1. Greek: By far the most diverse group of plants that has ever existed with more than 240,000 different species. The angiosperms angeion case; sperma seed

2. Time of origin of plant groups

3. Why are there do many species? Mosses Ferns Angiosperms Why are there so many species? Conifers

4. Gondwanaland West Gondwana, equivalent to modern South America plus Africa

5. Two things before discussing the Angiosperms: [A] Simple tissues of parenchyma, collenchyma and sclerenchyma [B] There are two classes of flowering plants, Monocotyledons and Dicotyledons

6. Fig. 29.5, p. 502 [A] Simple tissues of parenchyma, collenchyma and sclerenchyma Transverse section pholem sclerenchyma collenchyma parenchyma Important structural tissues of many angiosperms xylem epidermis

7. Examples Fig. 29.6, p. 502 PARENCHYMA COLLENCHYMA SCLERENCHYMA

8. DICOTS Dicotyledon – Monocotyledon differences MONOCOTS Fig. 29.10, p. 503 In seeds, two cotyledons (part of the embryo ) Usually four or five floral parts (or multiples of these) Usually a netlike array of leaf veins Basically, three pores of furrows in pollen grain In seeds only one cotyledon Usually three floral parts (or multiples of three) Usually a parallel array of leaf veins Basically, one pore or furrow in pollen grain Vascular bundles distributed ground tissue of stem Vascular bundles arrayed as a ring in stem vascular bundle [B] There are two classes of flowering plants, Monocotyledons and Dicotyledons

9. 1. Angiosperm leaves have finely divided venation; typically gymnosperm foliage e.g., conifer needles, have a single vascular strand 6. In the angiosperms there are generally hermaphrodite flowers and cross pollinating (70%). Wind pollination is typical in the gymnosperms animal pollination widespread in angiosperms 4. Angiosperm ovules are protected within an enclosed structure rather sitting on a modified leaf 5. Double fertilization in the angiosperms produces a diploid zygote and triploid endosperm nucleus 2. Angiosperm xylem contains vessels as well as tracheids and parenchyma 3. Angiosperm phloem contains sieve elements with companion cells rather than albuminous cells Principal differences between Angiosperms and Gymnosperms

10. The network of veins also provides a supportive framework for the leaf. 1. Leaves have finely divided venation Coleus leaf cleared of cell contents and with xylem stained A dicotyledon Typically veins are distributed such that mesophyll cells are close to a vein. So? Why is that important?

11. Leaf of a monocotyledon plant The major venation follows the long axis of the leaf and there are numerous joining cross veins so that, as with the dicotyledon, mesophyll cells are always close to a vein.

12. Diagram of a dicot leaf Fig. 29.16, p. 507 Water and dissolved mineral ions move from roots into stems, then into leaf vein (blue arrow) Products of Photosynthesis (pink arrow) enter vein and are transported to stems, roots) one stoma (opening across the epidermis) cuticle-coated cell of lower epidermis PALISADE MESOPHYLL SPONGY MESOPHYLL Carbon dioxide from the surrounding air enters the leaf through stomata Oxygen and water vapor escape from the leaf through stomata xylemphloem leaf vein (one vascular bundle inside the leaf) UPPER EPIDERMIS LOWER EPIDERMIS cuticle of upper epidermis My textbook has xylem and phloem wrongly labeled

13. Tomato leaf Upper epidermis Lower epidermis Palisade parenchyma: chloroplasts visible around cell periphery Spongy parenchyma Longitudinal section through a vascular bundle Xylem vessel: annular thickening around cell wall Phloem Bundle Sheath

14. … C3 and C4 photosynthesis? MonocotsDicots

15. http://www.uri.edu/artsci/bio/plant_anatomy/99.html Leaf cross section of Zea mays ("corn"). Bulliform cellsXylemUpper epidermis Lower epidermis Bundle sheath cells with chloroplasts Phloem Parenchyma with chloroplasts

16. Xylem Bundle sheath cells filled with chloroplasts. CALVIN REACTION SITE Phloem Parenchyma filled with chloroplasts C4 acids synthesized in the parenchyma move to the bundle sheath Carbon skeleton compounds return to parenchyma Anatomical separation of the C4 photosynthesis component processes Maize 3394

17. 2. Xylem contains vessels as well as tracheids and parenchyma Elongated vessel element: This cell provides moderate support but superior fluid conduction compared to a tracheid. Vessel A vessel is composed of several vessel elements Wide vessel element: This kind of cell is better for fluid conduction than physical support. These vessel elements have completely perforated end walls Tracheid Tracheids provide better support but less slower rates of water conduction than vessels Tracheids lack perforation plates but their end walls contain numerous pits.

18. 3. Phloem contains sieve elements with companion cells STMs have no nucleus at maturity and depend on CC to regulate physiological processes. Sieve Tube Members (STM) Sieve plate Cucurbita phloem Companion Cells (CC) (cucumber) STMs and CCs develop from the same progenitor cell. STMs unite vertically to form a Sieve Tube.

19. Stems as diverse as slender vines, fat cacti, or as modified as potato tubers all have this organization, but with various zones modified. Dicotyledon stem cross section Angelica stem transverse section Typical of a dicotyledon without secondary thickening. J. D. Mauseth We eat Angelica in confectionary 1) epidermis 2) cortex, in many species the outermost part is a hypodermis 3) ring of vascular bundles 4) pith. Four zones: Cacti have an exceptionally thick cortex. Potato tubers have a gigantic pith and almost no wood.

20. Transverse section of corn stem, Zea mays. Organization of monocotyledon stems: numerous vascular bundles distributed throughout a tissue that may be either parenchyma or collenchyma There are four parts: 3) vascular bundles 2) cortex with or without part differentiated into a hypodermis 1) epidermis 4) a matrix of parenchyma called conjunctive tissue or pith Monocotyledon stems: numerous vascular bundles distributed throughout a tissue that may be either parenchyma or collenchyma