CYTOLOGIA
Online ISSN : 1348-7019
Print ISSN : 0011-4545
Volume 49 , Issue 1
Showing 1-29 articles out of 29 articles from the selected issue
  • K. S. Yadava, A. K. Singh, H. C. Arya
    1984 Volume 49 Issue 1 Pages 1-9
    Published: March 25, 1984
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Twenty four species and varieties of Cucumis were analysed meiotically. Out of these four species namely C. pustulatus, C. membranifolius, C. meeusei and C. heptadactylis were found to be natural polyploids (4x). Normal meiotic behaviour in diploid species led to the conclusion that basic chromosome complement was the same. Three gametic numbers i.e. 7, 12 and 24 were reported. Gametic number, 12, found in most of the species was considered as primitive base number and 7 and 24 as derived ones. During analysis of natural polyploids, two species namely, C. pustulatus and C. membranifolius were found to be allopolyploid on account of regular formation of 24 bivalents. On the other hand, few quadrivalents recorded in C. meeusei and C. heptadactylis pointed out their allo- or segmental polyploid nature. The observations suggested the dominant role of polyploidy in species differentiation of the genus Cucumis.
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  • Atef S. Soliman, Mohamed A. El-Sahrigy
    1984 Volume 49 Issue 1 Pages 11-20
    Published: March 25, 1984
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Morphological and cytological studies were conducted in Alexandria, Egypt with eight diploid and tetraploid Aegilops species introduced from Iraq. The diploid species were Ae. speltoides, Ae. ligustica and Ae. umbellulata and the tetraploids were Ae. triaristata, Ae. kotschyi, Ae. crassa, Ae. lorentii and Ae. triuncialis. Crosses were made by using the tetraploids as female and the diploids as male. Six amphiploids which were relatively fertile were obtained by treating F1 seedlings with colchicine and the amphiploid grains were obtained from the self pollinated spikes. They were from Ae. kotschyi×Ae. speltoides, Ae. kotschyi×Ae. ligustica, Ae. triaristata×Ae. umbellulata, Ae. kotschyi×Ae. umbellulata, Ae. lorentii×Ae. umbellulata and Ae. triuncialis×Ae. umbellulata. The morphology, fertility and meiotic chromosome pairing in these amphiploids were studied. Meiotic chromosome behaviours in the diploid and tetraploid parents were studied. The amphiploids obtained in the present investigations may be used as a material for the transfer of useful economic traits to the allohexaploid wheat Triticum aestivum.
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  • II. Influence of Ammi majus and Ammi visnaga extracts on meiosis of Vicia faba
    A. S. Shehab, Z. M. Adam, Th. Rashad
    1984 Volume 49 Issue 1 Pages 21-26
    Published: March 25, 1984
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The effect of water extract of two medicinal plants, Ammi majus and Ammi visnaga on meiosis, pollen length and pollen viability were studied. Most of the treatments gave high percentage of abnormalities. The percentage of anomalies in the 1st division was higher than those in the 2nd division. The induced irregularities were: Stickiness, bridges, spindle disturbance, lagging chromosome, breaks and fragments and multinucleate cell.
    The two plants extracts caused a decrease in the pollen grain length and gave mild increase in the pollen viability.
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  • M. C. Therrien, W. F. Grant
    1984 Volume 49 Issue 1 Pages 27-32
    Published: March 25, 1984
    Released: March 19, 2009
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    Seeds of Lotus corniculatus L., cv. ‘Mirabel’, were treated with 0.001, 0.01, 0.1 and 1.0% ethyl methanesulfonate (EMS). Selfed, selectively crossed, and openpollinated lines were assessed for meiotic chromosome aberrations and quadrivalent formation in plants derived from treatment over four generations. Effects of EMS were confined largely to the M1 generation with some persisting to the M3 and M4 generations after outcrossing. Significant increases in chromosome aberrations were not recovered in the progeny except for a single dose in the M3 generation after open-pollination. The frequency of quadrivalent formation in the control population was less than previously reported for this species suggesting some selection for increased diploidization had occurred. Meiotic chromosome pairing would appear to be under multigenic control as the frequency of quadrivalent formation increased with EMS treatment but not to the extent expected if controlled by a major gene (s). Further studies are required to establish more precisely the genetic control of meiotic pairing in this species.
