Why are the stomata and guard cells of a plant important? and what does it do? thankds:D?

Question

Why are the stomata and guard cells of a plant important? and what does it do? thankds:D?

Answer 1

A "stoma" (plural stomata) is a tiny opening or pore, found mostly on the underside of a plant leaf and used for gas exchange. The pore is formed by a pair of specialized parenchyma cells known as guard cells which are responsible for regulating the size of the opening. Air containing carbon dioxide enters the plant through these openings where it is used in photosynthesis and respiration. Oxygen produced by photosynthesis in the spongy layer cells (parenchyma cells with pectin) of the leaf interior exits through these same openings. Also, water vapor is released into the atmosphere through these pores in a process called transpiration.

From: http://en.wikipedia.org/wiki/Stoma

Also see: http://www.tvdsb.on.ca/westmin/science/s...

Answer 2

Guard   cells  control the transpiration, an important process of the plant. They are present around the tiny pores called stomata  which are present on  upper and lower surface of the leaf.