Human Body feed
4
The human heart normally has four chambers: two atria that receive blood and two ventricles that pump it onward. The right and left sides serve different circuits, linking the lungs with the rest of the body in a continuous flow.
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.