Human Body feed
Down to breathe in
When you inhale quietly, your diaphragm contracts and moves downward. That movement enlarges the chest cavity and helps lower pressure inside the lungs relative to outside air. Air then flows inward because of the pressure difference, not because the lungs actively pull with their own muscles.
300
Babies have more separate skeletal pieces than adults, often described as about 300 bones compared with the usual adult count of 206. The newborn number is approximate because developing bone and cartilage are not always counted the same way.
1 cm
People are usually slightly taller after a night lying down because spinal discs regain fluid when unloaded. Around a centimeter is a useful rough illustration, not a fixed daily change for everyone.