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  • G. R. Rao, Anil Kumar
    1984 Volume 49 Issue 1 Pages 33-38
    Published: March 25, 1984
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    Morphology and meiosis of S. retroflexum (2n=48) and S. nodiflorum ssp. nutans (2n=24), and of their hybrids (F1, 2n=36) and synthetic polyploids (C2, 2n=72) were studied in detail. The hybrids showed irregular meiosis, they were sterile and did not set fruit. The synthetic polyploids showed mostly normal meiosis, the pollen fertility was much increased. They set fruit and seed spontaneously. From these studies, it is suspected that polyploidy and structural differences of chromosomes are the main factors in genetic isolation of the species.
    On the basis of chromosome behaviour of the parents S. retroflexum, S. nodiflorum ssp. nutans, hybrids and synthetic polyploids, at meiosis, their genomic constitution is represented as AABB, A'A', AA'B and AAA'A'BB, respectively.
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  • J. L. Karihaloo, A. K. Koul
    1984 Volume 49 Issue 1 Pages 39-47
    Published: March 25, 1984
    Released: March 19, 2009
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    Genus Ixiolirion is represented in Kashmir by a single species, I. tataricum. Plants collected from Pampore are hexaploid with 72 chromosomes. Karyology and mode of chromosome synapsis during male meiosis indicate that the population is a segmental alloploid. Comparison of karyotypes reveals that the chromosomes of Ixiolirion hardly bear any structural homology with members of either Alstroemerieae or Agaveae. Presence of leafy scape and subumbellate inflorescence alongwith cytological features like very small chromosomes and symmetric karyotype give Ixiolirion a unique and primitive position in Amaryllidaceae (sensu Hutchinson) and justify its treatment into a distinct tribe Ixiolirieae or subfamily Ixiolirioideae. Similarity between Ixiolirion and Hemerocallideae in both plant morphology and chromosome complement supports their placement close to one another. Polyploidy and segregational irregularities during meiosis explain the existence of morphological diversity and consequent taxonomic confusion in the genus.
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  • V. S. Manickam
    1984 Volume 49 Issue 1 Pages 49-59
    Published: March 25, 1984
    Released: March 19, 2009
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    1. Chromosome numbers for thirty species of ferns indigenous to the Palnis have been reported in the present study. All these numbers except those of Botrychium lanuginosum and Sphaerostephanos unitus are first reports from the Palnis.
    2. The following species are studied cytologically for the first time from S. India: Botrychium daucifolium, Macrothelypteris ornata, Christella papilio, Polystichum setiferum, Hypodematium crenatum.
    3. Chromosome numbers for the following species have been reported for the first time: Adiantum zollingeri, Microlepia majuscula, Thelypteris confluens, Diplazium sp. (a), D. travancoricum.
    4. The present study taken together with the previous reports reveals the existence of new cytotypes in the following species: Adiantum raddianum. Macrothelypteris ornata, Christella dentata, Cyclosorus interruptus, Diplazium esculentum, Polystichum setiferum, Hypodematium crenatum.
    5. Out of fifty three species of ferns known cytologically from the Palnis thirty are polyploids (60 per cent).
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  • II. Propham, chlorpropham, and 2, 4-dinitrophenol
    Thomas L. Rost, Steven L. Morrison
    1984 Volume 49 Issue 1 Pages 61-72
    Published: March 25, 1984
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The effects of three chemicals, propham (Isopropyl carbanilate), chlorpropham (Isopropyl m-chloro-carbanilate), and DNP (2, 4-dinitrophenol) on oxygen uptake, ATP synthesis, cell division and cell cycle distribution in root tips of pea (Pisum sativum L.) ‘Alaska’ are reported. At the lowest concentration tested for each chemical (chlorpropham, 4.1×10-7 M; DNP, 1×10-6 M; and propham, 1.2×10-6 M) a reduction in the number of cells able to enter into mitosis was observed. DNP and propham induced a small number of abnormal mitoses, but chlorpropham caused a significant percentage of aberrancies (50%). At the higher range of concentrations tested, chlorpropham (4.1×10-4M) induced a similar mitotic inhibition response, but DNP and propham showed differences. Propham (1.2×10-3 M) caused a rapid decrease in number of mitoses so that by 6 hrs less than 1% of the total cells were dividing and all of them were abnormal, by 24 hrs this level was reduced to about 0.2%. DNP (1×10-3 M) caused an initial reduction in the number of mitotic figures followed by severe inhibition of entry into mitosis; division figures were abnormal from 3 hrs onward. DNP at 1×10-3 M caused the complete inhibition of oxygen uptake and ATP synthesis and inhibited mitotic entry and exit after 3 hrs. This study shows that although DNP (an uncoupler of respiration) and propham (a protein synthesis inhibitor) have different modes of action, both have severe and rapid mitotic inhibitory effects. It also reiterates with mitotic kinetic evidence that chlorpropham is a direct mitotic poison.
