Bibliography

http://www.britannica.com/EBchecked/topic/250316/gymnospermhttp://www.hcs.ohio-state.edu/hcs300/svp2.htmhttp://www.facebook.com/l.php?u=http%3A%2F%2Fwww.bio.umass.edu%2Fbiology%2Fconn.river%2Fmosses.html&h=9906b5e863ab5ce0cf8bc2a900a2affchttp://www.cavehill.uwi.edu/FPAS/bcs/bl14apl/bryo1.htm
http://arnica.csustan.edu/Boty1050/Vascular/vascular_plants.htm
http://tolweb.org/angiosperms
http://mojavedesert.net/glossary/gymnosperm.html
http://bryophytes.plant.siu.edu/bryophytes.html
http://www.youtube.com/watch?v=35vPjdTNRU0

Introduction

Plant scientists recognize two kinds of land plants, namely, bryophytes, or nonvascular land plants and tracheophytes,or vascular land plants.

Non-Vascular Plants

Non-vascular (lower) plants

1. Lack true conducting tissues, leaves and roots. Since they lack elaborate conducting tissues they are relatively small

2. Require water for fertilization so they must grow in moist or seasonally moist habitats

Mosses

Mosses are very small green plants. Typically they consist of a stem not much thicker than a thick hair, densely covered with leaves maybe 1/16th or 1/8th of an inch long. Often moss stems branch and rebranch. Usually many mosses grow together forming a thick green carpet. Sometimes this carpet is no larger than a dime, but other times it may cover areas several feet in diameter.

Pterophyta

The Pterophyta are the second largest division of the plant kingdom. There are 20,000 species of ferns compared to about 250,000 flowering plants alive today. Most ferns are herbaceous plants such as Polypodium virginianum (right) which grows in Ohio on damp rockfaces.

Vascular Plants

Vascular (higher) plants:

1. Have true conducting tissues (xylem and phloem), leaves, stems and roots

2. Constitutes the majority of plants

Gymnosperms

Gymnosperms- (“naked seeds”) A type of vascular plants which is more primitive than the flowering plants (angiosperms). Gynosperms commonly have seeds within a cone.

Angiosperm

The angiosperms, or flowering plants, are one of the major groups of extant seed plants and arguably the most diverse major extant plant group on the planet, with at least 260,000 living species classified in 453 families (Judd et al., 2002; APG II, 2003; Soltis et al., 2005). They occupy every habitat on Earth except extreme environments such as the highest mountaintops, the regions immediately surrounding the poles, and the deepest oceans.