Alternation of generation in mosses e.g funaria, polytrichum

– begins with egg producing archegonia and
– sperm producing antheridia
– both are located within leafy portion of gametophyte
– antheridia mature and rupture
– release haploid antherozoid
– neck of archegonia open
– haploid egg cell located at the base of archegonia
– antherozoid swim into archegonia
– fertilization takes place
– zygote (diploid) is formed
– this group into the sporophyte
– sporophyte reduce and dependent on gametophyte
– sporophyte consist of foot, seta and capsule (sporogonium) bears spores
– haploid spores formed at meiosis
– these mature and are released when capsule ruptures
– carried by wind current to suitable substrate
– germinate to form protonema (haploid)
– protonema grows into gametophyte (haploid)
– gametophyte bears male and female gametangia (antheridia and archegonia)
– cycle continues/alternates

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