A selectively permeable membrane allows some small substances to pass through but prevents larger substances doing the same. The cell wall is totally permeable and has no role in controlling what ...

Most of the water that enters a plant will exit the leaf into the atmosphere. This provides a continuous stream of water which is known as the transpiration stream. Surface area (not an environmental ...

In a confined space, bacteria can change their environment in their favour. In an open and mixed environment, by contrast, bacteria must cooperate to carry out these functions, such as the production ...

Old paper banknotes potentially worth hundreds of pounds could be lurking in your wallet. Paper £5, £10, £20 and £50 notes are no longer legal tender after being withdrawn and replaced with polymer ...

Treasury bonds, notes and bills are U.S. government debt securities that mainly differ in their duration, the interest they pay and the amount of interest rate risk they face. Many, or all, of the ...