This is an electron microscopic view of a plant stomate.

Stomata are the microscopic pores created by a pair of guard cells on plant surfaces, especially the leaves, which open and close to regulate gas and water exchange in all plants.

Click to view an open stomate.

Interest in how water moves through plants continues unabated after more than a century of study. Several hundred scientific papers are published each year which deal with the subject of stomata action, because this topic is critical to photosynthesis and crop production.