An introductory biology course

Welcome to Mr. Ehinger’s Biology! On this site, you will (eventually) find a complete introductory course in biology. This course will most probably not fit exactly with your specific syllabus, but if you follow this video course, you will still recieve a solid foundation in biology, from the cell and the fundamentals of life to the human body and its function.

How to use these videos

Now, about these videos. You really shouldn’t just watch and enjoy them. If you really want to learn, you must use a pen and paper too. Take notes from everything written on the screen and copy the simple drawings too. You will see that these kinds of notes and drawings are exactly what you will be required to produce on your exams. So, by taking notes from these videos, you prepare yourself for your exams.

Questions? Feedback?

If you have any questions or feedback, please feel free to post them in the comments section of each video. I can’t promise that I will always answer every question, but I will do my very best. 

Once again, welcome to the wonderful world of biology!

Table of contents

• Home
• Biology videos
  • 1. The Fundamentals of Life
    • 1.1. What is Biology?
    • 1.2. Cell Theory
    • 1.3. How Organisms Acquire Carbon and Energy
    • 1.4. Three Types of Cells
  • 2. Cellular Structure and Function
    • 2.1. The Bacterial Cell
    • 2.2. The Eukaryotic Cell
    • 2.3. The Cellular Membrane
    • 2.4. The Endomembrane System
    • 2.5. The Cytoskeleton. Flagella and Cilia
    • 2.6. Diffusion over Membranes
    • 2.7. Endo- and Exocytosis
    • 2.8. Cellular Respiration
  • 3. Cellular Genetics
    • 3.1. DNA: Structure and Function
    • 3.2. Transcription
    • 3.3. RNA Maturation
    • 3.4. Translation
    • 3.5. Transcriptional Regulation
    • 3.6. DNA Replication
    • 3.7. Mitosis
    • 3.8. Meiosis
  • 4. Mendelian Genetics
    • 4.1. Monohybrid Cross
    • 4.2. Dihybrid Cross
    • 4.3. Genetic Linkage
    • 4.4. Intermediate and Codominant Inheritance
    • 4.5. Sex-linked Inheritance
    • 4.6. Recessive Autosomal Diseases
    • 4.7. Dominant Autosomal Diseases
    • 4.8. Population Genetics
    • 4.9. The Possibilities with Genetics
  • 5. Evolution and Systematics
    • 5.1. Roadmap to a Theory of Evolution
    • 5.2. The Pillars of Evolution
    • 5.3. Evidence for Evolution
    • 5.4. Convergent and Divergent Evolution
    • 5.5. Coevolution
    • 5.6. Stabilizing and Disruptive Selection
    • 5.7. Speciation
    • 5.8. How to Build a Family Tree
    • 5.9. The History of Life
    • 5.10. The Formation of Life
    • 5.11. The Divisions of Life
    • 5.12. Plant Systematics
    • 5.13. Animal Systematics
    • 5.14. Chordate Systematics
    • 5.15. Human Evolution
  • 6. Ethology and Behavioural Ecology
    • 6.1. Genes and Behaviour
    • 6.2. Fundamental Ethological Concepts
    • 6.3. Learning
    • 6.4. Communication
    • 6.5. Animal Coloration
    • 6.6. Behaviour of the Plants
    • 6.7. ESS and Social Organisation
    • 6.8. Sexual Systems
  • 7. Ecology: Systems of Organisms
    • 7.1. Ecosystems
    • 7.2. Nutritional Chains and Food Webs
    • 7.3. Flow of Energy in an Ecosystem
    • 7.4. The Water Cycle
    • 7.5. The Carbon Cycle
    • 7.6. The Nitrogen Cycle
    • 7.7. The Phosphorous Cycle
    • 7.8. Populations: Size and Growth
    • 7.9. Communities. Living Together
    • 7.10. Ecological Succession
    • 7.11. From Bedrock to Litter
    • 7.12. The Lakes
    • 7.13. The Oceans and Seas
    • 7.14. Climate and Biomes
  • 8. Environmental Science
    • 8.1. The Air we Breathe
    • 8.2. Pollution
    • 8.3. Ecosystem Services
    • 8.4. Biodiversity
  • 9. Viruses and Biotechnology
    • 9.1. Viruses
    • 9.2. Antibiotic Resistance
    • 9.3. Biotechnology
    • 9.4. Genetically Modified Organisms
    • 9.5. Stem Cells and Other Cell Lines
  • 10. Plant & Fungal Physiology
    • 10.1. The Organs of the Plants
    • 10.2. Plants With and Without Seeds
    • 10.3. The Root. How the Plant Absorbs Water and Nutrients
    • 10.4. The Trunk and Water Transport
    • 10.5. Structure and Function of the Leaf
    • 10.6. Photosynthesis
    • 10.7. How Plants Grow
    • 10.8. How Plants Reproduce
    • 10.9. Classification of the Fungi
    • 10.10. How Fungi Reproduce
    • 10.11. Fungal Parasites and Pathogens
  • 11. Human Physiology
    • 11.1. Physiology Basics
      • 11.1.1. Three Layers of Cells
      • 11.1.2. Tissues, Organs, and Systems of Organs
      • 11.1.3. Homeostasis
    • 11.2. The Nervous System
      • 11.2.1. The Nervous System in Different Organisms
      • 11.2.2. The Parts of the Nervous System
      • 11.2.3. The Anatomy of the Nerve Cell
      • 11.2.4. The Function of the Nerve Cell
      • 11.2.5. Anatomy and Function of the Central Nervous System
      • 11.2.6. Memory and Sleep
    • 11.3. The Senses
      • 11.3.1. Vision
      • 11.3.2. Hearing and Balance
      • 11.3.3. Taste and Smell
      • 11.3.4. Skin, Sensibility, and Deep Sensibility
    • 11.4. The Endocrine System
      • 11.4.1. The Endocrine System. Different Types of Hormones
      • 11.4.2. How Hormones Work
      • 11.4.3. Some Endocrine Glands
    • 11.5. Food and Digestion
      • 11.5.1. What you Need to Eat
      • 11.5.2. The Food in the Mouth and Throat
      • 11.5.3. The Stomach
      • 11.5.4. The Small Intestine
      • 11.5.5. The Colon and the Rectum
    • 11.6. The Locomotor System
      • 11.6.1. The Structure and Function of Muscles
      • 11.6.2. Skeleton and Joints
      • 11.6.3. Damages to the Locomotor System
    • 11.7. Gas Exchange and Circulation
      • 11.7.1. Respirational Systems
      • 11.7.2. Human Respiration
      • 11.7.3. Circulation in Different Animals
      • 11.7.4. The Human Circulatory System. Heart, Blood Vessels and Blood Pressure
      • 11.7.5. Activity in the Capillaries
      • 11.7.6. Blood Constituents
      • 11.7.7. Blood Groups
      • 11.7.8. Coagulation
      • 11.7.9. Some Blood Diseases
      • 11.7.10. Water Balance. Kidneys
    • 11.8. The Immune System
      • 11.8.1. The First and Second Line of Defense
      • 11.8.2. The Third line of Defense. Adaptive Immunity
      • 11.8.3. Immunological Diseases
    • 11.9. Sex, Love, and STDs
      • 11.9.1. The Male and Female Reproductive Organs
      • 11.9.2. The Menstrual Cycle
      • 11.9.3. Pregnancy
      • 11.9.4. Birth Control
      • 11.9.5. The Chemistry of Love
      • 11.9.6. STDs
      • 11.9.7. Sex on Equal Terms
      • 11.9.8. The End of the Life
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