| A | B |
|---|
| primary xylem | from procambium (from apical meristem |
| secondary xylem | from vascular cambium (from lateral meristem) – can form wood |
| carnivorous leaves | designed to capture animals (mainly insects) to provide a nutrient supplement (common in swampy areas with sandy soil and high amounts of sunlight, where nitrogen and/or phosphorous may be limiting – example: southeastern U.S.) |
| shade leaves | leaves in shady areas have larger surface area and are thinner compared to leaves that receive more direct light |
| window leaves | cone-shaped leaves with a transparent tip; allows light into hollow interior, thus allowing some buried plant parts to have photosynthesis below ground |
| reproductive leaves | as in maternity plant, walking fern |
| spines | cacti and others – reduction in leaves reduces water loss and protects from predators |
| bracts | (floral leaves) – large, colorful leaves functionally act as petals; flowers usually inconspicuous (poinsettias, dogwoods) |
| leaf abscission | all plants lose leaves |
| abscission zone | at base of petiole |
| spongy mesophyll | loosely packed chlorenchyma nearer lower epidermis |
| palisade mesophyll | chlorenchyma in tightly packed rows close to the upper epidermis |
| mesophyll | between upper and lower epidermis |
| epidermis | transparent, most cells with no chloroplasts |
| rosette | a whorl at essentially ground level |
| alternate | single leaves occur on alternating sides, usually in a spiral |
| opposite | leaves occur in pairs on opposite sides of stem |
| axillary bud | at base of leaf |
| simple leaves | undivided (may have teeth or indentations |
| compound leaves | each blade divided into leaflets, leaflets don’t have axillary buds (compound leaf has one bud at base) |
| pinnately compound | leaflets in pairs along common axis |
| palmately compound | leaflets radiate from common point on petiole (examples – marijuana) |
