SCIENCE 4TH MID

• Ferns do not flower in order to reproduce. Instead, reproduction is completed in the presence of spores.
• There are two distinct generations in their life cycles: the sporophyte and the gametophyte generations.

  This is also referred to a alternation of generations.
• The first stage is the gametophyte generation.
• Gametophyte Generation - is almost always short-lived and is not easily seen.
• If the spores land in a suitable environment, these germinate and grow into small heart-shaped plants called prothallus or fern gametophyte.
• The prothallus is a green, photosynthetic structure that is one cell thick, usually heart or kidney-shaped.
• The prothallus is 3-10 mm long and 2-8 mm broad.
• The rhizoids anchor the small plant to the soil and absorb water and nutrients for the growth of the plant.
• The antheridium is the male sex organ, the archegonium is the female sex organ.
• The gametes that are produced in the antheridium and archegonium through meiosis (reductional cell division) carry one set of chromosomes.
• Moss leaves also have a waxy covering called cuticle.
• The foot transfers nutrients from the maternal, leafy gametophyte to the sprophyte.
• The second distinct generation in the life cycle of ferns is the sporophyte generation.