BISC 337 Lecture Notes - Lecture 6: Non-Vascular Plant, Protonema, Bryidae

• School: Simon Fraser University
• Department: Department of Humanities Biological Sciences
• Course: BISC 337
• Professor: Aubrey Pearson

Document Summary

Lack of vascular tissue consisting of xylem and phloem. Bryidae (true mosses) have rudimentary conducting tissue: hardron = conducts water, analogous to xylem, leptom = conducts nutrients, analogous to phloem. Start with phylum: bryophytes -> bryophyta (mosses) -> class sphagnidae (peat moss) Three distinguishing features of sphagnidae: 1) disk or rosette-shaped protonema, protonema = thread-like chain of cells that grows from germinating spores in mosses (filaments of chlorophyll-rich cells) which accumulates hormones to push for further growth. Jan 20: 2) gametophyte has a distinctive bushy leaf form, clusters of branches, densely tufted near tip, appearance is like a mop, 3) has excellent water holding capacity. Contain dead empty cells surrounded by living cells: pores and spiral thickenings in empty dead cells, large empty cells that fill with water, living green cells with discoid chloroplasts, may also contain reddish pigment. A 2ox sphagnum dressing can hold up to 2lb of water. Antheridia and archegonia arise at tips of apical branches.