The answer to this question would be: enzyme
<span>Enzyme is a kind of catalyst that </span>will take part in the chemical reaction but it won't be reacted. E<span>nzyme </span>only helps by reducing the energy needed to start the reaction.
Theoretically, the enzyme is not mandatory needed but if you have an enzyme the reaction will be easier, thus increasing reaction speed. But in most case, the reaction might be too slow without enzyme, making enzyme vital in living organism.
The average mass of an atom is calculated with the formula:
average mass = abundance of isotope (1) × mass of isotope (1) + abundance of isotope (2) × mass of isotope (2) + ... an so on
For the boron we have two isotopes, so the formula will become:
average mass of boron = abundance of isotope (1) × mass of isotope (1) + abundance of isotope (2) × mass of isotope (2)
We plug in the values:
10.81 = 0.1980 × 10.012938 + 0.8020 × mass of isotope (2)
10.81 = 1.98 + 0.8020 × mass of isotope (2)
10.81 - 1.98 = 0.8020 × mass of isotope (2)
8.83 = 0.8020 × mass of isotope (2)
mass of isotope (2) = 8.83 / 0.8020
mass of isotope (2) = 11.009975
mass of isotope (1) = 10.012938 (given by the question)
Polar<span> covalent </span>bonding<span> is a type of </span>chemical bond <span>where a pair of electrons is unequally shared between two atoms.</span>
Sodium potassium pump is an active pump which transfer sodium and potassium ions across the membrane with the expenditure of energy in the form of ATP.
This kind of pump is generally used in nerve cells.
The pump works against the concentration gradient as the pump moves three Na+ ions outside the cell and two K+ ions inside the cell, though there is a high concentration of Na+ outside the cell and a low concentration of K+ outside the cell.