by Human Body Explained: Clear Journeys Through How We Work
Light reflects from a red cup and enters your eyes. Less than a second later, you experience shape, color, depth, and location. Yet there is no tiny red cup inside your head. Inside this episode: - Light Carries A Pattern - The Cornea Does Most Of The Bending - The Pupil And Iris - The Lens Adjusts Focus - The Retina Sources include the references linked below. Sources and further reading: - [National Eye Institute, How the Eyes Work](https://www.nei.nih.gov/eye-health-information/healthy-vision/how-eyes-work) This episode provides general education about how the body works. It is not medical advice, diagnosis, treatment, or a substitute for professional care. Follow Human Body Explained for more clear journeys through how we work.
The moment after you swallow, a carefully timed sequence takes over. Muscles close one route, open another, and push food through a tube even if you are lying down. Over the next several hours, physical movement and chemistry turn a meal into material small enough to cross into the body. Inside this episode: - Before The Swallow - Choosing The Right Path - Moving Through The Esophagus - The Stomach Mixes - Help From Other Organs Sources include the references linked below. Sources and further reading: - [National Institute of Diabetes and Digestive and Kidney Diseases, Your Digestive System and How It Works](https://www.niddk.nih.gov/health-information/digestive-diseases/digestive-system-how-it-works) This episode provides general education about how the body works. It is not medical advice, diagnosis, treatment, or a substitute for professional care. Follow Human Body Explained for more clear journeys through how we work.
Blood leaving your foot does not travel straight back to the foot. It returns to the right side of the heart, visits the lungs, enters the left side, and begins another trip through the body. The heart keeps this circuit moving with 4 chambers, 4 valves, and a rhythm generated inside the heart itself. Inside this episode: - Two Pumps Together - Returning From The Body - The Trip To The Lungs - Returning With Oxygen - Arteries To Capillaries Sources include the references linked below. Sources and further reading: - [National Heart, Lung, and Blood Institute, How the Heart Works](https://www.nhlbi.nih.gov/health/heart) - [National Heart, Lung, and Blood Institute, How Blood Flows Through the Heart](https://www.nhlbi.nih.gov/health/heart/blood-flow) - [National Heart, Lung, and Blood Institute, How the Heart Beats](https://www.nhlbi.nih.gov/health/heart/heart-beats) This episode provides general education about how the body works. It is not medical advice, diagnosis, treatment, or a substitute for professional care. Follow Human Body Explained for more clear journeys through how we work.
Take an ordinary breath, and air crosses a remarkable border. Oxygen moves from the outside world into your blood, while carbon dioxide moves toward the exit. The exchange happens across a surface folded deep inside your chest, where air and blood come within a tiny distance of each other. Inside this episode: - Making Room - The First Passage - The Branching Tree - The Air Sacs - Oxygen Crosses Sources include the references linked below. Sources and further reading: - [National Heart, Lung, and Blood Institute, How the Lungs Work](https://www.nhlbi.nih.gov/health/lungs) - [National Heart, Lung, and Blood Institute, What Breathing Does for the Body](https://www.nhlbi.nih.gov/health/lungs/breathing-benefits) This episode provides general education about how the body works. It is not medical advice, diagnosis, treatment, or a substitute for professional care. Follow Human Body Explained for more clear journeys through how we work.