3 Evolution from Bryophytes to Seedless Vascular Plants Development of Vascular TissueXylem – conducts water and dissolved mineralsPhloem – conducts dissolved sugarVascular tissue allows for taller plantsDominant sporophyte generationReproduction still depends on water to transport spermEvolution of True Leaves
4 Evolution of True Leaves 2 Types of True LeavesMicrophyllsType of leaf found in lycophytesContains one vascular strandMegaphyllsType of leaf found in ferns, horsetails, and seed plantsContains multiple vascular strands (branched)Probably evolved from the webbing of side branches
6 Ferns Phylum Pteridophyta Remember: “I’m Terrified of Ferns” Seedless - Reproduce by spores produced in sporangiaSpores are homosporousGive rise to bisexual gametophytesVascularUndergo alternation of generationsDominant Sporophyte GenerationGametophyte generation (prothallus)Includes ferns, whisk ferns, and horsetails
7 FernsAn ancient group of plantsVery diverse group
8 Parts of a Fern Rhizome – horizontal underground stem Frond- megaphyll leafFiddlehead – young, tightly coiled frondSporangia – spore casesSori – clusters of sporangia on bottom side of frond6th hr left off here!
14 Horsetails Have hollow, jointed stems Stems contain silica Wet, marshy habitatsGenera: Equisetophyta2nd Hour Left off Here!
15 Lycophytes Phylum Lycopodiophyta Remember: “I Like-o-Fight with Clubs & Spikes, & go for the Quill”Seedless – Reproduce by sporesSpores can be heterosporous2 types of n spores –megaspores (form a female gametophyte)microspores (form a male gametophyte)VascularDominant Sporophyte generationIncludes Club Mosses, Spike Mosses, & Quillworts6th Hour left off here
16 3 Groups of Lycophytes Club Moss True roots Rhizomes & erect or trailing aerial stemsSmall, scale-like microphyll leaves1st Hour1st Hour Left off Here
17 3 Groups of Lycophytes 2. Spike Moss Long, creeping rhizomes Typically branch dichotomouslyRoots branch dichotomouslyOverlapping, scale-like microphylls2nd Hour Left off here!Resurrection Plant
18 3 Groups of Lycophytes 3. Quillwort Underground corm A short, swollen underground stemCylindrical, quill-like microphyll leafsRoots
19 Ecological & Economic Impacts Ferns & LycophytesHelp form soilPrevent soil erosionBranching underground rhizomes and roots or rhizoids hold soil in placeCoal depositsFormed by remains of ancient fernsPowered Industrial Revolution of 19th CenturyUsed today to produce electricity