about how many cells are in the human body
Human body. The human body is the entire structure of a human being. It is composed of many different types of cells that together create tissues and subsequently organ systems. They ensure homeostasis and the viability of the human body. It comprises a head, neck, trunk (which includes the thorax and abdomen), arms and hands, legs and feet. In the article on red blood cells, it is claimed that there are 20 - 30 trillion red blood cells alone (http://en.wikipedia.org/wiki/Red...), which make up one quarter of all cells in a human body, leading to an estimate of 80 - 120 trillion total cells. New counts revise a popular factoid about how many bacteria live inside us. View Images. You may have heard that there are ten microbial cells in your body for every one of yours—and it turns out you might have heard wrong. Your body is a microbial melting pot, home to trillions of bacteria that help keep you healthy and regular. Scientists concluded that the average human body contains approximately 37.2 trillion cells! Of course, your body will have more or fewer cells than that total, depending upon how your size compares to the average human being, but that's a good starting point for estimating the number of cells in your own body. First, they defined the average human to be a 30 year-old male, 1.72 metres tall, weighing 70 kg, and with a surface area of 1.85 square metres. They then looked at individual organs or cell types in the body, and worked out how many cells were present — and then, just added up the numbers. ^ to top. Going back over the last two centuries, the estimates for the number of cells in the human body have been in the trillions. How many trillions? Anywhere between five trillion, and 200 million trillion! An estimate that has a range between 200 million down to just five is perhaps a little too loose to be of any use. In humans, there are about 200 different types of cells, and within these cells there are about 20 different types of structures or organelles. All cells have a membrane. Cell membranes are the outer layers that hold the cell together. They let nutrients pass into the cell and waste products pass out. In a new study posted ahead of publication on the bioRxiv website, three scientists led by the Weizmann Institute of Science’s Ron Milo find that the average human male is made of 30 trillion cells and contains about 40 trillion bacteria, most of which reside in his digestive tract. The length of a cell’s life can vary. For example, white blood cells live for about thirteen days, cells in the top layer of your skin live about 30 days, red blood cells live for about 120 days, and liver cells live about 18 months. New counts revise a popular factoid about how many bacteria live inside us. You may have heard that there are ten microbial cells in your body for every one of yours—and it turns out you might have heard wrong. Your body is a microbial melting pot, home to trillions of bacteria that help keep you healthy and regular.
37.2 trillion