characterized by ornamentation (reticulation, ridges,
spines, etc.), and some taxa may have an outer wall called
perine.
Pollen grains are produced by seed plants or spermatophytes, which involve reproduction on the sporophyte
instead of reproduction with alternation of generations
(sporophyte and gametophyte) as for seedless plants.
Spermatophytes include the flowering plants or angiosperms (magnoliophytes) and the gymnosperms
(pinophytes or conifers, ginkgophytes, gnetophytes,
cycadophytes). The pollen grains contain the male reproductive body, which is protected by the exine, an envelope
composed of sporopollenin. Pollen is formed in the anther
of flowers or in the male cone of gymnosperms. When
mature, pollen grains are blown away by wind or carried
by animal vectors to fertilize either the ovule in the pistil
of flowers or the female cones of gymnosperms. The fertilization of the ovule also called pollination can be referred
to as anemophilous or entomophilous in the case of pollination from wind or insects, respectively. In general,
anemogamous plants produce more pollen grains than
entomophilous plants.
Pollen grains of gymnosperms are generally distinguished on the basis of their shape, subspherical with or
Palynology (Pollen, Spores, etc.), Figure 2 Photographs of common spore and pollen taxa. The magnification is the same for all
photographs and the scale shown in a is 10 mm. (a–f) Photographs of spores from seedless plants: trilete spores of Sphagnum, which
belongs to bryophyte (a); trilete spores of the pteridophyte Osmunda (b); trilete spores of the lycopodiophytes Lycopodium (c, d) and
Selaginella (e); monolete spore of undetermined pteridophyte (f). Photographs of pollen grains from conifers: bisaccate pollen grain
of Picea (g) and Pinus (h) and vesiculate pollen of Tsuga (i). (j–s) Photographs of pollen grains from angiosperms: Cyperaceae (j),
Poaceae (k), Betula (l), Alnus (m), Chenopodiaceae (n), Artemisia (o), Tubiflorae (p), Quercus (q), Salix (r), and Rosaceae (s).
PALYNOLOGY (POLLEN, SPORES, ETC.)
655
spines, etc.), and some taxa may have an outer wall called
perine.
Pollen grains are produced by seed plants or spermatophytes, which involve reproduction on the sporophyte
instead of reproduction with alternation of generations
(sporophyte and gametophyte) as for seedless plants.
Spermatophytes include the flowering plants or angiosperms (magnoliophytes) and the gymnosperms
(pinophytes or conifers, ginkgophytes, gnetophytes,
cycadophytes). The pollen grains contain the male reproductive body, which is protected by the exine, an envelope
composed of sporopollenin. Pollen is formed in the anther
of flowers or in the male cone of gymnosperms. When
mature, pollen grains are blown away by wind or carried
by animal vectors to fertilize either the ovule in the pistil
of flowers or the female cones of gymnosperms. The fertilization of the ovule also called pollination can be referred
to as anemophilous or entomophilous in the case of pollination from wind or insects, respectively. In general,
anemogamous plants produce more pollen grains than
entomophilous plants.
Pollen grains of gymnosperms are generally distinguished on the basis of their shape, subspherical with or
Palynology (Pollen, Spores, etc.), Figure 2 Photographs of common spore and pollen taxa. The magnification is the same for all
photographs and the scale shown in a is 10 mm. (a–f) Photographs of spores from seedless plants: trilete spores of Sphagnum, which
belongs to bryophyte (a); trilete spores of the pteridophyte Osmunda (b); trilete spores of the lycopodiophytes Lycopodium (c, d) and
Selaginella (e); monolete spore of undetermined pteridophyte (f). Photographs of pollen grains from conifers: bisaccate pollen grain
of Picea (g) and Pinus (h) and vesiculate pollen of Tsuga (i). (j–s) Photographs of pollen grains from angiosperms: Cyperaceae (j),
Poaceae (k), Betula (l), Alnus (m), Chenopodiaceae (n), Artemisia (o), Tubiflorae (p), Quercus (q), Salix (r), and Rosaceae (s).
PALYNOLOGY (POLLEN, SPORES, ETC.)
655