BIOL108 Lecture Notes - Lecture 12: Microspore, Pollen Tube, Microsporangia

• School: University of Alberta
• Department: Biology (Biological Sciences)
• Course: BIOL108
• Professor: Lien Luong

Document Summary

Biol 108 - lecture #12 - bryophytes and vascular plants. Bryophytes (nonvascular plants: not a monophyletic group, dotted lines indicate the uncertainty of relationships of the phyla, thin, ground hugging plants. Doesn"t allow it to go to the top. Gets nutrients via diffusion: characteristics of bryophytes. Haploid gametophytes are most dominant phase of life cycle. Diploid sporophytes are smaller (only part of the time is there) Sperm swim through water film to fertilize eggs. **rely on presence of water to reproduce** Not yet fully terrestrial: typical life cycle. Here, the sporophyte is dependent on the gametophyte. The dead hollow cells (tracheids) act as water pipes. Roots and leaves ====> rest of plant. Microphylls: one strand of vascular tissue - small. Adapted the sporollenin walls for the sporangia. Didn"t have to depend on gametophyte anymore (reverse of moss: phylum lycophyta (~1200 species) Quillworts, club mosses, spike mosses: phylum pterophyta (~12 000 species) Had way more diversity: characteristics of seedless vascular plants.