BY 124 1th Edition Lecture 2 Outline of Last Lecture I Characteristics of land plants II III Derived Traits of Land Plants Plant Evolution Outline of Current Lecture Chapter 29 I Nonvascular vs Vascular Characteristics II Nonvascular Plants A Life Cycle B Peat III Seedless Vascular Plants A Lycophyta B Pterophyta Chapter 30 I II III Three Advantages to seed plants over non seeded early plants Review Figure 30 2 Gymnosperms a Gingko b Coniferophyta Current Lecture Chapter 29 cont I Nonvascular vs Vascular Characteristics a Nonvascular i bryophytes gametophyte n dominant 1 Probably a good idea of what first land plants looked like 2 Bryophytes Bryophyta a Bryophytes is a collective term while Bryophyta is specific to just mosses ii No true roots leaves or stems 1 Rhizoid root like structure These 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 II III a Imbibe absorb or soak up using concentration gradient 2 Can have leaf like structures but not the same thing as leaves iii No lignin iv Not adapted to land well v Have a cuticle vi Retain embryo in female part of plant b Vascular i tracheophytes sporophyte dominant 2n 1 Named so because they have tracheids type off xylem cell ii Xylem and phloem 1 Xylem a Dead at maturity b Used for support cell wall c Transports water throughout cell i can only move up 2 Phloem a Transports sugar i Can move both up and down plant iii True roots leaves and stems Nonvascular Plants a Life Cycle of Moss Figure 29 8 i Female F and Male M gametophyte 1 Dominant form gametophyte 2n mitosis to make egg and sperm a Sperm needs water to find egg 2 Egg retained in F part of plant 3 Sporophyte grows out of gametophyte meiosis to create spores n from sporangium i Spores never released all at one time so as to account for possible unfavorable conditions b Capsules holding spores use seta stem like structures to stay up i Can reproduce asexually using gimmae b Peat Figure 29 11 i Used for fuel and scotch Scotland ii Bog mummies 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 sperm iii Heterosporous spore production ALL seed plants 1 Megasporangium megaspore F gametophyte egg 2 Microsporangium microspore M gametophyte sperm iv Club moss is NOT nonvascular therefore sporophyte dominant v Flagellated sperm vi True roots vii Rhizomes horizontal stems viii Gametophyte is separate and lives underground 1 Symbiotic relationship with fungus that feeds it b Phylum Pterophyta Figure 29 15 i Arose during Devonian and Carboniferous Period 1 Many died out during Carboniferous Period formed coal ii Horsetails 1 Abrasive due to silica in cell wall 2 Underground rhizomes 3 Has photosynthetic ability iii Ferns are vascular plants that DO NOT make seeds a Early trees b Flagellated sperm 2 Life cycle Figure 29 13 a Homosporous prothallus b Gametophyte bisexual grows out of spore c Sexual reproduction is possible But F and M parts develop at different times so that self pollination is unlikely i Can be asexual because of meristem capability Chapter 30 Plant Diversity II The Evolution of Seed Plants I II III a Seed plants dominant plants of today i Arose because the end of the Carboniferous period was dry Three Advantages to seed plants over non seeded early plants a Pollen grain replaces swimming sperm b Gametophyte is reduced and maintained in sporophyte i Not photosynthetic or free living c Heterospores seed encloses embryo for protection and food i Seed distributes species instead of spore Review Figure 30 2 Gymnosperms Figure 30 3 and Figure 30 5 i Gymnospore naked seed 1 Not enclosed in an ovary a Gingko only Gingko in phylum b Conifers Coniferophyta ii Examples Juniper pine sequoias Douglas fir 1 Pine trees Heterosporous two different sex structures a Outside of seed comes from mom b Megaspore give gametophyte generation c Embryo develops and nourished by gametophyte i All retained within seed iii Life cycle of a Pine tree Figure 30 6 1 T M G S a e p t u t n e b u r e i r m e a l c t c e p i e l o v c l l e l e c l e n l g l r a i n n 2 3 4 5 6 7 8 a Mature pollen grain holds tube cells sperm cells and sterile cells Microsporangium 2n meiosis pollen grain n Ovulate cone 2n a Megasporangium meiosis haploid megaspores Pollen blown by wind Some plants have an immunological defense against selfpollination to allow for more diversity stickiness of pine cone draws in pollen to fertilize Archegonium is similar to ovary off human a Where fertilization occurs i Fertilization can occur 15 months after pollination Cone protects female gametophyte