Dec 31, 2015
Bryophytes
• Oldest plants ~400 million years old• Autotrophic, multicellular eukaryotes• 18,600 species• Mosses, Liverworts, Hornworts
Bryophytes• Nonvascular- cannot transport water or nutrients
or starch• No true leaves, roots, stems- • Small <20 cm• 3 features of land plants– Cuticle– Cellular jacket around gametes– Large gametophytes separate from sporophyte
Mosses
• 10, 000 species• Grow in moist areas- water still needed for
sperm to move to egg• Peat moss- used for fuel• Rhizoids- root-like structures used for
attachment to soil
Mosses
Hornworts
Liverworts
Bryophytes life cycle
Seedless Vascular plants• Next group to evolve further features for
life on land• Xylem and Phloem- move water and sugars
throughout the plant• 13, 000 species• True roots, leaves, stems- rhizomes• NO SEEDS but use SPORES• Large sporophyte
Seedless vascular
• 4 major divisions• Pterophyta- ferns• Psilotophyta- whisk ferns• Lycophyta- club mosses• Sphenophyta- horsetails
Lycophyta
• 1,100 species• Club mosses- still need the water to
reproduce• Commonly called “mini pines”• Cone-like structures called a strobilus contain
spore producing leaves
Club Mosses
Psilotophyta
• Whisk ferns- not true ferns• Rhizomes- short branched, horizontal
absorptive stems that grow underground• Reduced leaves• Photosynthetic branches
Psilotophyta
• Whisk ferns- not true ferns• Rhizomes- short branched, horizontal
absorptive stems that grow underground• Reduced leaves• Photosynthetic branches
Whisk Ferns
Horsetails
Pterophyta
• Ferns- 12,000 species• Largest and most diverse group• Mostly tropical• 1 cm across to 25 m tall• Vascularized rhizomes give rise to roots and
leaves• Sporangia on leaves release spores
Ferns
• Stomata in leaves• Life cycle dominated by sporpohyte (1st time
we see this)• Eggs and sperm produced- need water• Immature leaves are called fiddleheads-
mature leaves- fronds
FernsSorus- clusters of sporangia- spore producing tissue
Fern life cycle
Tree fern