Each shell can contain only a fixed number of electrons: The first shell can hold up to two electrons, the second shell can hold up to eight (2 + 6) electrons, the third shell can hold up to 18 (2 + 6 + 10) and so on. The general formula is that the nth shell can in principle hold up to 2(n2) electrons.
There all have feathers and lay eggs.
Cell specialization allows cells to perform essential cell specific tasks. Such as nerve cells, red blood cells etc.
The answer to the question presented above would be 'require frequent rainfall'. A plant native to the chaparral would be expected to require frequent rainfall. This is because it cannot survive in dry lands and without constant water.
