Exam III. 5 (Ferns)

two kinds of sporangia (mega and microsporangium)

megaspores and microspores

1. Megaspores (larger spores)—germinateà female gametophyteà archegonia (no antheridia)

2. Microspores (smaller spores)—germinateàmale gametophyteà antheridia

don't look fernlike

1) blade, pinnae (part of leaf floats on surface of water); sometimes, they have a long petiole

2) very common in s. part (FL in ditches, shell ponds, can't grow in really deep water; not in PA

                                                              i.      Reproducesà does not reproduce the same way a moss does in a way, but the reproductive structures do not really look alike

•                                                               i.      outside is very hard
• 2.      Each prob represents a pinna that is closed
• 3.      When it opensà gelatinous ring coming out (prob a pinna) each attached to it is a sorus
• 4.      Has an indusium; clear covering 

• 1.      Inside each round structure is a sporangia with both mega and microsporangium
• 2.      Large ring is the sorophore
• 3.      Mega: 32 and 64 spores
• a.      All develop into one megaspore
• 4.      In the micro: all develop into microspores

Sporophyte

• 1.      Microspore divides to produce male gametophyte with two antheridia (practically, whole male gametophyte is two antheridia)
• a.      One small: prothalial cell; basically doesn’t do anything; may be all that’s left of vegetative tissue
• b.      One large
• c.       Male has to swim to female

• 1.      Female gametophyte: one end of the female gametophyte bulges out and an archegonia forms from this end
• a.      Female gametophyte has to store all of the food the young sporophyte will need until its able ot begin photosynthesis

life cycles

homosporous: exosporal

heterosporous: gametophyte is a bit larger than spre

•                                                               i.      Gametophyte grows outside original spore wall
• 1.      As the gametophyte develops, it will be larger than original spore
• Typical

•                                                               i.      Gametophyte develops with spore wall around it
•                                                             ii.      Original spore wall would be at the neck
•                                                           iii.      Tiny bit larger, but not by much

• a.      Put in gardens
• b.      Industrially: not
• c.       Edible fiddlehead