2. Inside stems I. Herbaceous stems A. Epidermis B. Cortex and pith C. Vascular bundles: primary xylem and phloem II. Stem thickening: wood A. Development of vascular cambium B. Cork cambium C. Other features of wood 1. sapwood and heartwood 2. vascular rays 3. growth rings III. Monocot stems

3. I. Herbaceous stems A. Epidermis B. Cortex and pith C. Vascular bundles: primary xylem and phloem cuticle cortex

4. II. Stem thickening: wood A. Development of vascular cambium B. Cork cambium

5. C. Other features of wood 1. sapwood and heartwood 2. vascular rays 3. growth rings

6. Conifer wood and dicot wood Tracheids Vessel elements

7. III. Monocot stems

8. The end