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  • O. P. Sharma, N. K. Tripathi
    1984 Volume 49 Issue 1 Pages 73-79
    Published: March 25, 1984
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The chromosomes of two Nandid fishes, viz., Nandus nandus and Badis badis from India have been studied. N. nandus has a diploid count of 48 chromosomes with NF=84, while B. badis possesses 2n=46 with NF=52. The haploid chromosome formula worked out for N. nandus is n=2m+9sm+7st+6t, while for B. bodis, it is n=3m+20t. Certain mitotic and meiotic polyploid cells from testicular material have been recorded in both the species. The sex chromosomes could not be distinguished in either of the species. The cytotaxonomical relationship between family Nandidae and suborder Anabantoidei (order: Perciformes) has been discussed.
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  • S. O. Oyewole
    1984 Volume 49 Issue 1 Pages 81-86
    Published: March 25, 1984
    Released: March 19, 2009
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    The pachytene chromosomes of the microsporocytes were analysed in defining the karyotype of D. barteri because an analysis of the somatic complement has been previously found to be inadequate to give the correct karyotype of the species. The analyses of the pachytene chromosomes revealed structural and morphological hybridity among the chromosomes by which not only the karyotype was resolved but also the probable mode of origin of the complement was defined, as well as a new basic chromosome number, x=6 (instead of x=8), determined for the genus.
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  • S. O. Oyewole
    1984 Volume 49 Issue 1 Pages 87-93
    Published: March 25, 1984
    Released: March 19, 2009
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    Meiotic behaviour in the microporocytes (pmc) and the subsequent behaviour of the meiotic products were investigated in plants collected from two population sites of the species distribution in Nigeria. All stages from leptonema to pollen development were encountered in the same anthers. Though the percentage of normal meiotic pairing as well as pollen stainability is high, the percentage of pollen germinability is very low; pollen tube growth in vitro is extremely slow and, in vivo, pollen tubes fail to elongate and penetrate the stylar tissue. Pollen protoplast dies and disintegrates rather quickly after anther dehiscence.
    Chromosome morphology and behaviour helped to explain the nature of the chromosome composition of this taxon, and a new basic chromosome number is suggested for the genus. Sexual sterility is explained to be caused by genetic instability and defficiency in the genotype constitution of the spores as a result of the hybrid origin of the taxon.
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  • C. Balog
    1984 Volume 49 Issue 1 Pages 95-103
    Published: March 25, 1984
    Released: March 19, 2009
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  • S. Mazrooei, A. Kabarity
    1984 Volume 49 Issue 1 Pages 105-116
    Published: March 25, 1984
    Released: March 19, 2009
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    Parahypon, cafergot and spasmocibalgin inhibited the nucleic acid synthesis and cell division in various concentrations used. This inhibitory effect was so total in the case of cafergot and spasmocibalgin that it was impossible to carry out any fur-ther cytological studies. Parahypon in diluted concentrations has a stathmokinetic effect. This led to the conclusion that parahypon, cafergot and spasmocibalgin have a major harmful effect upon the process of cell division in the meristematic cells of Allium cepa root tips.
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  • M. Sanjappa, R. P. Bhatt
    1984 Volume 49 Issue 1 Pages 117-125
    Published: March 25, 1984
    Released: March 19, 2009
    JOURNAL FREE ACCESS
    The present communication deals with the chromosome number and karyotype analysis of seven species of the genus Indigofera. The karyotype study is made for the first time in the species investigated here. Among the seven species studied, four are diploids with 2n=16 (I. vicioides, I. arrecta, I. duthiei and I. spicata), one is a tetraploid with 2n=32 (I. angulosa) and two are hexaploids with 2n=48 (I. heterantha and I. amblyantha). The basic chromosome number x=8 for the genus is supported by this work. Karyotype analysis revealed that I. duthiei is primitive and I. amblyantha the advanced, the five other species are being intermediate be-tween these two. The chromosomes showed only nearly median and nearly submedian centromeres. The karyotypes further, show that structural changes and to a certain extent polyploidy might have played an important role in speciation and evolution of the genus.
