frogs in ocean water

Question
well actually I have two but if you can only answer the one then that's okay.
what would happen if you put a frog in ocean water?
and what would happen if you placed a marine jellyfish in freshwater?
I thank you for your time in advance and hope you can help me.  

Answer
Hi,
thank you for your question.
Both animals would die. The reason for this is osmosis: imagine you have a glass of water that is divided into two halves by a fine mesh. Then you put for example food colouring into one half. At first, only this half would assume the coluor, but after a while it would penetrate the mesh and all the water in the glass would have the same colour again. The water "wants" to achieve the same concentration everywhere.

Now, the frog and the ocean are the parts of the glass and the  mesh is the skin of the frog. It allows water to pass. Since the salt concentration in rhe ocean water is so much higher, the water in the frog would be "sucked out", he would more or less dry out, dying from dehydration. That's the reason why saltwater fish actually drink water, they need to compensate for the osmosis that robs them of water.
A jellyfish has a higher salt concentration in its body that fresh water. So water would pass into its body cells, causing them to swell and burst.
Here you can find more information on osmosis:
http://www.purchon.com/biology/osmosis.htm
I hope I was of some help
Jennifer