FACT: most uses of the word 'FACT' in this thread could be replaced by 'THEORY'.

FACT: The protein hemoglobin, which carries oxygen in the blood, changes shape when it binds oxygen. When it changes shape, it absorbs different wavelengths of light, making it change color. When blood is exposed to air, much more of the hemoglobin absorbs oxygen than had in the vein the blood came from (in the veins, the hemoglobin has already given up most of its oxygen to the body). Therefore, the blood turns red.

The changing shape of Hemoglobin allows it to bind each successive Oxygen pair more efficiently than the last. As each Heme group binds to an Oxygen it puts a strain on the Oxygen-less Heme groups in the other subunits of Hemoglobin and will eventually cause a conformational change in the other subunits that makes Oxygen bind more efficiently. This switch from a Tense state to a relaxed state and back again is the reason Oxygen binds to Hemoglobin with a sigmoid pattern instead of a hyperbolic curve.

As Epsi said....this is a theory that is widely supported by experimental data and the scientific community as a whole.

Fact: There are between 100,000,000,000 and 1,000,000,000,000 stars in a normal galaxy.

Fact: Looking directly at the photosphere of the Sun (the bright disk of the Sun itself), even for just a few seconds, can cause permanent damage to the retina of the eye, because of the intense visible and invisible radiation that the photosphere emits. This damage can result in permanent impairment of vision, up to and including blindness. The retina has no sensitivity to pain, and the effects of retinal damage may not appear for hours, so there is no warning that injury is occurring.

Yeah, but what the hell is Goofy?

An asteroid in about 30 years will come dangerously close to Earth on my BIRTHDAY!!! (Well, it's supposed to)

Bump my favorite thread that I have started.

 Fact: after you die, your still living hand can hypnotize a chicken while you have a massive erection.