Wall Developments and Coordinated Cytoplasmic Changes in Spermatogenous Cells of Polytrichum (Musci)

1976 ◽  
Vol 79 (4) ◽  
pp. 466 ◽  
Author(s):  
D. J. Paolillo ◽  
M. Cukierski
Keyword(s):  
Spermatogenous Cells

Recovery of microtubules on the blepharoplast of Ceratopteris spermatogenous cells after oryzalin treatment

PROTOPLASMA ◽  
2008 ◽  
Vol 233 (3-4) ◽  
pp. 231-240 ◽  
Author(s):  
Kevin C. Vaughn ◽  
Andrew J. Bowling
Keyword(s):  
Spermatogenous Cells

scholarly journals Ultrastructure and Differentiation In Chara Sp. III. Formation of the Antheridium

1968 ◽  
Vol 21 (2) ◽  
pp. 255 ◽  
Author(s):  
JD Pickett-Heaps
Keyword(s):  
Endoplasmic Reticulum ◽  
Basal Cell ◽  
Outer Layer ◽  
Distinctive Pattern ◽  
Wall Deposition ◽  
Nodal Cell ◽  
Large Numbers ◽  
Cytoplasmic Microtubules ◽  
Spermatogenous Cells

The formation of the antheridium from an enlarged nodal cell is described. After a basal cell has been cut off, precisely oriented mitoses divide the antheridial cell initially into octants; then follow two periclinal divisions in each octant. The outer layer of cells become the shield cells, the middle form the manubria, and the inner capitula cells divide further to produce secondary capitula and ultimately the spermatogenous threads. The shield cells become compartmentalized during enlargement by ingrowths in the wall which finally form a very distinctive pattern. Microtubules are associated with the regions of wall deposition. Plastids in the shields accumulate large numbers of globuli, and this is probably associated with the orange pigmentation they acquire. Large amounts of material seem to be secreted into the antheridia by the manubria; this material is formed within large vesicles which are apparently discharged through the plasmalemma. In the young capitula, a characteristic, highly organized grouping of many cytoplasmic microtubules forms a band which appears to wind through the cytoplasm; its significance and functions are obscure. Presumptive "spherosomes" are present in large numbers in these and spermatogenous cells. The spherosomes and lipid-like inclusions are very frequently coated with membranes of the endoplasmic reticulum.

scholarly journals Localization of Ca++-containing antimonate precipitates during mitosis.

1980 ◽  
Vol 86 (2) ◽  
pp. 500-513 ◽  
Author(s):  
S M Wick ◽  
P K Hepler
Keyword(s):  
Mitotic Spindle ◽  
Divalent Cations ◽  
Structural Components ◽  
Mitotic Apparatus ◽  
Stomatal Complex ◽  
Complex Cells ◽  
Major Cation ◽  
Marsilea Vestita ◽  
Spermatogenous Cells

Intracellular bound Ca++ has been localized throughout mitosis and cytokinesis in two plant species by means of in situ precipitation with potassium antimonate and electron microscope visualization. Identification of Ca++ as the major cation precipitated was made by comparing solubility properties in water, EDTA, and EGTA of the intracellular deposits with respect to those of K+-, Mg++-, and Ca++-antimonate standards. In spermatogenous cells of the water fern, Marsilea vestita, and stomatal complex cells of barley, Hordeum vulgare, antimonate deposits have been found associated with the endoplasmic reticulum (ER), vacuoles, euchromatin/nucleoplasm, and mitochondria. The last contain a much higher density of precipitates in Marsilea than in Hordeum. Dictyosomes and the nuclear envelope of Marsilea also contain antimonate deposits, as do the plasmalemma, cell wall, and phragmoplast vesicles of Hordeum. Microtubule-organizing centers such as kinetochores and the blepharoplast of Marsilea do not stain. In spite of differences in associated antimonate between certain organelles of the two species, the presence of antimonate aong the ER throughout the cell cycle is common to both. Of particular interest are those precipitates seen along the tubules and cisternae of the extensive smooth ER that surrounds and invades the mitotic spindle in both species. The ability to bind divalent cations makes the mitotic apparatus (MA)-associated ER a likely candidate for regulation of free Ca++ levels in the immediate vicinity of structural components and processes that are Ca++-sensitive and proposed to be Ca++-regulated.

