Jumat, 14 Februari 2014

Non-Vascular Plants

Non-Vascular Plants

The group of plants which is included in non-vascular plants is moss (Bryophyte). Bryophytes are mosses that are often found in damp or wet places.
Do you often look at none rocks or walls in damp places and notice that the rocks or walls have turned green? If you observe them carefully, you will know that the green color is moss.
Moss has a stem and leaves which are very simple but has no vascular tissue (xylem and phloem). Moss has a structure which is similar to simple roots which is called rhizoid.

The characteristics of a moss are follow :

1. Moss leaves do not have leaf veius.

2. It does not have true roots, only rhizoid as sucker of food substance. Rhizoid is compound of a layer of imperfect time.

3. The stem does not have vasculat bunle yet; there are xylem and phloem.

4. Reproduce with spores. Spores are formed inside the sporogonium (sprebox).

5. It is mono sexual. It undergoes hereditary cycle (gametophytic and sporophytic phase). What is knows as moss is the gametophyte (gamete producing plant or sexual organ), while the sporophyte (spore-producing plant) is not clearly visible.

6. The gametophyte of moss is haploid (n), while the sporophyte is diploid (2n).

The classification of Bryophytes has been developing from fine to time. Eicher (1883) divided Bryophytes into two classes, Hepatical and Musci.
The above classification was apparantly still developed for further. For example, Howe (1899) the order of Anthocerotales in one class, making Bryophytes coursift of three classes, Hepatical, Anthocerotae, and Musci.

The three classes of Bryophytes are follows :

1. Hepar Moss (Hepaticae)
2. True Moss ( Musci)
3. Horn Moss (Anthocerotae)