Replication  Take Quiz
Lesson 7 - DNA Replication: The Leading Strand and DNA Polymerase Activities  Take Quiz
Lesson 8 - DNA Replication: Review of Enzymes, Replication Bubbles & Leading and Lagging Strands  Take Quiz
Lesson 9 - Protein Synthesis in the Cell and the Central Dogma  Take Quiz
Lesson 10 - Transcription of Messenger RNA (mRNA) from DNA  Take Quiz
Lesson 11 - What Is the Genetic Code That Translates RNA Into Amino Acids?  Take Quiz
Lesson 12 - Making Sense of the Genetic Code: Codon Recognition  Take Quiz
Lesson 13 - Codon Recognition: How tRNA and Anticodons Interpret the Genetic Code  Take Quiz
Lesson 14 - The Role of Ribosomes and Peptide Bonds in Genetic Translation  Take Quiz
Lesson 15 - Translation of mRNA to Protein: Initiation, Elongation & Termination Steps  Take Quiz
Week {{::cp.getGoalWeekForTopic(21, 50)}}
Course Progress Best Score
Lesson 1 - The Four Spheres of Earth: Geosphere, Hydrosphere, Biosphere, and Atmosphere  Take Quiz
Lesson 2 - Interactions of Earth's Spheres: Purpose and Examples  Take Quiz
Lesson 3 - What is Biodiversity? - Definition and Relation to Ecosystem Stability  Take Quiz
Lesson 4 - The Ozone Layer: Importance and the Harmful Effects of Thinning  Take Quiz
Lesson 5 - Greenhouse Gases and the Enhanced Greenhouse Effect  Take Quiz
Lesson 6 - Global Warming: Atmospheric Causes and Effect on Climate  Take Quiz
Lesson 7 - Magnification of Toxicants: Persistence, Bioaccumulation & Biological  Take Quiz
Lesson 8 - Acid Deposition: Definition, Causes & Effects  Take Quiz
Lesson 9 - What Is an Invasive Species? - Definition, List & Effects  Take Quiz
Lesson 10 - Environmental Sustainability: Definition and Application  Take Quiz
Lesson 11 - Human Behaviors that Threaten Environmental Sustainability  Take Quiz
Lesson 12 - Pollution and Habitat Destruction: The Human Factors Contributing To Endangerment & Extinction  Take Quiz
Lesson 13 - What Is Conservation Biology? - Definition & Principles  Take Quiz
Lesson 14 - Ecology Restoration: Foundations, Projects and Goals  Take Quiz
Lesson 15 - Land Conservation: Preserving and Restoring Ecosystems  Take Quiz
Lesson 16 - The Endangered Species Act & The World Conservation Strategy: Goals & Purposes  Take Quiz
Week {{::cp.getGoalWeekForTopic(22, 50)}}
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Course Progress Best Score
Lesson 1 - Male Reproductive System: Functions, Organs & Anatomy  Take Quiz
Lesson 2 - Male Reproductive System: Accessory Gland Functions  Take Quiz
Lesson 3 - Testicular Anatomy: Structure, Terms & Diagrams  Take Quiz
Lesson 4 - Male Reproductive System: External Anatomy  Take Quiz
Lesson 5 - Sperm's Journey from the Testes to Urethral Orifice  Take Quiz
Lesson 6 - Female Reproductive System: Internal Anatomy  Take Quiz
Lesson 7 - External Anatomy of the Female Reproductive System  Take Quiz
Lesson 8 - Phases of The Ovarian Cycle: Overview from Puberty to Menopause  Take Quiz
Lesson 9 - Follicular Phase of the Ovarian Cycle  Take Quiz
Lesson 10 - Luteal Phase of the Ovarian Cycle  Take Quiz
Lesson 11 - The Uterine Cycle: Phases and Endometrial Changes  Take Quiz
Lesson 12 - Fertilization and Zygote Formation: Definition and Processes  Take Quiz
Lesson 13 - Early Embryonic Development: The Morula and Blastula  Take Quiz
Lesson 14 - Embryo Implantation and Placenta Formation  Take Quiz
Lesson 15 - The Placenta and the Fetus: Structure and Function  Take Quiz
Lesson 16 - Amniotic Fluid, The Amnion, and the Yolk Sac  Take Quiz
Lesson 17 - Gastrulation and the 3 Germ Layers (Ectoderm, Endoderm & Mesoderm)  Take Quiz
Lesson 18 - Fetal Development in the First Trimester: Stages & Timeline  Take Quiz
Lesson 19 - Second Trimester Fetal Development  Take Quiz
Lesson 20 - Third Trimester Fetal Development  Take Quiz
Lesson 21 - Childbirth: The Role of Hormones in Labor and Delivery  Take Quiz

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