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1 Lab Review for Plant Diversity Pieces of this lesson may be incorporated into your own lessons for delivery in lab or discussion. It is associated with a slide show which may ne accessed at I. Plants have an alternation of generations (images 1a through 1f): All plants have an alternation of generations. Gametes are produced by a haploid plant termed the gametophyte through mitosis. Spores are produced by a diploid plant termed a sporophyte through meiosis. Plants together with the Charophycean green algae form a clade. The Charophycean green algae do not have an alternation of generations, but have zygotic meiosis. The sporophytic generation in plants can be thought of as an adaptation for life on land. By generating multiple diploid cells through mitosis after fertilization, more spores are generated for each fertilization event (a more improbable event on land). At the start of plant evolution, the gametophyte was certainly the preeminent vegetative stage associated with dependent spore-generating sporophytes. The life cycle of Riccia most closely matches this hypothesis. This condition was flipped by the differing selective pressures of the reproductive cycle between the sporophyte and gametophyte. Plants are oogamous and require films of water for swimming sperm. As relative humidity decreases with elevation, it is maladaptive for gametophytes to become large. However, it is adaptive for sporophytes to become large as height is adaptive in that its spores are more effectively dispersed.1a = Fern life cycle 1b = Chara: one generation 1ba = habit of Riccia gametophyte 1bb = Riccia archegonium 1bc = Riccia antheridium 1bd = Riccia young sporophyte 1ba = Riccia Mature sporophyte with meiospores 1c = Moss view of 2 generations 1d = Psilotum life cycle 1e = Conifer Life Cycle 1f = Angiosperm life cycle II. Know these clades Liverworts - (starts at 2a) simple plants without vascular tissue or stomata. Gametophytes are independent, the sporophytes are dependent all their lives on the gametophyte. You should recognize Marchantia, air pores of the thallus, archegoniophores, archegonia (with neck, venter and egg), antheridiophores, and antheridia, sporophytes with sporangium containing spores: 2a =Thallus of Marchantia 2b =XS of Thallus: air pore of Marchantia 2c =Structures of life cycle of Marchantia

2 Hornworts - (starts at 2c) simple plants without vascular tissue. Chloroplasts have pyrenoids and sporophytes have stomata. Gametophytes are independent, the sporophytes are dependent all their lives on the gametophyte: 2d. Hornwort, 2 generations 2e. Hornwort, Algal-like chloroplasts of gametophyte 2f. Hornwort, stoma of sporophyte Mosses - (starts at 2f) more complex with stomata, and conductive tissues homologous to xylem and phloem, but still considered to be a non-vascular plant. Gametophytes are independent, the sporophytes are dependent all their lives on the gametophyte. You should recognize gametophytes vs sporophyte, archegonia (with venter, neck and egg), antheridia, and sporophyte with sporangium, and protonemeta as the first stage of growth of the gametophyte: 2g. Mosses, view of two generations 2h. Mosses, view of two generations 2i. Mosses, protonemata Lycophytes- (starts at 2j) A group of vascular plants. Both the gametophyte and sporophyte are independent, but the gametophyte is reduced. Only the sporophyte has vascular tissues. The leaves are microphylls and are not homologous to the leaves of other plants. These leaves do not have leaf gaps or axillary buds. Branching occurs by the splitting of the apical meristem giving rise to a dichotomous fork. You should recognize homosporous examples as club mosses and the heterosporous genus, Selaginella.: 2j. Club moss sporophytes 2k. Club moss microphyll xs 2l. Selaginella with strobili - habit 2m. Selaginella strobili l.s Ferns and their Relatives Ferns - (starts at 2n) A group of vascular plants. Both the gametophyte and sporophyte are independent, but the gametophyte is reduced. Only the sporophyte has vascular tissues. You should recognize a sporophyte, and the parts of a sporophyte (rhizome, frond=leaf, sori), and the tissues of the rhizome, and the sporangia and spores. You should recognize a gametophyte with its archegonia (with neck, venter and egg) and antheridia. 2n. Fern life cycle 2o. Fern sporophyte - morphology 2p. Fern sporophyte - xs rhizome 2q. Fern sporophyte - sorus l.s. 2r. Fern l.s. sporangium Wisk Ferns - (starts at 2s) A group of structurally simple ferns. Both the gametophyte and sporophyte are independent, but the gametophyte is reduced. Only the sporophyte has vascular tissues. The sporophyte lacks leaves and roots, branching occurs through the dichotomous splitting of the apical meristem of the stem. You should recognize Psilotum, and the sporangium of Psilotum.