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  • IV. Electron microscopic autoradiography of [3H]-proline incorporation
    Rüdiger Riehl
    1984 Volume 49 Issue 1 Pages 127-142
    Published: March 25, 1984
    Released: March 19, 2009
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    Formation of the egg-membrane and the attaching-filaments of the marine goby Pomatoschistus minutus was studied with electron microscopic autoradiography using the tracer L-[3H]-proline. The egg-membrane is formed in the chronological sequence as follows: first labeled material is found in the oocytoplasm by 15 min post-injection, in Golgi bodies by 30-60 min, in dense-cored vesicles and pinocytotic vesicles by 3h and the substance of the egg-membrane by 12-24h post-injection. This suggests that the material forming the egg-membrane is synthesized in the oocytoplasm, concentrated in the Golgi bodies and then transfered via densecored and pinocytotic vesicles to the developing egg-membrane. In the follicle epithelium first label appears in stage II and III oocytes at 30 min post-injection and reaches the maximum concentration in the endoplasmic reticulum by 24h. These findings suggest that the egg-membrane of Pomatoschistus minutus is produced by the oocyte itself, whereas the attaching-filaments are synthesized by the endoplasmic reticulum of the follicle cells. Therefore according to the classical definition of Waldeyer (1906) the egg-membrane of this species is a primary envelope, while the attaching-filaments represent a secondary envelope or chorion.
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  • Marie-France Turchini, Jean-Pascal Turchini, Aimé Geneix, Paul ...
    1984 Volume 49 Issue 1 Pages 143-149
    Published: March 25, 1984
    Released: March 19, 2009
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    Action of the Cis Diamino Dichloro-Platinum on the Ultrastructural
    Aspect of Human Metaphasic Lymphocytes Chromosomes
    The action of C D D P has been tested in vitro on human lymphocytes cultures.
    The doses were near these used in therapeutic.
    Various aberrations were observed on chromosomes.
    The optic microscopy shows: gaps, chromatid's breaks, “minute” chromosomes, and numerous others exchanges. The same aberrations were seen in electronic microscopy with further an aspect of “stickiness” and micronucleation.
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  • J. S. Sindhu, A. E. Slinkard, G. J. Scoles
    1984 Volume 49 Issue 1 Pages 151-155
    Published: March 25, 1984
    Released: March 19, 2009
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    Karyotype analysis was performed in 11 lines of Lens orientalis. There were no differences in chromosome morphology of different accessions. The diploid chromosome number was 14 and the average chromosome length was 4.34μ. The karyotype comprised one metacentric, three submetacentric and three acrocentric chromosome pairs. The fourth longest chromosome pair (a submetacentric) was characterized by a conspicuous secondary constriction. A karyogram and an idiogram were prepared and the karyotypic formula developed.
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  • Mitotic Complements in 19 Species
    R. C. Verma, K. Kesavacharyulu, S. N. Raina
    1984 Volume 49 Issue 1 Pages 157-169
    Published: March 25, 1984
    Released: March 19, 2009
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    Detailed karyotypes were studeid in 19 species of Crotalaria, of which seven have not been investigated so far. Fifteen species were diploids (2n=16) and four were tetraploids (2n=32). Karyomorphology was alsmost uniform in various species. The basic karyotype consisted of eight chromosomes containging three long and five medium chromosomes. Various species differed in the number of V, L, and J chromosomes. Nucleolar chromosomes in the form of secondary constriction in longest pair were observed in eight species. Three broad categories of nu-cleolar chromosomes were recognised. Three species had only one nucleolar chromo-some. There was an overall stability of chromosome morphology and symmetry, therefore species differentiation can not be correlated with chromosomal differentiation. Polyploidy is rare and has not played any significant role in the speciation of the genus. It has been concluded that true basic number is eight.
