People with HIV are unable to fight off these rare diseases because they have a weakened immune system.
Meristematic tissue have the ability to
divide themselves. It is the primary site for cell division and cell
differentiation. It produces the new cells and are called growing tissue in
plants. The new cells may or may not divide. It is the source of the regenerative
potential of the plant.
<span>
Cancerous cells can originate anywhere in the
body and can spread into or invade adjoining tissues. It keeps growing and dividing
relentlessly to form lumps. It can also break off and travel to distant
tissues. Cancer cells rejects signals from other cells.</span>
