|
|
In most climates, 8 to 10 glasses of water per day is recommended for adults. The best indicator for adequate fluid intake is frequent, clear urination.
Your skin wrinkles if you stay in the bathtub a long time because the outermost layer of skin (which consists of dead keratin) swells when it absorbs water. It is tightly attached to the skin below it, so it compensates for the increased area by wrinkling. This happens to the hands and feet because they have the thickest layer of dead keratin cells.
The human body produces and destroys 15 million blood cells every second.
It is difficult to obtain enough calcium without consuming milk or other dairy foods.
Acetaminophen (Tylenol) in overdose can seriously damage the liver. It should never be taken by people who use alcohol heavily; it can result in severe liver damage and even a condition requiring a liver transplant.
![A comparison between chromosomes found in a normal human cell and a cancer cell from the same person](https://biology-forums.com/gallery/47/medium_33_25_06_11_10_34_04.jpeg)
![An example of color blindness test. A person with red-green color blindness would not be able to dis](https://biology-forums.com/gallery/47/medium_14755_27_08_12_12_28_10_82021889.jpeg)