I know there's already a forum for sore and tender scalps but naturally, I can't find it! I needed to register before posting...so it's GONE. For about a year my scalp has been so sore and so tender that it hurts 24 hrs a day. At first I thought perhaps I was allergic to my shampoo so I changed brands. No improvement. Next I wondered if my shower was too hot.
Although small in size, the eye is a very complex organ. The eye is approximately 1 inch (2.54 cm) wide, 1 inch deep and 0.9 inches (2.3 cm) tall. The tough, outermost layer of the eye is called the sclera. It maintains the shape of the eye.
The smallest objects that can be seen by the human eye are about 0.1 mm long. Some single-celled organisms are just big enough that you could see them. A human egg is about 0.12 mm in diameter. The vast majority of cells in your body and cells that form bacteria are too small to see without a microscope. Usually, when a cell gets too large, it divides or stops growing.