Nonvascular Plants Caitlin Anderson

History The first land plants were nonvascular. Started appearing about 460 million years ago. Ancestor is green algae. They used to all be classified under Bryophyte, but now there are three divisions.

How they are similar to other Plants All plants need: Water An energy source (mostly the sun) Spreading out of young plants to eliminate competition with parent plants

Characteristics Lack Vascular tissues Move water by osmosis and diffusion Grow only 1-2 cm high Grow in large groups Don’t produce seeds or flowers Not typical plant stems or leaves Rhizoids instead of roots (they don’t absorb water or nutrients) No stomata

Reproducing Sexual and Asexual Sexual is more common Gametes are formed within gametangia Males’ have antheridium and make flagellated sperm A female has archegonium and makes one egg Water is needed for the sperm to reach the egg (rainwater or dew usually works)

continued The egg is fertilized and the diploid zygote splits by mitosis and turns into an embryonic sporophyte. This grows into a long stalk that stays attached to the female plant. A little capsule, sporangia, forms at the end and haploid spores are created by meiosis here. The spores are dumped out andeventually grow into mature plants. http://www.coolschool.ca/lor/BI11/unit7/U07L02.htm

Alternation of generations Alternation of generations- the cycle in which a plant creates two multicellular generations Diploid generation is called the sporophyte Haploid generation is called the gameophyte The gameophyte is the dominant generation in nonvascular plants The sporophyte depends on it for support

Bryophyta Mosses Most common nonvascular plants At least 10,000 species Some vascular tissue The sporangia is more complex than other plants Use each other to stay standing Have “stems” and “leaves” that are similar to vascular plants

continued Seven types of mosses More than 95% of mosses are Bryidae Andreaeidae Sphagnidae Tetraphidae Polytrichidae Buxbaumiidae Bryidae Archidiidae More than 95% of mosses are Bryidae

Sphagnum fuscum Tayloria mirabils Holomitrium crispulum

Hepatophyta Liverworts (hepatics) Around 8,000 different species About 1mm to 50mm Simplest plants Coil shaped sporangia Can form gemmae cups that hold cells that are released with rain to form new plants (asexual reproduction)

continued Ancient people thought they cured diseases of the liver Often confused with Hepatica plants because of the hepatics name. Two types: leafy and thallose Thallose is more common

Leafy Liverworts About one cell thick Easily identified as mosses Two or more sections Two rows of leaves usually A third row of smaller leaves often occurs (only visible by microscopes)

Thallose Liverworts No stem-leaf structure at all Surface is like a flat plate Can be several cells thick Can be divided into sections that vary in size Some have pores

Metzgeria furcata Tritomaria quinquedentata Conocephalum conicum

Anthocerophyta Hornworts About 100 species Have one Chloroplast per cell Hornworts get the name from the sporophytes Look similar to thallose liverworts

Commonly found Damp and shady areas Rocks Trees Near rivers Mostly wet regions

In Our Area Floating Liverworts and Umbrella Liverworts are very common in Minnesota Hornworts are rare in Minnesota St. Paul and Minneapolis Near White Bear Lake, Lake Calhoun, Lake Osakis, and Alexandria

Moss in Minnesota Little Saw Moss Bud-headed thread moss Egg-leaf true moss Bug-on-a-stick moss Hair-pointed thread moss Mowed mosquito moss Pigmy plume moss Extinguisher moss Cave moss Red twisted bog moss Cushion peat moss Shortleaf chalk moss Swan moss And more

Why Nonvascular Plants are Important They are first plants to colonize a region. Once mosses die, they decompose and create soil for new plants. They can be food for some animals. Peat mosses can be used by humans for fuel.

Other info They help indicate how pure an environment is. They are very sensitive to air and water pollution. That is why they are more common in country areas. Mosses are often used in decorating a garden. They are so small that they don’t have much impact on their surroundings.

Questions A. Thallose, Musky, Bryophytes B. Leafy, vascular, moss 1. What are the three divisions of nonvascular plants? A. Thallose, Musky, Bryophytes B. Leafy, vascular, moss C. Bryidae, Sphagnidae, Hepatica D. Bryophyta, Anthocerophyta, Hepatophyta   2. What is the most common type of moss? A. Mossy B. Buxbaumiidae C. Archidiidae D. Tetraphidae E. Bryiade 3. What is not true about liverworts? A. There are two types B. Ancient people thought they could cure diseases of the heart C. They are part of the Hepatophyta group D. Often confused with the Hepatica

more 4. What is true about alternation of generations? A. Gameophytes are always dominant B. Sporophytes are always dominant C. The gameophyte is dominant in nonvascular plants D. The gameophyte is dominant in vascular plants 5. What nonvascular plants are found in Minnesota? A. Lots of hornworts, umbrella and floating liverworts, and no mosses B. Few hornworts, umbrella and floating liverworts and, tons of mosses C. Few hornworts, puddle and sinking liverworts, and a few mosses D. There are absolutely none in Minnesota

The last few   6. Which kind of nonvascular plant is considered the simplest in structure? A. Liverworts B. Mosses C. Bryiade D. All of the above E. None of the above 7. Explain how nonvascular plants differ from vascular plants 8. Explain briefly how plants reproduce

Resources http://www.hiddenforest.co.nz/bryophytes/liverworts/intro.htm files.dnr.state.mn.us/input/rules/ets/mosses.pdf http://www.bryology.org/bryodesc.html http://www.cartage.org.lb/en/themes/Sciences/BotanicalSciences/ClassificationPlants/Cryptogamia/Bryophyta/Nonvascular/nonvascular.htm http://academickids.com/encyclopedia/l/li/liverwort.html http://www.sparknotes.com/101/biology/the_evolution_and_diversity_of_land_plants/nonvascular_plants.html