Leaf Structure Mr. Hefti – Pulaski Biology
Identification: 1.Cuticle 2.Upper epidermis 3.Mesophyll Transport tissues Xylem Phloem Palisade layer Spongy layer Air spaces 4. Lower epidermis Guard cell Stoma ~ Leaf Cross Section ~
Cuticle Waxy outer coating that protects leaf
Upper epidermis Top layer of cells
Mesophyll Middle layer – packed with chloroplasts –Transport tissues / veins Xylem: transports water Phloem: transports food –Palisade layer: tightly packed columnar cells –Spongy layer: loosely packed with many air spaces Air spaces: openings for moving gases
Lower epidermis Guard cell: opens and closes stoma Stoma: pores in leaves that connect to air spaces
Now take a look at some lilac leaf specimens!