A molecule is the smallest particle in a chemical element or compound that has the chemical properties of that element or compound. Molecules are made up of atom s that are held together by chemical bonds.
Some studies have shown that your deep sleep should at least be 20% of your overall sleep. It means that since most adults need 8-9 hours of sleep, they will need about 1.6-1.8 hours of deep sleep to feel fully functional next day. However, the time of deep sleep is changed and that's mainly due to the change in the sleep need of different group of people. For instance: Age Group.
Only a quarter of the time that your cats spend sleeping is actually when they are in a deep sleep. This is true for younger cats at least, as older cats may spend more like 30 to 40% in a deep sleep. Typically, if your cat is curled up in deep sleep with twitching paws or whiskers, they are dreaming .