the answer is the trophic level
A typical human karyotype has 23 types of chromosomes arranged from largest to smallest. In males and females 22 of these chromosomes look exactly the same and they are called autosomes. The 23rd pair of chromosomes is the sex chromosome which differentiates males from females. Females have 2 copies of the x chromosome. Males have a copy of both x and y chromosome to make the 23rd pair. <span>
<span>Chromosomes can also have abnormalities that result to different conditions and identifiable traits. A most common chromosomal abnormality is the condition called Down Syndrome, where chromosome 21 has a third copy because of an abnormal cell division.</span></span>
They adapt because they can replicate quickly (have many generations within short period of time) and accumulate mutations. Mutations in their genetic information allows them to bypass the host's immune system or resist to antibiotics. These mutations are successfully carried to the next generations of bacteria and allows them to thrive in their new environments. <span />