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  • R. K. Somashekar, M. T. G. Gowda, P. Venkatasubbaiah
    1984 Volume 49 Issue 1 Pages 171-175
    Published: March 25, 1984
    Released: March 19, 2009
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    The present work confirms the antimitotic, cytotoxic and clastogenic effects of the fungicide Topsin in case of Allium cepa. It also induced C-metaphase, spin dle abnormalities and inhibited cytokinesis. Topsin is being used as a protectant and eradicant in controlling fungal diseaese of various crop plants. Therefore it is suggested that the mutagenic potential of Topsin on such crop plants should be tested before it is recommended for wide use in the agricultural field. The infor-mation on crop plants will be helpful not only from the view point of understanding the mechanism of cytological damage but also for its implication on environmental pollution.
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  • R. K. Somashekar, M. T. G. Gowda
    1984 Volume 49 Issue 1 Pages 177-181
    Published: March 25, 1984
    Released: March 19, 2009
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    Vitavax, a systemic fungicide was tested for its antimitotic and clastogenic effects on Allium cepa. The results obtained showed that Vitavax induces various types of spindle abnormalities, inhibits cell plate formation and exhibits antimitotic activity. Clastogenic effects of the fungicide were pronounced at a concentration of 500mg/l and above.
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  • IV. Comparative study of natural and induced polyploids
    A. K. Singh, K. S. Yadav
    1984 Volume 49 Issue 1 Pages 183-192
    Published: March 25, 1984
    Released: March 19, 2009
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    Colchiploids were raised in C. melo var. momordica and C. prophetaranm. Morphologically autotetraploids were vigorous with a little increase in fruit size, though with decrease in number of fruits per vine and seeds per fruit.
    A comparative meiotic analysis of colchiploids and four natural polyploids, C. pustulatus, C. membranifolius, C. meeusei and C. heptadactylis revealed that C. pustulatus and C. membranifolius with regular bivalent assoication are allopolyploids, while C. meeusei and C. heptadactylis with a few multivalent assoications are autopolyploids, may be segmental allopolyploids. A higher frequency of biva-lents in C. heptadactylis compared to earlier reports suggests that either selection of mutants ensuring bivalent association or diplontic gametes are evolving these species to diplontic behaviour. A high bivalent frequency comparative to natural polyploids observed in colchiploids suggest that they can attain diplontic behaviour like natural polyploids with generation advance and later may stabilise cytologically, sexually and agronomically.
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  • B. K. Biswas, A. K. Sharma
    1984 Volume 49 Issue 1 Pages 193-200
    Published: March 25, 1984
    Released: March 19, 2009
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    Chromosome study has been carried out on ten species belonging to three genera of the family Magnoliaceae, with the application of improved techniques. Only two species, namely Magnolia liliflora (2n=76) and M. grandiflora (2n=114) show high chromosome numbers, the rest showing 2n=38 chromosomes. The general features include uniformity of chromosome number, graded karyotypes, with mostly metacentric chromosomes and the size ranging from medium to small. The plants, with high chromosome number in the polyploid species, have long chromosomes and show no reduction in chromosome size. The species differ from one another in the type and number of chromosomes with secondary constrictions. Minor structural alterations of chromosomes have probably played the most important role in the evolution of genus and species rather than polyploidy and aneuploidy.
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  • Joventino D. Soriano
    1984 Volume 49 Issue 1 Pages 201-207
    Published: March 25, 1984
    Released: March 19, 2009
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  • H. N. B. Gopalan, G. D. E. Njagi
    1984 Volume 49 Issue 1 Pages 209-214
    Published: March 25, 1984
    Released: March 19, 2009
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    The antimicrobial food additive AF-2 is mutagenic in bacteria, Neurospora, yeast and Drosophila. AF-2 breaks mammalian chromsomes. We studied by Feulgen staining the types and distribution of chromosome aberrations induced by AF-2 in Vicia faba root meristems. AF-2 induces (a) mitostasis resulting in accumulation of cells in G1, S or G2 phase, (b) chromosome condensation, (c) pycnosis of the interphase nuclei and (d) anaphase bridges and micronuclei. The bridges involve all the six chromosome pairs but largely the SAT-chromosomes. Attachments are confined to secondary constrictions and chromosome tips. These effects are likely to be due to an indirect action of AF-2 on the genetic material.
