Microscopes allowed scientists to observe Prokaryotic cells which make up Bacteria and Archaea. These cells are small and contain no membrane- bound organelles. It allowed them to observe Eukaryotic cells with a nucleus and membrane-bound organelles that perform different life functions.
<span>Depletion of the ozone layer. Choloroflourocarbon (CFCS) are dangerous because of their destructive reaction with Ozone particles, which provide the Earth with a protective layer or shield against UV radiation. Depletion of the ozone layer begins when when CFC gets into the stratosphere. Sunlight breaks up cfcs releasing Chlorine Atom. Chlorine atoms in turn react with Ozone, starting a chemical cycle that destroys the ozone layer in that area. Once the ozone layer is depleted, there's nothing holding back the harmful UVB wavelengths of ultraviolet light (UV light) from passing through the Earth's atmosphere causing havoc on plants and animals.</span>
Sweating in response to external stimulus
The biceps and triceps muscles work together to allow you to bend and straighten your elbow. When you want to bend your elbow, your biceps muscle contracts (Figure below), and, at the same time, the triceps muscle relaxes. The biceps is the flexor, and the triceps is the extensor of your elbow joint.