My husband and I *love* to walk ...for hours and hours, and if we decide to go ahead with this potential trip - I'm going to need good shoes. These days, I have some reasonably good shoes for the most part - but they are 2-3 hour walking shoes, not necessarily good for 6+ hours of tromping around.
In cell biology, selective permeability is the property of a living cell membrane that allows the cell to control which molecules can pass through the membrane, moving into or out of the cell.
A community for students. When we say the cell membrane is selectively permeable, we mean that A. the cell is bathed in liquid. B. oxygen and water cannot enter the cell. C. some substances can pass through the membrane. D. it has a high concentration of salt. By this we actually mean that only some substances can pass through the membrane.