Ultrastructural investigations of mature embryo sacs of Daaucus carota, D. aureus and D. muricatus ? possible cytological explanations of paternal plastid inheritance

1991 ◽  
Vol 4 (4) ◽  
Author(s):  
G. Hause
Keyword(s):  
Mature Embryo ◽  
Plastid Inheritance

Reproductive development in two species of Darwinia Rudge (Myrtaceae)

1969 ◽  
Vol 17 (2) ◽  
pp. 215 ◽  
Author(s):  
N Prakash
Keyword(s):  
Embryo Sac ◽  
Pollen Grains ◽  
Reproductive Development ◽  
Outer Zone ◽  
Mature Embryo ◽  
Globular Embryo ◽  
Primary Endosperm Nucleus ◽  
Oil Glands ◽  
Polygonum Type ◽  
History Of

In Darwinia the floral parts are differentiated in a "calyx-orolla-gynoeciumandroecium" sequence. In individual buds stages of microsporogenesis markedly precede corresponding stages of megasporogenesis. The anther is tetrasporangiate with all sporangia lying in one plane. The secretory tapetum is one- to three-layered within the same microsporangium and a large number of Ubisch bodies are formed. The anthers dehisce by minute lateral pores and an ingenious mechanism helps disperse the twocelled pollen grains. A basal placenta in the single loculus of the ovary bears four ovules in D. micropetala and two in D. fascicularis. In both species, however, only one ovule is functional after fertilization. The fully grown ovules are anatropous, crassinucellar, and bitegmic; the inner integument forms the micropyle. The parietal tissue is most massive at the completion of megasporogenesis but is progressively destroyed later. The embryo sac follows the Polygonum type of developnlent and when mature is five-nucleate, the three antipodals being ephemeral. Following fertilization, the primary endosperm nucleus divides before the zygote. Subsequent nuclear divisions in the endosperm mother cell are synchronous and lead to a free-nuclear endosperm which becomes secondarily cellular, starting from the micropylar end at the time the globular embryo assumes an elongated shape. Embryogeny is irregular and the mature embryo is straight with a massive radicle and a hypocotyl which terminates in two barely recognizable cotyledons. Sometimes the minute cotyledons are borne on a narrow neck-like extension of the hypocotyl. A suspensor is absent. Both integuments are represented in the seed coat and only the outer layer of the outer and the inner layer of the inner integuments, with their thick-walled tanniniferous cells, remain in the fully grown seed. The ovary wall is demarcated into an outer zone containing oil glands surrounded by cells containing a tannin-like substance and an inner zone of spongy parenchyma. In the fruit this spongy zone breaks down completely but the outer zone is retained. The two species of Darwinia, while closely resembling each other in their embryology, differ significantly from other Myrtaceae. However, no taxonomic conclusions are drawn at this stage, pending enquiry into the life history of other members of the tribe Chamaelaucieae.

EFFECT OF 2,4-D AND NAA ON SOMATIC EMBRYOGENESIS FROM APICAL PORTION OF GROUNDNUT (ARACHIS HYPOGAEA L.)

2021 ◽  
Vol 1 (7) ◽  
pp. 119-124
Author(s):  
Muniappan V ◽  
Manivel P ◽  
Prabakaran V ◽  
Palanivel S ◽  
Parvathi S
Keyword(s):  
Somatic Embryogenesis ◽  
Somatic Embryo ◽  
Arachis Hypogaea ◽  
Somatic Embryos ◽  
Mature Embryo ◽  
Induction Medium ◽  
Embryogenic Cultures ◽  
Apical Portion ◽  
Arachis Hypogaea L ◽  
Somatic Embryo Induction

