Page 123 - Ultimate Visual Dictionary (DK)

HORSETAILS, CLUBMOSSES, AND FERNS
SPORE PRODUCTION IN FERN Sporangium LIFE-CYCLE OF FERN
Bracken (spore-producing Annulus
(Pteridium Apex of structure) (ring of cells
pinnule
aquilinum) Spore around sporangium) Pinna (leaflet)
Sporangium Pinnule (leaflet
(spore-producing
Pinnule structure) of pinna) Frond
(leaflet (leaf)
of Spore inside Rolled
pinna) dehisced immature
(split open) frond
sporangium
Abaxial Pinnule SPOROPHYTE Rhizome
(lower)
(leaflet Placenta
surface of of pinna)
pinnule
Indusium
Sorus
Midrib of (group of (flap
protecting
pinnule sporangia) Midrib of pinnule sorus) Sorus
(group of
MICROGRAPH OF SPORANGIA ON
MICROGRAPH OF LOWER SURFACE Sporangium sporangia)
LOWER SURFACE OF FERTILE (spore-producing structure)
OF FERTILE PINNULE
PINNULE
SECTION THROUGH MATURE PINNULE
Midrib Apex of frond (leaf)
FERN of pinna Sporangium
Male fern (leaflet) splits and
(Dryopteris filix-mas) Annulus releases spores
ruptures
Pinna at weak
(leaflet) point
Spore
RELEASE OF SPORES
FROM SPORANGIUM
Spore Filament
develops
into
Rhizoid
Pinnule prothallus
(leaflet of
pinna) GERMINATION OF SPORE
Archegonium
Frond Antheridium (female sex
(leaf) (male sex organ)
organ)
Prothallus
(free-living
Young frond gametophyte) Rhizoid
(leaf) GAMETOPHYTE PRODUCES GAMETES
Young frond
Rachis (leaf) rolled
(main axis of and covered
pinnate leaf) by ramenta Antheridium
(male sex Oosphere
organ)
Base of Ramentum (female
Sclerenchyma old dead (brown scale) gamete)
Vascular (strengthening tissue) frond (leaf)
bundle Rhizome Antherozoid
Phloem (male gamete) Archegonium
Vascular swims to (female sex organ)
Xylem tissue oosphere FERTILIZATION
Primary leaf
of growing Remains of
sporophyte gametophyte
Epidermis
(outer layer
Parenchyma of cells)
(packing tissue)
MICROGRAPH OF CROSS-SECTION Adventitious root FERTILIZED OOSPHERE GROWS
THROUGH FERN RACHIS INTO NEW SPOROPHYTE PLANT
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