| A | B |
|---|
| aerial roots | may be photosynthetic (some epiphytes), prop roots (like corn) branch near soil for support, adventitious roots – leave plant other than at base |
| pneumatophores | rise above water in aquatic trees; can function for gas exchange (mangroves, probably bald cypress) |
| contractile roots | pull plant deeper (lilies) |
| parasitic roots | penetrate host, haustoria for feeding from host |
| food storage roots | extra parenchyma cells (sweet potatoes; part root/part stem for carrots, beets, radishes, parsnips, turnips) |
| water storage roots | in some members of pumpkin family in arid regions; some over 100 lbs. |
| buttress roots | extra support (some figs and tropical trees) |
| axis | where leaves attach in spirals, whorls of 3+, or opposite pairs |
| node | where leaf is attached |
| internode | area between nodes |
| axillary bud | between leaf and stem, may form new stem or flowers |
| terminal bud – | extend length of stem |
| apical meristems at tips | lengthens stem |
| parenchyma in center | pith |
| vascular cambium | divides to form secondary vascular tissues, increasing girth |
| cork cambium | in woody stems – |
| lenticels | some cells from cork cambium unsuberized, permit gas exchange |
| monocot stems | herbaceous, vascular bundles dispersed |
| herbaceous dicots | vascular bundles arranged in ring |
| secondary xylem | wood |
