<span>The cells that are on each side of the stomatal pore and open and close
it like a mouth is called <u>guard cells</u>. Guard cells are found almost all
over the body part of the plant. The opening and closing of the stomata acts as
a mediator by changes in turgor pressure of the guard cells. Turgor pressure
pushes and sometimes out of the cell wall of the plant to allow ions of
solution to come in and out. The stomatal pore of the guard cell becomes large
when water is present around it and it is small when water is not present. </span>
Question is not properly asked or mentioned .
Explanation: Elephants have been extensively hunted for ivory for more than 300 years, natural selection is often proposed as the underlying mechanism for an increase in the proportion of tuskless or small-tusked elephants in a population.
Active Transport<span> is used when substances are to be transported against their concentration gradient ( from low concentration to high concentration ) by utilising energy from ATP.
</span>
eg - Na+/K+ pump.
hope it helps u.....
Vucueil and Plast (including chloroplasts) and cell wall.