La célula humana

The video explains human development from a single cell to a fully formed baby. It begins with the fusion of an egg and sperm to form a zygote, which undergoes multiple cell divisions. As the cells multiply, they differentiate into various types, forming tissues and organs. By 12 weeks, the heart starts beating, and by 20 weeks, features like teeth and nails develop. At birth, the human body consists of 10 trillion cells, illustrating the complexity and growth from a single cell.

What significant changes occur in the body by 20 weeks of development?

How many cells are present in the human body at birth?