User talk:Abdelrhman.elshazly

Human Body

1-	The human body is a complex, highly organized structure made up of unique cells that work together to accomplish the specific functions necessary for sustaining life.

2-	Cells are the basic building blocks of the body. All tissues and organs are made of billions of different cells. Human cells vary in size, but all are quite small. Even the largest, a fertilized egg, is too small to be seen with the naked eye.

3-	Organs are the body's recognizable structures (for example, the heart, lungs, liver, eyes, and stomach) that perform specific functions. An organ is made of several types of tissue and therefore several types of cells.

https://www.msdmanuals.com/home/fundamentals/the-human-body/tissues-and-organs https://www.britannica.com/science/human-body