BY 124 1th Edition Lecture 2Outline of Last Lecture I. Characteristics of land plantsII. Derived Traits of Land Plants III. Plant EvolutionOutline of Current Lecture Chapter 29I. Nonvascular vs. Vascular Characteristics II. Nonvascular PlantsA. Life CycleB. PeatIII. Seedless Vascular PlantsA. LycophytaB. PterophytaChapter 30I. Three Advantages to seed plants over non-seeded/early plantsII. Review Figure 30.2III. Gymnosperms a. Gingkob. ConiferophytaCurrent LectureChapter 29 (cont.)I. Nonvascular vs. Vascular Characteristicsa. Nonvascular i. “bryophytes”- gametophyte (n) dominant1. Probably a good idea of what first land plants looked like2. Bryophytes ≠ Bryophyta a. Bryophytes is a collective term while Bryophyta is specific to just mossesii. No true roots, leaves or stems1. Rhizoid- root-like structureThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.a. Imbibe (absorb or soak up) using concentration gradient2. Can have leaf-like structures but not the same thing as leavesiii. No ligniniv. Not adapted to land wellv. Have a cuticlevi. Retain embryo in female part of plantb. Vasculari. “tracheophytes”- sporophyte dominant (2n)1. Named so because they have tracheids (type off xylem cell)ii. Xylem and phloem1. Xylema. Dead at maturityb. Used for support (cell wall)c. Transports water throughout celli. can only move up2. Phloema. Transports sugari. Can move both up and down plantiii. True roots, leaves, and stemsII. Nonvascular Plants a. Life Cycle of Moss (Figure 29.8)i. Female (F) and Male (M) gametophyte1. Dominant form= gametophyte (2n) → mitosis to make egg and sperma. Sperm needs water to find egg2. Egg retained in F part of plant3. Sporophyte grows out of gametophyte → meiosis to create spores(n) from sporangiumi. Spores never released all at one time so as to account for possible unfavorable conditionsb. Capsules holding spores use seta (stem-like) structures to stay upi. Can reproduce asexually using gimmaeb. Peat (Figure 29.11)i. Used for fuel and scotch – Scotland ii. Bog mummiesIII. Seedless Vascular Plants a. Phylum Lycophyta (Figure 29.15)i. Sporophylls are modified stems that create sporangia 1. Sori (found in Pterophyta)- clusters of sporangia (dots on backs of leaves)2. Strobili- clusters of sporophylls (cone-like)ii. Homosporous spore production (seedless plants)1. Sporangium on sporophyll → single type of spore → typically bisexual gametophyte → egg or spermiii. Heterosporous spore production (ALL seed plants)1. Megasporangium → megaspore → F gametophyte → egg2. Microsporangium → microspore → M gametophyte → spermiv. Club moss is NOT nonvascular (therefore sporophyte dominant)v. Flagellated spermvi. True rootsvii. Rhizomes- horizontal stemsviii. Gametophyte is separate and lives underground1. Symbiotic relationship with fungus that feeds itb. Phylum Pterophyta (Figure 29.15)i. Arose during Devonian and Carboniferous Period1. Many died out during Carboniferous Period formed coalii. Horsetails1. Abrasive due to silica in cell wall2. Underground rhizomes3. Has photosynthetic abilityiii. Ferns are vascular plants that DO NOT make seeds a. Early “trees”b. Flagellated sperm2. Life cycle (Figure 29.13)a. Homosporous- prothallusb. Gametophyte (bisexual) grows out of sporec. Sexual reproduction is possible! But F and M parts develop at different times so that self-pollination is unlikelyi. Can be asexual because of meristem capabilityChapter 30: Plant Diversity II: The Evolution of Seed Plants a. Seed plants –dominant plants of todayi. Arose because the end of the Carboniferous period was dryI. Three Advantages to seed plants over non-seeded/early plantsa. Pollen grain replaces swimming spermb. Gametophyte is reduced and maintained in sporophytei. Not photosynthetic or free-livingc. Heterospores – seed encloses embryo for protection and food i. Seed distributes species instead of sporeII. Review Figure 30.2III. Gymnosperms (Figure 30.3 and Figure 30.5)i. Gymnospore – “naked seed”1. Not enclosed in an ovarya. Gingko – only Gingko in phylum b. Conifers (Coniferophyta)ii. Examples: . Juniper, pine, sequoias, Douglas fir1. Pine trees = Heterosporous (two different sex structures)a. Outside of seed comes from momb. Megaspore give gametophyte generationc. Embryo develops and nourished by gametophytei. All retained within seediii. Life cycle of a Pine tree (Figure 30.6)1.a. Mature pollen grain holds tube cells, sperm cells, and sterile cells2. Microsporangium (2n) → meiosis → pollen grain (n)3. Ovulate cone (2n)a. Megasporangium → meiosis → haploid megaspores4. Pollen blown by wind5. Some plants have an immunological defense against self-pollination to allow for more diversity6. “stickiness” of pine cone draws in pollen to fertilize 7. Archegonium is similar to ovary off humana. Where fertilization occursi. Fertilization can occur 15 months after pollination8. Cone protects female gametophyteMature pollen grain (n)Generative cell Sperm cellSterile cellTube