He study of cells has been limited by their small size, and so they were not seen and described until 1665, when robert hooke first looked at dead cells from an oak tree. his contemporary, anton van leeuwenhoek, crafted lenses; and with the improvements in optical aids, a new world was opened. magnification and resolving power limit what can be seen. explain the difference.

Magnification is the ability to see an object that is small at a larger size. This is useful in looking at microscopic objects; however, magnification is of no use without proper resolving power.

The resolving power of a device is its ability to distinguish between to closely placed points. The greater the resolving power, the more distinguishable the points are. This results in clear magnified images, which are easier to understand.

The salt in the sea water dehydrated the sailor because her body could not take in the amount to salt in the sea water