1. The human body contains 100,000,000,000,000 cells, on average. A bacterial colony can grow to 1,000,000,000 cells overnight.
2. An amoeba (single-celled organism) has more DNA than a human cell.
3. Most humans have half a pound of bacteria in their colons.
4. There are more prokaryotic (bacterial) cells in and on a person than there are human cells.
5. It takes a substance just over half a second to cross a 50 micrometer cell by diffusion. It would take eight years for the same substance to diffuse one meter.
6. Only about 20% of all the genes in our genome (total genes) are expressed in the human brain. Only 10% are expressed in most other cells.
7. It’s estimated that about 100 potentially cancerous cells arise in the body each day. These are caught by cell safety systems and killed.
8. Muscles are contracted by default. The energy we expend is used to extend them.
9. Only two percent of our genome codes for proteins.
10. Human mitochondria (cell organelles) contain their own DNA which is inherited only from the mother and not the father. This DNA is arranged in a genome which appears prokaryotic (as in bacteria) rather than eukaryotic (as in the normal human genome).
11. If uncoiled, the DNA in every human cell would be two meters long.
12. Our medulla stimulates the body to breathe due to the build-up of carbon dioxide – not the lack of oxygen.
13. You’re four to five times more likely to die in a car crash on the way to buy a lottery ticket than you are to win the lottery. So for every one person who wins the lottery, four or five people are dead.
That last one was told to me by my statistics teacher. It may or may not be true, but it’s pretty funny. Be sure to visit the site from which I obtained that picture – they’re trying to figure out all the genes that make people fat.