Leaf Parts

Waxy Cuticle

A lipid layer used to water poof the leaf and ensure the plant does not lose water through evaporation. The wax is secreted by the upper epidermis.

Upper Epidermis

The top layer of the leaf, known as the dorsal side of the leaf.

Palisade Layer

Part of the mesophyll layer of the leaf, where photosynthesis occurs. In the palisade layer, the plant cells are elongated and tightly packed together, which allows for ample space between the cells.

Spongy Mesophyll

Part of the mesophyll layer of the leaf, where photosynthesis occurs. In the spongy mesophyll, the cells are rounded and loosely packed together, which allows for ample space between the cells.

Lower Epidermis

The bottom layer of the leaf, known as the ventral (belly) side

Air Spaces

These spaces cause the spongy mesopyll to have a spongy texture. They fill with gases used in photosynthesis and allow the gasses to move around freely and diffuse into cells.G

Guard Cells

Regulate the stomate by opening and closing. When there is an abundance of water, the guard cells fill with water and bend outward. When there is a lack of water, the turgor pressure in the guard cells decrease and the stomate is closed. The opening and closing regulates water loss.

Vein

Supplies the leaf with water and nutrients and is made of xylem and phloem. Xylem transports water and the pathway water takes to get to the photosynthetic cells is: roots → veins → cells in the mesophyll layer. Phloem transports glucose and when glucose is made in the mesophyll layers, the extra glucose is transported to other parts of the plant via the phloem in the vein. Extra glucose is served in the roots of the plant.

Bundle Sheath

A layer of cells that surround the vein and are used to store carbon dioxide. These are especially important in autotrophs of C4 plants.

Stomate

Openings found on the surface of the leaf that allow gases in and out of the leaf- CO2 enters and O2 exits. If left open for too long, the leaf can lose water in the form of water vapor.