Seedless Plants C9L2

The 3 Major categories of plants

Non-vascular plants Division Bryophyta moss liverwort hornwort

Non-vascular plants These plants are called bryophytes. Phylum Bryophyta (means “mosslike plant”)

Non-vascular plants Water and other materials are transported by diffusion. Fairly short.

Non-vascular plants Sometimes have parts that look like roots, stems, or leaves, but there is no vascular tissue so they don’t have roots, stems, or leaves. Live near water or shady places.

Just because a plant has the word “moss” in its name, doesn’t make it moss. Examples … Irish moss (algae) Reindeer moss (lichen – fungus & algae Spanish moss (flowering plant)

Irish Moss

Reindeer Moss

Spanish Moss

Parts of a moss plant leafy shoot- a slender stalk with leaflike structures; each of the tiny leaflike structures on moss is 1 cell layer thick

Rhizoids are structures that anchor a nonvascular seedless plant to a surface.

Parts of a moss plant Leafy shoot Leaflet Rhizoids

Moss Leafy Shoot

Alternation of Generations Life Cycle of Moss Alternation of Generations Sporophyte Generation: produces spores (asexual) Gametophyte Generation: produces gametes (sexual)

Life Cycle of Moss Gametophyte Generation The top of the male gametophyte bears the antheridia which produces sperm The top of the female gametophyte has one or more archegonia which contains the ova Sperm swim from the antheridia to the archegonia and fertilizes an ovum (zygote)

Life Cycle of Moss Sporophyte Generation Zygote grows into a stalk with a capsule which produces spores When mature the cap comes off and spores disperse Spore grows when environmental conditions are right First grows into a cellular filament called a protonema Protonema then forms the leafy shoots and rhizoids

Life Cycle of Moss Protonema

Moss

Moss Capsule

Marchantia – a common liverwort with a y-shaped thallus Liverworts “Liver Plant” Marchantia – a common liverwort with a y-shaped thallus Have splash platforms which look like little umbrellas

Benefits of Mosses Help to replenish the soil Help to prevent soil erosion Peat moss or Sphagnum is used by gardeners to pack plants for shipment and in Iceland and other northern regions it is used as fuel Has been used for surgical dressing

Sphagnum Sphagnum is a genus of between 1510 and 3500 species of mosses, commonly called peat moss due to its prevalence in wet habitats where it contributes to the formation of peat bogs and mires.

Division Pteridophyta Vascular Plants Without Seeds Ferns

Ferns: nonflowering vascular plants Spore-bearing leaves Horizontal undergound stems 1-2 feet tall Tropical ferns may grow as tall as 60 ft. with fronds 12-14 ft. Some are epiphytes

Parts of a fern: Fronds – leaves Rhizome – a creeping or underground stem, which produce roots Sori – groups of spore-bearing sporangia (means “a heap”)

Fern Sori Sori may be round, kidney-shaped, oblong, linear, curved, or star-shaped.

Sporophyte Generation of Ferns A new fern’s life cycle typically begins in July with the appearance of sori on the undersurface or along the margins of a frond.

Sporophyte Generation Sori appear on the underside of a frond. Sori first open and discharge millions of spores.

Gametophyte Generation Spore develops into a tiny green, heart-shaped structure called a prothallus. Seldom seen, only 1 cell layer in thickness.

Gametophyte Generation The underside of the prothallus develops archegonia and antheridia Antheridia near the point (sperm) Archegonia at notched end (ova)

Gametophyte Generation Sperm are released from the antheridia and swim to the ovum at the bottom of the archegonia.

Sporophyte Generation Zygote matures and sends the first leaf up and the first root down. The first leaf is often a fan-shaped blade. The second leaf is usually a fiddlehead, a coiled young leaf. Some fiddleheads are edible and used in salads.

Fern Alternation of Generation Facts Ferns usually require 3-7 years to reach reproductive maturity. Fern plants (sporophytes) live for several years and produce new fronds each year Dominant generation: Sporophyte

Fern Alternation of Generation Facts Protellia (gametophytes) only live 3-7 weeks, in which time they produce the archegonia and antheridia. Dominant generation: Sporophyte

Other seedless vascular plants: club moss, whiskfern & horsetail

club moss club mosses: (also called "ground pine" because they grow along the ground in temperate regions)

horsetail all but one group have become extinct the epidermis contains a glasslike substance (silica) which feels very rough to the touch called "scouring rushes" - used for scouring pots and pans before scouring powder and pads were known.

Horsetail (cont.) Horsetails have small leaves growing in circles around the stems. Horsetail stems are hollow, and the tissues contain silica, a mineral in sand, that makes them abrasive. S. Solum/PhotoLink/Getty Images