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  • I. Some aspects of carotenogenesis
    M. Fátima Santos, J. F. Mesquita
    1984 Volume 49 Issue 1 Pages 215-228
    Published: March 25, 1984
    Released: March 19, 2009
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    The process of accumulation of secondary carotenoids (astaxanthin) in Haematococcus lacustris was analysed in the optical and electron microscopes. The more relevant results of this cytological study are the following: a. In motile cells, the lipochromes are spherical inclusions, initially of small size, and located in the perinuclear cytoplasm apparently in preferential correlation with E. R. Although without a true limiting biomembrane, these sudanophilic and osmiophilic inclusions do not easily fuse when contacting. b. In the cysts, the pigment deposits, although being identical to the ones of the motile cells in what concerns their location and affinity for lipids “stains”, show a variety of shapes, including “long filaments”, rods and more or less complex reticulate forms. c. Cells of the older cultures (11-20 days) appear almost uniformly “stained” deep red. This process is reversible, i.e., these cultures again turn green when successively subcultured to fresh media. d. Apart from the stigma globules, the haematochrome is always localized outside the chloroplast, the photosynthetic apparatus of which remains practically intact through this process. Then, no sign of plastidal transformation, (chloroplast in chromoplast) comparable to the changes which take place in various organs of higher plants was observed.
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  • Mitosis and cytokinesis
    J. F. Mesquita, M. Fátima Santos
    1984 Volume 49 Issue 1 Pages 229-241
    Published: March 25, 1984
    Released: March 19, 2009
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    In this article are presented the results of the ultrastructural study of the cell division in Haematococcus lacustris. The more significative data are as follows: the nuclear envelope is maintained intact practically throughout mitosis, as it only breaks down at the end of telophase when the daughter nuclei are separated. The disappearance of the nucleolus, which in the interphase nuclei display the two typical structural components (granulous and fibrillar), is sometimes delayed, since in late metaphase-early anaphase nucleolus clearly organised were observed. The spindle microtubules (NITS) seem to have an exclusively endonuclear origin, as neither through polar fenestrae nor nuclear pores they appear to be related with any extranuclear structure. In metaphase and anaphase we can see that the above endonuclear spindle is formed by “continuous” and chromosomic MTS. The former are persistent in the interzonal region up to telophase and the latter are deep in the chromatin, sometimes in apparently differentiated chromosomic regions (centromeres). In late anaphase-early telophase, the nucleus is seen more elongated, sometimes curved and repeatedly with dilated ends (dumbell shaped). The nuclear envelope of the telophasic nucleus breaks down in the middle-region and surrounds the two chromosomic groups (daughter nuclei). Between them, a growing cleavage furrow (invagination of the plasmalemma) ends by leading to the division of the protoplast (cytokinesis). This cleavage furrow is always associated to a microtubular system (phycoplast) similar to that which has been described in other algae.
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  • Connie S. Karagiannis, A. J. Pappelis, V. M. Russo
    1984 Volume 49 Issue 1 Pages 243-250
    Published: March 25, 1984
    Released: March 19, 2009
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    When onion bulb epidermal cells are activated by exposure of turgid leaf bases to ambient atmosphere, nucleoli in cells adjacent to wound sites enlarge within three hours and change their shapes from round to oval and elongated-oval, and finally form dumbbell-shaped nucleoli. Nucleolar vacuoles were observed in 10% of the elongated-oval and dumbbell type nucleoli three hours after wounding and exposure to ambient atmosphere and in 70% of these 24 hours after treatment. These changes are inferred to be the result of activity at the molecular level (RNA transcriptional and ribosomal subunit processing).
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  • Masanobu Kitami
    1984 Volume 49 Issue 1 Pages 251-256
    Published: March 25, 1984
    Released: March 19, 2009
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  • Masanobu Kitami
    1984 Volume 49 Issue 1 Pages 257-264
    Published: March 25, 1984
    Released: March 19, 2009
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    A certain chemo-attractant which controls the cell movement is present in the culminating fruiting body as it is in the aggregation center. Cells at the culmination stage, too, are chemotactically sensitive to c-AMP. The motility of the fruiting body cells depends upon the changes in c-AMP concentration; moreover, it tends to be high in lower c-AMP concentrations as compared with that of the pseudoplasmodium cells. This suggests that the cell movement may be basically controlled by c-AMP in the culminating fruiting body as well as in the aggregating cell streams and the migrating pseudoplasmodium.
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