1. The cracking sound made by knuckles, necks, backs, and other joints when they’re cracked is the sound of bubbles popping in the joints’ fluid. Is it harmful? Not terribly. But cracking a joint too often can hurt the cords, called ligaments, that surround the joint
2. Just one drop of blood contains about 10,000 while blood cells and 250,000 platelets
3. . The Brain is a very wrinkly organ! If you spread it out, your brain would be about the size of a pillowcase. By the time you are six years old, your brain is already 90 percent of the size it will be when you are an adult
4. The liver has an amazing ability to grow back if part of it is removed due to injury, disease, or surgery. It will even grow to be just the right size for the body it’s in.
5. Your salivary glands produce two to six cups of (0.5-1.5 litres) of saliva a day. Six cups of saliva would come close to filling a big, two-litre (67.6) ounce soda bottle!