Somatic embryogenesis was carried out epicotyl portion of the mature embryo/apical portion. The somatic embryo induction medium containing 2,4-D or NAA (10.0 to 50.0 mg/l). Of the two concentrations tested 2,4-D (30.0mg/l) recorded the highest percentage of response followed by NAA (30.0mg/l). But the highest number of somatic embryo were recorded in 30.0mg/l of 2,4-D followed by NAA. The apical portion of the mature embryo formed direct embryos without any intervention of callus. The maximum percentage of embryogenic cultures were noticed in 30.0mg/l of 2,4-D followed by NAA at 30.0mg/l. for the differentiation of somatic embryos, the embryogenic masses were transferred to medium without any growth regulator. The maximum number of somatic embryos per culture was recorded in 30 mg/l of 2,4-D followed by 30.0 mg/l of NAA. Keywords: Arachis hypogaea L.,Somatic Embryogenesis, 2,4-D and NAA

scholarly journals Differential Expression Pattern of Goat Uterine Fluids Extracellular Vesicles miRNAs during Peri-Implantation

Cells ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2308
Author(s):  
Yanshe Xie ◽  
Guangbin Liu ◽  
Xupeng Zang ◽  
Qun Hu ◽  
Chen Zhou ◽  
...  
Keyword(s):  
Extracellular Vesicles ◽  
Small Rnas ◽  
Target Genes ◽  
Embryo Implantation ◽  
Mature Embryo ◽  
Luciferase Reporter ◽  
Small Rna Sequencing ◽  
Transmission Electron ◽  
Differential Expression Pattern ◽  
Endometrial Epithelium

Early pregnancy failure occurs when a mature embryo attaches to an unreceptive endometrium. During the formation of a receptive endometrium, extracellular vesicles (EVs) of the uterine fluids (UFs) deliver regulatory molecules such as small RNAs to mediate intrauterine communication between the embryo and the endometrium. However, profiling of small RNAs in goat UFs’ EVs during pregnancy recognition (day 16) has not been carried out. In this study, EVs were isolated from UFs on day 16 of the estrous cycle or gestation. They were isolated by Optiprep™ Density G radient (ODG) and verified by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and Western blotting. Immunostaining demonstrated that CD63 was present both in the endometrial epithelium and glandular epithelium, and stain intensity was greater in the pregnant endometrium compared to the non-pregnant endometrium. Small RNA sequencing revealed that UFs’ EVs contained numerous sRNA families and a total of 106 differentially expressed miRNAs (DEMs). Additionally, 1867 target genes of the DEMs were obtained, and miRNA–mRNA interaction networks were constructed. GO and KEGG analysis showed that miRNAs were significantly associated with the formation of a receptive endometrium and embryo implantation. In addition, the fluorescence in situ hybridization assay (FISH) showed that chi-miR-451-5p was mainly expressed in stromal cells of the endometrium and a higher level was detected in the endometrial luminal epithelium in pregnant states. Moreover, the dual-luciferase reporter assay showed that chi-miR-451-5p directly binds to PSMB8 and may play an important role in the formation of a receptive endometrium and embryo implantation. In conclusion, these results reveal that UFs’ EVs contain various small RNAs that may be vital in the formation of a receptive endometrium and embryo implantation.

scholarly journals Anatomía de la semilla de Casimiroa edulis (Rutaceae), "zapote blanco", durante su desarrollo

2017 ◽  
pp. 67
Author(s):  
Hilda Araceli Zavaleta-Mancera
Keyword(s):  
Seed Development ◽  
Mature Embryo ◽  
Mature Seed ◽  
Protein Bodies ◽  
Fast Green ◽  
Oil Glands ◽  
Specific Staining ◽  
Starch Grains ◽  
Casimiroa Edulis ◽  
Mexican Species

The seed of the Mexican species, Casimiroa edulis Llave et Lexarza is valued for medicinal purposes. We have studied its anatomy in different stages of development from ovule to mature seed. We applied general staining with safranin and fast green and specific staining for the detection of starch, lipids, lignin, polyphenols, and proteins. Embryo and seed development was also evaluated on the basis of volume. The ovule is sessile, bitegmic, crassinucellate, hemianatropous, with a nucellar curvature of 30-40º and a large hilum. The seed develops a large pachychalaza that covers approximately 70% of the surface. The testa is thin, nonlignified and tanniferous. The mature embryo occupies about 90% of the whole volume of the seed and contains lysigenous oil glands, starch grains and protein bodies. The radicle is not directed exactly at the micropyle. lt is located in the dorsal micropylar third of the seed. Casimiroa edulis had been described as lacking endosperm, but in reality the mature seed has a small amount of endosperm under the pachychalaza.

