Suppose you were trapped on a desert island with no sources of freshwater. should you drink water from the ocean?

No

Explanation:

No

This is because ocean water contain more salt and by drinking a water with too much salt in a desert you will get severely dehydrated.

Dehydration occurs because a salty water will be hypertonic to your body cells. Hypertonic solution contain more solute relative to that in the cell. When a cell is placed in a hypertonic solution it will lose water to its environment by osmosis. This will cause the cells to shrink and may die of dehydration.

No

Explanation:

Find  a way to boil the water, trust me

cells use diffusion to get substances in and out of themselves. that diffusion will occur across the cell membrane or the outer covering of the cell. because we are talking about the surface of the cell, surface area and volume are  important factors here. as a cell increases in size, its surface area and volume increase as well.  we call that the surface area to volume ratio (sa: vol).  but the catch is that  volume increases at a greater rate than surface  area. in other words, as a cell gets bigger, the sa: vol gets smaller. so a really small cell like bacteria is mostly cell membrane (surface) with very little contents (volume). a really big cell like an egg, is mostly insides with a super thin membrane. so what ends up happening is that the cell cannot efficiently diffuse all of the stuff it needs in/out to survive. therefore cell size is limited to about 100mm. so how do we make organisms bigger than 100mm? cells divide! by dividing and becoming multicellular, organisms are able to grow!   check out the diagrams i attached to see the effect of sa: vol. i hope this ! good luck!