Sand is more Permeable. It is the smallest, and can diffuse the easiest over a membrane.
Salt water fish actually drink the salt water, excrete the salt, and are left with unsalted water in their body; they do this because the sea water, through the process of osmosis, draws out water from the body. <span>
When they are placed in fresh water, they continue to drink the water, but since the water is now less saline that the fish, water is no longer being drawn out, and in most cases (especially if the transfer was too quick), will start absorbing water, hence they will typically die. </span>
Protein
An enzyme is a catalytic protein that speeds up chemical reactions in the human body.
No, it is not a reasonable gamble for Karen to skip the influenza vaccine this year.
There are many factors which can increase a person's risk of developing the influenza virus and some of these factors are age, health condition, weakened immune system, pregnancy, or chronic illnesses.
Karen is older and her age could act as a risk factor for influenza. In addition, each year there are different strains of the virus since the virus is constantly changing and evolving. Given this, a person who got the vaccine last year is still in danger of not having the antibodies which can protect from this year's strain.
Karen should get the influenza vaccine this year as well.
older
the deeper you dig into the earth, the farther back into history you are going.