Plants

Respiratory System

Stomata

Description

Plants need to breathe, too! Just like our cells, the cells in a plant are working hard, and need energy. Plants need oxygen to get the energy out of the food they make. Obviously, plants don't have lungs or gills, so how do they breathe? They breathe through special little holes on the underside of their leaves called stomata.

The stomata allow fresh air to enter the leaf, where the plant's cells can take out the oxygen. When the oxygen is used up, the air can flow back outside through the stomata again.

Neat Stuff

Plants have special cells surrounding the stomata called guard cells. The guard cells can squeeze over the opening, to close up the hole. This is useful when it's very dry out, and the plant doesn't want to lose any water through the stomata. It's also useful as a defense against small insects, which can sometimes crawl through the opening and into the leaf.