k: plantae div: sphenophyta “horsetails or scouring rushes” n 1. silica in cell walls. n 2....
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K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
1. Silica in cell walls. 2. Leaves microphyllous; small and scalelike; form whorls at
nodes. 3. Vegetative and fertile shoots. 4. Large sporophyte (2n) & small gametophyte (n) - both independent. 5. Extensive rhizomes with roots that branch irregularly. 6. All branching (leaves & roots) whorled at nodes. 7. Growth from the base of each segment (intercalary). 8. Are homosporous.
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
Intercalary meristem– adds length to the internodes
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
*All of the silicified cells are in the epidermis. *Stomates of epidermis sunken in E. hymanale. *Carinal canals for water conduction. *Central canal and vallecular canals for gas exchange. *Root is protostelic * Stem is eustelic at internodes Stem is siphonstelic at nodes
Endodermis
– outside layer around stele
Pericycle– single cell layer just inside of endodermis– gives rise to branch roots
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
Stomate - guard and subsidiary cells
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
Reproduction: homosporous
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
Reproduction: homosporous sporangiophore and sporangia
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
Reproduction: homosporous tapetum and tapetal plasmodium
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
Reproduction: homosporous green spores germinate quickly.
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
Reproduction: homosporous spores with elators
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
Reproduction: homosporous green spores germinate quickly.
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
Reproduction: homosporous meiosis spores (n) germinate ----------> gametophyte (n)
2 types of gameophytes: male or female - dioecious Or female --> archegonia --> archegonia & antheridia (protogynous)
K: Plantae Div: Sphenophyta“horsetails or scouring rushes”
Reproduction: homosporous fertilization --> zygote (2n) --> sporophyte (2n)
K: Plantae Div: Psilophyta“Whisk Ferns”
Evolved during the late Devonian Period (approx. 375 mya)
K: Plantae Div: Psilophyta“Whisk Ferns”
1. Plant Body (2n) composed of thin dichotomously branched aerial stems and rhizomes with ridges and pentagonal in x-section.
2. No true roots but have rhizoids with micorrhiza.
K: Plantae Div: Psilophyta“Whisk Ferns”
1. Plant Body (2n) composed of thin dichotomously branched aerial stems and rhizomes with ridges and pentagonal in x-section.
2. No true roots but have rhizoids with micorrhiza. 3. Bears small leaf-like appendages, or prophylls.
K: Plantae Div: Psilophyta“Whisk Ferns”
1. Plant Body (2n) composed of thin dichotomously branched aerial stems and rhizomes with ridges and pentagonal in x-section.
2. No true roots but have rhizoids with micorrhiza. 3. Bears small leaf-like appendages, or prophylls. (no vascular tissue but leaf traces) 4. Spores (n) are produced in trilobed structures on the tips of
short branches called synangia.
K: Plantae Div: Psilophyta“Whisk Ferns”
4. Spores (n) are produced in trilobed structures on the tips of short branches called synangia.
tapetal plasmodium sporangial wall
K: Plantae Div: Psilophyta“Whisk Ferns”
Psilophyte spores (n) are kidney-shaped.
K: Plantae Div: Psilophyta“Whisk Ferns”
Psilophyte spores (n) are slow to develop into monoecious gametophytes (n).
archegonia
K: Plantae Div: Psilophyta“Whisk Ferns”
Psilophyte spores (n) are slow to develop into monoecious gametophytes (n).
antheridium
K: Plantae Div: Psilophyta“Whisk Ferns”
Development from the fertilized egg (zygote 2n) proceeds in the archegonium.
K: Plantae Div: Psilophyta“Whisk Ferns”
Eventually the young sporophyte (2n) becomes the mature plant body (2n).
K: Plantae Div: Psilophyta“Whisk Ferns”
Stem and rhizome development: immature stem tip - promeristem, protoderm, ground
meristem, procambium
K: Plantae Div: Psilophyta“Whisk Ferns”
Mature stem -
K: Plantae Div: Psilophyta“Whisk Ferns” Genus: Tmesipteris