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  • Short Answer. Comment on the lifecycle and nature of a fern prothallus.
    Nature of Fern Prothallus: The prothallus represents the haploid gametophytic generation It is a multicellular, independent, photosynthetic form that lives for a short duration The prothallus needs a cool, damp, and shady place to grow Due to its requirement of water for fertilization, pteridophytes are restricted to narrow geographical regions
  • A prothallus isA structure in pteridophytes formed before the thallus . . .
    The prothallus is generally monoecious as it bears both male and female sex organs i e antheridia and archegonia respectively or it may be dioecious if male and female sex organs are present on different plants
  • Prothallus isGametophyte, monoecious and autotrophic present in . . .
    The prothallus is monoecious (ferns) or dioecious (Selaginella) It bears sex organs i e , male antheridia and female archegonia It bears sex organs i e , male antheridia and female archegonia They are present ventrally
  • A prothallus is - Toppr
    Prothallus is autotrophic, independent and free-living in nature The male and female sex organs can develop either on a single prothallus (monoecious) or on a different prothallus (dioecious) Hence, a prothallus is a gametophyte and free-living structure formed in pteridophytes
  • Prothallus of the fern producesSporesConesBoth A and BGametes - Toppr
    The prothallus is the fern gametophyte It is a green, photosynthetic structure that is one cell thick, usually heart or kidney shaped, 3–10 mm long and 2–8 mm broad Prothallus of fern produces male and female gametes which after fertilization give rise to dioploid sporophyte which produces spores
  • The prothallus of fern is - Toppr
    Prothallium or prothallus is usually the gametophyte stage in the life cycle The prothallium develops from a germinating spore It is a short-lived structure, typically 2-5 millimeters wide, with a number of rhizoids (root-like hairs) growing underneath, and the sex organs: archegonium (female) and antheridium (male)
  • Fern prothallus is developed from - Toppr
    Prothallium, or prothallus is usually the gametophyte stage in the life cycle The prothallium develops from a germinating spore It is a short-lived and inconspicuous heart-shaped structure typically 2-5 millimeters wide, with a number of rhizoids (root-like hairs), growing underneath, and the sex organs: archegonium (female) and antheridium
  • The prothallus representsGametophyte of fernSporophyte of . . .
    This is the gametophyte stage The prothallus produces a antheridia andarchegonia These are exosphoric
  • Prothallus of Dryopteris is a . . . . . . . . . . . . . . . . . It bears archegonia on . . .
    The spore germinates into gametophyte known as prothallus Prothallus has archegonia present on the ventral side Hence, the Prothallus of Dryopteris is a Gametophyte It bears archegonia on the ventral side So, the correct answer is 'Gametophyte, ventral'
  • In pteridophytes, prothallus produces - Toppr
    In pteridophytes, spore is a haploid structure, which develops after meiosis of spore mother cell On germination, it gives rise to a green haploid prothallus (gametophyte) which is monoecious, i e , has both antheridia (male sex organs) and archegonia (female sex organs) in homosporous pteridophytes





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