Your belly button, or navel, is a scar where your umbilical cord once was. The tubelike cord connected you to your mother when you were inside her uterus, growing into a baby. It carried oxygen and nourishment to you from the placenta, an organ that develops in the uterus during pregnancy, connecting you to your mother’s blood supply. (It also carried away waste products from your blood.) Once you were born, the umbilical cord was no longer needed, because you began to breathe and eat on your own. The cord was clamped off and cut, and what was left of it withered and dropped off about a week after your birth. Doctors clamp the cord and cut it, leaving a remnant two to three inches long that eventually shrivels up and falls away. Skin grows over the area, and it then becomes the belly button shape you have for life.
- Why is the skin between my toes sometimes red and itchy?
- Will a wart go away if I wrap it in duct tape?
- What is a seed drill?
- My grandmother has a lump on her chin that sprouts hair. What is this?
- Why doesn’t it hurt to cut my hair?
- Why do my fingers get all pruney in the bathtub?
- How does the body cool off?
- Why do some people have freckles?
- Why do people have different color skin?
- Which hair grows the fastest?
- How many hairs do I have on my head?
- What is pus?
- Why do scabs form?
- Who invented the earliest milking machines?
- What causes a bruise?
- Which is the body’s biggest organ?
- How much air does a person breathe in a lifetime?
- Are the lungs connected to my voice?
- How do people breathe in and out?
- Does the brain feel pain?