3 2s. Habit of Psilotum 2t. Sporangium of Psilotum Horsetails - (starts at 2u) A group of structurally complex ferns. Both the gametophyte and sporophyte are independent, but the gametophyte is reduced. Only the sporophyte has vascular tissues. The sporophyte has both leaves and roots. The leaves are whorled and are non-photosynthetic. There are buds associated with the nodes that can give rise to whorls of branches. You should recognize Equisetum: 2u. Habit of Equisetum 2v. Whorled branches of of Equisetum 2w. Wholed fused leaves of Equisetum Conifers - (starts at 3a) Seed plants. As with all seed plants these are tissue in the seed is the megagametophyte. Conifers have compound ovulate cones consisting of seed scale complexes. You should recognize Pinus. 3a. Pine life cycle 3b. Pine ovule 3c. Pine ovulate cone 3d. Red Pine - habit Cycads - (starts at 3e) Seed plants. As with all seed plants these are tissue in the seed is the megagametophyte. Cycads have megasporophylls as well as microsporophylls which may be arranged into terminal clusters forming cones (strobili). Cycads have pinnately compound leaves and look palm-like. 3e. Cycas - habit 3f. Cycas - megasporophylls 3g. Cycas - microsporophylls Ginkgoes (starts at 3h) Seed plants. As with all seed plants these are tissue in the seed is the megagametophyte. There is only one surviving species, Ginkgo biloba which you should recognize. 3h. Ginkgo - habit 3i. Ginkgo - ovules and leaf 3j. Ginkgo - ripe ovules

4 Gnetophytes - (starts at 3k) Seed plants. As with all seed plants these are tissue in the seed is the megagametophyte. This consists of three different genera which are radically different in appearance. If you see two of these genera you should be able to recognize these to this group. 3k. Gnetum - habit with ovules 3l. Ephedra - habit 3m. Welwitschia male female plants Flowering Plants (starts at 3n) Seed plants. As with all seed plants these are tissue in the seed is not a megagametophyte. Angiosperms are unique in that their ovules are enclosed in a megasporophyll, the carpel, and by double fertilization. Pollination results in the union of one sperm nucleus with the egg to produce the zygote; and in the union of another sperm with two polar nuclei giving rise to a primary endosperm nucleus. The primary endosperm nucleus develops into endosperm. Double fertilization destroys the megagametophye. Nutritive tissue in the mature seed consists either of endosperm, or else of cotyledons which are the seed leaves of the embryo. In angiosperms the carpel matures into a fruit. 3n. Angiosperm life cycle 3o. Lily Flowers 3p. Pollen grain 3q. Embryo sac 3r. Ovary xs 3s. Ovules 3t. Double fertilization 3u. Fruit III. Understand/recognize these concepts/structures (Starts at 4a) Archegonium (4a - 4c) Archegoniophore (4ea) 3. Antheridium (4f-4h) 4. Antheridiophore (4i) 5. Aggregate fruit (4j) 6. Androecium (4k) 7. Anther (4l) 8. Berry (4m) 9. Calyx (4n) 10. Capsule (4o) 11. Carpel (4p) 12. Cone = strobilus (4r - 4ra) 13. Corolla (4rz) 14. Dioecious (4sa-4t) 15. Double Fertilization (4u) 16. Egg (4v-4x) 17. Embryo (4z-5a) 18. Embryo Sac (5az) 19. Endosperm (5ba) 20. fertilization=syngamy (5bb) 21. Follicle (5c) 22. Fruit (5d)

5 23. Flower Complete (5e) Incomplete but perfect (5f) Imperfect (5g) Monoecious (5h-5ha) Dioecious (5i) 24. Gametophyte (5j) 25. Grain (5k) 26. Gynoecium (5l) 27. Heterospory (5m) 28. Inferior (5n) 29. Integument (5o) 30. Locule (5p) 31. Megaspore (5q) 32. Megaspore Mother Cell (5r) 33. Megasporangium (5s) 34. Megasporophyll (5t) 35. Megagametophyte (5u) 36. Microspore (5v) 37. Microsporangium (5w) 38. Microsporophyll (5x) 37. Microgametophyte (5y) 38. Microspore Mother Cell (5z) 39. Monoecious (6a) 40. Multiple Fruit (6b) 41. Nucellus=megasporangium of a seed plant (see megasporangium) (6bz) 42. Nut (6c) 43. Ovary (6d) 44. Ovule (6da) 45. Petals (6e) 46. Pistil (6f) 47. Pollen Grain (6g) 48. Pollen Tube (6h) 49 Pollination (6i) 50. Primary Endosperm Nucleus (6j) 51. Pyrenoid (6k) 52. Samara (6l) 53. Seed (6m) 54. Sepal (6o) 55. Pome (6p) 56. Receptacle (6pz) 57. Stoma (6q) 58. Stigma (6r) 59. Style (6r) 59. Tapetum (6s) 60. Tube Cell (6t)