Answer:
Molecules which move against the concentration gradient across the cell membrane employ the mechanism of active transportation.
Explanation:
Normally, permitted molecules moves across the cell membrane of the cell by the process of diffusion and osmosis. This is used when molecules move from hypertonic region to hypotonic region (if ions) and hypotonic to hypertonic (if water). This is a passive transportation which do not require the expense of energy from the cell.
In contrast, when molecules move in or out of the cell against their concentration gradient, that is ions moving from hypotonic region to hypertonic region, they implore the expense of energy in form of adenosine triphosphate (ATP), and the involvement of the membrane carrier proteins. This is called active transport.
The majority of Earth's atmosphere contain 78% is nitrogen, The Nitrogen cycle is the geochemical cycle in which nitrogen is converted into multiple chemical forms. Nitrogen cycle occurs in terrestrial and marine ecosystem. Nitrogen can be converted through both biological and physical process. The processes that are involved in nitrogen cycle are fixation, ammonification, nitrification, and denitrification.
There is limited amount of nitrogen that is useful but <u>increase of fossil fuel combustion, use of artificial nitrogen fertilizer</u> have dramatically increased the amount of nitrogen in nitrogen cycle.
The first three are the same as those found in DNA, but in RNA thymine is replaced by uracil as the base complementary to adenine. This base is also a pyrimidine and is very similar to thymine. Uracil is energetically less expensive to produce than thymine, which may account for its use in RNA.
Because water is so good at storing heat energy, it is harder for organisms to experience a change in body temperature in harsher climates.
It is found in the understory or the lower canopy