INHERITANCE OF VARIEGATION IN BARLEY

1946 ◽  
Vol 24c (5) ◽  
pp. 145-157 ◽  
Author(s):  
T. J. Arnason ◽  
J. B. Harrington ◽  
H. A. Friesen
Keyword(s):  
Genetic Factor ◽  
Reciprocal Cross ◽  
Gene Content ◽  
High Rate ◽  
Plastid Inheritance

A strain of variegated barley that originated in a Saskatchewan field produces, on selfing, progeny of which approximately 90% are albino, the remainder striped or variegated with rare full green exceptions. In crosses, variegated ♂ × green ♀ produced 7 albino, 4 striped, and 11 green F1 plants. The reciprocal cross yielded 1 striped and 41 green F1 plants. F2 segregation approximated three green to one of all others (albino and variegated). From some F2 and F3 progenies it was inferred that two genetic factor pairs might be segregating. On that hypothesis the dominant hypostatic factor for variegation must be very unstable, mutating at a high rate to white. The peculiarities of inheritance may be explained also, however, on the basis of a combination of gene and (maternal) plastid inheritance. On this interpretation the plastids present in the egg affect the colour of the seedling that develops from it. When green plastids or proplastids are present in the egg, many of them, but not necessarily all, are induced to mutate if the white w gene is homozygous, but fewer if the w gene is heterozygous. If white plastids only are present in the egg it is probable that the seedling will be an albino regardless of gene content.

Strcture of the Mature Embryo of Theobroma cacao L.

1972 ◽  
Vol 36 (5) ◽  
pp. 939-945 ◽  
Author(s):  
E. J. DUNCAN ◽  
A. W. TODD
Keyword(s):  
Theobroma Cacao ◽  
Mature Embryo ◽  
Theobroma Cacao L

The development of fused− embryos of Drosophila melanogaster

Development ◽  
1985 ◽  
Vol 87 (1) ◽  
pp. 99-114
Author(s):  
Alfonso Martinez-Arias
Keyword(s):  
Cell Death ◽  
Drosophila Melanogaster ◽  
Embryonic Development ◽  
Mature Embryo ◽  
Lethal Mutations ◽  
Extensive Cell Death ◽  
Extensive Cell ◽  
Secondary Consequence

The mutant fused (1–59·5) belongs to a class of lethal mutations in Drosophila melanogaster that produce pattern duplications in every segment of the mature embryo. A study of the embryonic development of fused'− embryos derived horn fused− mothers shows that extensive cell death occurs early in development. This cell death accounts for the smaller size of the segments in fused− embryos. The pattern duplication observed is, probably, a secondary consequence of the pattern deletion.

scholarly journals Operation procedure of sacrococcygeal fetus in fetu

2011 ◽  
Vol 51 (1) ◽  
pp. 58 ◽  
Author(s):  
Rochadi Rochadi
Keyword(s):  
Adrenal Gland ◽  
Abdominal Mass ◽  
Rare Condition ◽  
Mature Embryo ◽  
First Year ◽  
Fetus In Fetu ◽  
Sacrococcygeal Region ◽  
Parasitic Twin ◽  
Operation Procedure ◽  
First Year Of Life

Fetus in fetu is a condition in wich a fetiform calcified mass often presents in the abdomen of its host, a newborn. It is extremely rare condition, estimated once in 500,000 deliveries and has a 2: 1 male predominantly; with most patient presenting with an abdominal  mass in the first year of life. 5,13 The term fetus in fetu is used to point out an unequal division of totipotential cells of blastocyst where the result is the inclusion of a small cellular mass in the more mature embryo. It was encapsulated, pedunculated and represents a malformed monozygotic, monochorionic, diamniotic parasitic twin. In 80% cases, fetus in fetu is located  retroperitonealy but can be found in unusual location such as in oropharynx, neck, skull mediastinum, pelvis, iliac mesentery, adrenal gland, sacrococcygeal region and scrotal sac.

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