Annulate lamellae in spermatogenous cells of Lycopodium obscurum

1995 ◽  
Vol 73 (4) ◽  
pp. 552-556
Author(s):  
John R. Palisano ◽  
Karen Sue Renzaglia ◽  
Angel Renee Maden ◽  
Dean P. Whittier
Keyword(s):  
Endoplasmic Reticulum ◽  
Key Words ◽  
Cross Section ◽  
Plant Tissue ◽  
Cell Lineage ◽  
Annulate Lamellae ◽  
Nuclear Pores ◽  
Spatial Associations ◽  
First Time ◽  
Spermatogenous Cells

The existence of annulate lamellae is detailed for the first time in the ultrastructure of a plant flagellated cell lineage. In early spermatogenous cells of Lycopodium obscurum, annulate lamellae are abundant and located adjacent to either the nucleus or plastid. Individual organelles consist of 1–11 parallel cisternae bearing tightly compacted pores that are similar in size and substructure to nuclear pores. In cross section, the pores measure 95–130 nm in diameter. Frequently, endoplasmic reticulum is continuous with the annulate lamellae cisternae. The existence of annulate lamellae in Lycopodium extends the known distribution of these organelles to rapidly proliferating spermatogenous tissue of seedless plants. Moreover, spatial associations between annulate lamellae and plastids are reported for the first time in any plant tissue. Key words: Annulate lamellae, Lycopodium, plastid, "pteridophyte," spermatogenesis, ultrastructure.

scholarly journals Ultrastructure and Differentiation in Chara (Fibrosa) IV. Spermatogenesis

1968 ◽  
Vol 21 (4) ◽  
pp. 655 ◽  
Author(s):  
JD Pickett-Heaps
Keyword(s):  
Structural Changes ◽  
Chromatin Condensation ◽  
Ultrastructural Level ◽  
Flat Band ◽  
Cell Organelles ◽  
Microtubule Organization ◽  
Golgi Bodies ◽  
Unknown Significance ◽  
Almost All ◽  
Spermatogenous Cells

Spermatogenesis in Ohara is described at the ultrastructural level. A large nwnber of mitoses form spermatogenous threads, derived from the capitula inside the antheridiwn. Centrioles appear in the spermatogenous cells early as indistinct organelles that quickly become conspicuous. There is some evidence for the existenc of a procentriole. Centrioles are subsequently associated in a normal fashion with the mitotic spindle. Intracellular differentiation commences after mitosis ceases. The nucleus moves to one side of the cell; a flat band of manchette microtubules is soon formed near it. The microtubules, which increase in nwnber and elongate considerably, are inserted at one end into (and possibly extruded from) a densely staining, homogeneous inclusion, termed the manchette adjunct, which appears close to the centrioles. The centrioles, connected together by a spindle-shaped ciliary rootlet structure, move to the edge of the cell and start extruding flagella, which are covered in scales; another organelle, termed the vesicular adjunct and of unknown significance, appears near these centrioles. The manchette grows in length, and so asswnes a spiral course in the cell; plastids then line up along the microtubules next to the nucleus. While still interconnecting cells, the cytoplasm shrinks steadily. With further elongation of the manchette, the flagella apparatus moves away from the nucleus, and mitochondria also line up along the manchette tubules between them. Lipid (?) bodies move near the plastids, which steadily accumulate starch. Golgi bodies show marked structural changes during differentiation; they are initially associated with a profusion of various vesicles, and later lose their identity, as does the endoplasmic reticulwn which earlier interconnected cells through plasmadesmata. The nucleolus disappears, and later chromatin condensation gives the elongating nucleus an increasingly lamellate structure; finally these lamellae fuse to form a dense homogeneous nucleus. The cytoplasm continues to shrink, eliminating almost all cell organelles. The mature spermatozoid, tightly coiled in the cell, finally contains plastids and (lipoid) inclusions at one end, next to the dense, elongate nucleus, with linearly arranged mitochondria at the other end, and flagella inserted above the mitochondria. Manchette microtubules run the length of the organism as a flat band opposed to the nucleus and plastids, and finally as a tubular sheath partly enclosing the mitochondria. Four other tubules, possibly derived from a ciliary root structure, are also close to the mitochondria. The flagella are quite long by this stage. The observations are discussed in terms of the functions of cell organelles. In particular, it is suggested that centriolar movement in mitosis may be only one example of everal morphogenic movements associated with microtubule organization; their unction is in flagella formation, and not in synthesis of spindle, manchette, or other ytoplasmic microtubules.

Histones of spermatogenous cells in the house cricket

Chromosoma ◽  
1974 ◽  
Vol 46 (4) ◽  
pp. 397-419 ◽  
Author(s):  
Jerome S. Kaye ◽  
Rachel McMaster-Kaye
Keyword(s):  
House Cricket ◽  
Spermatogenous Cells
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