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The Biology of the Immune System: A Scientific Exploration
A primer on the immune system: how innate and adaptive defenses work, how the body tells friend from foe, and why the response sometimes goes too far.
Health and Medicine
Human Biology Explained
How the immune system, brain and body processes work, in plain language.
Discovering the Secrets of the Human Body
See how the body's organ systems cooperate, from climbing a flight of stairs to digesting a meal, and why no system works alone.
Human Evolution: A Scientific Perspective
An overview of hominin evolution, from early upright walkers to modern humans, and how fossils and genetics shape the picture, with dates given as ranges.
The Biology of Addiction: A Scientific Exploration
How the brain reward system works, and how repeated exposure to rewarding substances or behaviors can change tolerance, craving and control, explained in general terms.
The Biology of Aging: A Look into the Aging Process
What happens inside cells and tissues as we age, the main scientific theories of aging, and which questions researchers still consider open.
The Biology of Cancer: A Scientific Exploration
A general primer on how normal cell growth control breaks down, how accumulated genetic changes lead to cancer, and why it is many diseases rather than one.
The Biology of Emotions: A Scientific Exploration
Which brain regions and body signals take part in emotion, and how scientists describe and debate what an emotion actually is.
The Biology of Fertility: A Scientific Exploration
A general look at reproductive biology: the organs and hormones involved, how eggs and sperm meet, and the biological factors that influence conception.
The Biology of Memory: A Scientific Exploration
How the brain encodes, stores and retrieves memories, the role of the hippocampus and synapses, and the biological reasons we forget.
The Biology of the Human Body: A Scientific Exploration
Follow the body's levels of organization from cells to tissues, organs and systems, and learn how homeostasis keeps internal conditions steady.
The Biology of the Human Eye: A Scientific Exploration
A guide to the eye's anatomy, the retina's rods, cones and other cells, and how common vision conditions relate to its structure, in general terms.
The Biology of the Human Heart: A Scientific Exploration
A look at the heart's four chambers, valves, wall structure and blood supply, and how blood flows through it, with a brief note on how the beat is controlled.
The Biology of the Human Microbiome: A Scientific Exploration
Meet the trillions of microbes living in and on the human body, what they seem to do for us, and the questions researchers have not yet answered.
The Physics of The Human Body's Skeletal System: Understanding the Science of Bones and Muscles
A mechanical look at how bones and muscles act as levers, how loads and forces are handled, and a worked example of the force in the biceps.
The Physics of The Human Body's Thermoregulation: Understanding the Science of Body Temperature
How the body balances heat production and heat loss through conduction, convection, radiation and evaporation, and why core temperature is held in a narrow range.
The Physics of The Human Eye: Understanding the Science of Vision
Treat the eye as an optical system: how refraction at the cornea and lens focuses light onto the retina, and why focus errors occur.
The Science of The Human Body: Understanding the Wonders of the Human Form
A newcomer's guide to human anatomy: the standard body position, planes and directional terms, body cavities, and how anatomy differs from physiology.
The Science of The Human Body's Circulatory System: Understanding the Wonders of the Heart and Blood Vessels
Follow blood through arteries, capillaries and veins to see how circulation delivers oxygen and nutrients and carries away waste.
The Science of The Human Body's Digestive System: Understanding the Wonders of the Gut and Gut Bacteria
Walk the digestive tract from mouth to colon, with a clear account of how food is broken down, absorbed and processed at each stage.
The Science of The Human Eye's Vision: Understanding the Wonders of the Visible Spectrum
How rods, cones and the brain turn wavelengths of light into the colors we perceive, and why color vision differs between people.
The Science of The Human Heart: Understanding the Wonders of Our Body's Pump
The electrical signal and pumping cycle behind every heartbeat, what causes the sounds, and what your pulse and resting heart rate reflect.
The Science of The Human Immune System: Understanding the Wonders of Our Body's Defense
Meet the main immune cell types, from neutrophils to T and B cells, and see how antibodies and immune memory fit into innate and adaptive defense.
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