Pine Leaf Cross Section

Much detail can be found in seemingly simple pine leaves, better known as pine needles. Though they have characteristic shapes, these leaves still have the fundamental elements which constitute a leaf. Their differences have evolved in response to their environment, making them more durable than normal leaves and better suited for cold climates. 

Objective: 4x (previous 2 photos)

The thin yellow perimeter marks the leaf's cuticle, and the cup-like openings are the stoma. The stoma allow gas exchange to occur in the leaf.

The pink ovals in the center are the xylem, while the blue ovals beside them are the phloem. The xylem transports water and minerals throughout the plant, while the phloem moves the nutrients that the leaf produces.

Objective: 10x

At this magnification, the nuclei in the individual cells are visible. 

Objective: 40x (previous 2 photos)

The large pink dots are the nuclei, while the many small green dots are the chloroplasts. These are the structures that enable photosynthesis itself to happen.