I'd think that'd be the Myelin Sheath
Answer: the water on or surrounding the surface of the globe, including the water of the oceans and the water in the atmosphere.
Explanation: The hydrosphere includes water that is on the surface of the planet, underground, and in the air. A planet's hydrosphere can be liquid, vapor, or ice. On Earth, liquid water exists on the surface in the form of oceans, lakes and rivers. It also exists below ground—as groundwater, in wells and aquifers.
Using the thick blood film to detect malaria enables observation od parasite morphology and it is used to quantify and identify parasites to the species level. For that kind of detection a high-power microscope (400 times to 1,000 times magnification) is required. The microscopist can look for parasites in a relatively large volume of blood, thus increasing the sensitivity of the test.
