LEAF ANATOMY

This diagram contains the vital and basic parts of a leaf in a cross section. These are necessary for the leaf to perform its function:

Cuticle: Acts as a permeablilty barrier for water, and prevents the contamination of plant tissues with outer materials, such as dirt or microbes.

Upper Epidermis: A single layer of cells that permits most of the light to pass through, and is covered with the waterproof cuticle.

Palisade mesophyll cell: These cells are filed with chloroplasts, usually very many. The contents in these cells are responsible for photosynthesis

Bundle sheath cell: They impart strength to the vein, giving it a stiff fram to support soft tissues of the leaf blade.

Xylem: Supplies water and minerals to other cells. Sends nutrients up

Phloem: Needed to remove synthesized food.  Sends nutrients down

Lower Epidermis: Holds most of the stoma/stomata, which are flanked by guard cells.

Sponge mesophyll cells: They are the temporary storage structures of sugars and amino acids made in the palisade cells.  Spongy mesophyll cells are more spread out than palisade mesophyll cells because there are intercellular air spaces.  They contain fewer chloroplasts than the palisade layer.

Guard cell: Found in the lower epidermis by the stoma, and control the opening and closing of them, in turn controlling the exhange of gases between the lead and the atmosphere.

Stoma: Pores in lower epidermis where gases are exchanged between a leaf and its surroundings. They are essentially respiration sites for the leaf, where CO2 is taken in, and O2 is released.

Vein: They are close to the palisade and spongy mesophyll cells to supply them with nutrients like water and minerals, as well as whisk away synthesized food and glucose. Holds the Xylem and Phloem