I need help. I cannot find an answer to this in my book.
What would happen to a frog placed in seawater?
What would happen to a sea cucumber put in fresh water?
The concept here is osmosis. Bear in mind sea water is concentrated salt water. Then read the article at the link and see if you can answer the question.
http://en.wikipedia.org/wiki/Osmosis
I understand you're looking for help with understanding the concept of osmosis and its effects on organisms placed in different types of water.
To answer your first question: If a frog is placed in seawater (which is concentrated saltwater), it would experience a higher concentration of salt outside its body compared to the concentration of water inside its body. As a result, water would tend to move out of the frog's body through osmosis, from an area of lower solute concentration (inside the frog) to an area of higher solute concentration (the seawater). This can cause dehydration and potentially harm or even kill the frog.
For your second question: If a sea cucumber, which is typically found in seawater, is placed in fresh water (lower salt concentration), the opposite scenario occurs. The sea cucumber would have a higher concentration of salt inside its body compared to the lower concentration in the fresh water. Water would then tend to move into the sea cucumber's body through osmosis, seeking to equalize the concentrations inside and outside the sea cucumber. This influx of water can potentially lead to the rupture of the sea cucumber's cells, causing damage or death.
If you want to further explore the concept of osmosis, you can read the article on the topic on Wikipedia. It explains the process in more detail and provides examples of osmosis in different biological contexts.