LycoRepro-1

Lycopodium sp. with an upright Stem with Adventitious Roots emerging from the subterranean part of its Stem. Sporangia are be located in the axil of leaves. Axil refers to the angle formed between the upper surface of the leaf and the Stem. The Upper surface is called Adaxial. The Lower surface is Abaxial. (Ad = Towards; Ab = Away). Adaxial means the surface towards the stem. Abaxial means away from the stem. The Sporophylls may closely resemble Vegetative leaves. Immature Sporangia are Green (above) they turn Yellow as they mature and Open. Sporophylls can be organized into Terminal Cones or Strobili. In the image above and to the right the Sporangia are still adaxial. The Sporophylls are green and tightly closed until the Sporangia mature. Then, the Sporophylls turn yellow, & become reflexed upon maturation. The Sporangia open like those to the right. Lycopodium is Homosporous. The Spores contain a high concentration of Oil. They were used as flash powder during the early days of Photography. Oil is a good storage product. However, Lycopodium Spores are not adapted to endure long periods of dormancy. They must germinate quickly after they are shed. Lycopodium Spores: Tetrads are produced by Meiosis which converts 1 Diploid Cell into 4 Haploid Meiospores.	Sporangia are borne on the Leaves which are referred to as Sporophylls. Sporophyll from Lycopodium Note the Yellow Sporangia in the Axil of the Sporophylls above & below.
	Lycopodium with Cones or Strobili. *Microscopic view of Immature (left) & Mature (right) Lycopodium* Cones showing Sporophylls & Sporangia** Lycopodium Sporangium containing Tetrads of Spores SEM Photo of Lycopod Spore
Some species produce Photosynthetic Gametophytes. These are said to be Epiterrestrial (above ground). These need Light and Water in order to survive. They are also directly exposed to temperature and moisture perturbations in the environment. Two examples of Autotrophic Gametophytes are given below.

Some species produce Subterranean Gametophytes. These are Heterotrophic depend on Symbiotic relationships with Fungi in order to survive. Neither type of Gametophyte has Organs or Vascular Tissues!
Subterranean Gametophyte: Note the abundance of Rhizoids.	Ventral view of a Subterranean Lycopod Gametophyte with SEM. This photo was taken near the Meristematic Region of the Gametophyte. Note the Ventral Rhizoids. Antheridia and Archegonia are produced on the Dorsal side of the Gametophyte.
The Gametophyte does NOT have Stems Roots or Leaves. It probably lacks Vascular Tissues.
	Sperm are Biflagellate!
SEM image of a collapsed Antheridium and Sperm (red) from Lycopod Gametophyte. The Sperm Swim through an opening created by the cell that occupies the apex of the Antheridium.	Archegonia (Yellow) on the Gametophyte. Fertilization occurs when the biflagellate Sperm reaches the egg.