Relate the structure of xylem vessels to their function, limited to: (a) thick walls with lignin (details of lignification are not required) (b) no cell contents (c) cells joined end-to-end with no cross walls to form a long continuous tube

Identify and label the cuticle, cellular and tissue structures of a dicotyledonous leaf, as seen in diagrams or photomicrographs, and explain how these structures are adaptations for photosynthesis and gas exchange, limited to: (a) stomata and guard cells (b) spongy and palisade mesophyll cells (c) air spaces (d) vascular bundles (xylem and phloem) (e) distribution of chloroplasts (f) upper and lower epidermis