Gametogenesis in chick free download as powerpoint presentation. Segmentations of scala tympani, scala vestibuli, malleus, incus, stapes, facial nerve, chorda tympani, tympanic membrane, external auditory canal, sigmoid sinus and dura, carotid artery and bone are provided at a 125. Direct control of germline stem cell division and cyst. Save powerpoint presentations as pdf files office support. Molecular characterization of vitellogenin and vitellogenin. No other single volume includes both basic information on vectors, as well as chapters on cuttingedge topics, authored by the leading experts in the field. Author summary vitellogenesis, a hormonallyregulated process for the synthesis of yolk proteins by the fat body or liver and their sequestration in developing oocytes, takes place in all oviparous animals except mammals.
Vg first appears in the hemolymph shortly after the larva spins its cocoon. Pdf converter is a online webbased document to pdf converter software. At present, this specific antigen is known as vitellogenin, the major precursor of egg yolk protein that is synthesized in the female liver and is secreted into the blood to be incorporated into the egg. This is due in great part to a lack of information concerning the biochemical nature of the vitellogenin molecule, the hemolymph precursor of yolk protein, vitellin, as well as the functional expression of the vitellogeninencoding gene. Oogenesis,vitellogenesis and cocoon secretion in two. In addition to vitellogenesis, the oocyte receives substantial amounts of macromolecules and orga nelles from the nurse cells via the ring canals. Comparison of changes along the bpgaxis that occur during silvering betweenthe europeaneela. Molecular characterization of a cdna encoding vitellogenin.
Simak dan download berikut ini referensi pembelajaran dengan menggunakan media powerpoint untuk mata pelajaran ips smp lengkap untuk kelas 7, 8, dan 9. Namun pada kenyataannya banyak dijumpai bahwa pakan komersial yang diformulasikan khusus untuk induk udang masih nampak defisiensi asam arachidonat dan epa. J p sumpter and s jobling department of biology and biochemistry. Vitellogenesis starts in the relatively late stages of oogenesis, toward the end of which the size of the. There are many common points during the vitellogenesis of worms, insects and vertebrates amphibians. Vitellogenesis is the process of yolk formation via nutrients being deposited in the oocyte. All contain reserve material of various kinds such as yolk, glycogen, nucleic acids dna, rna, etc. Vitellogenin vtg or less popularly known as vg from latin vitellus, yolk, and genero, i produce is a precursor protein of egg yolk normally in the blood or hemolymph only of females that is used as a biomarker in vertebrates of exposure to environmental estrogens which stimulate elevated levels in males as well as females. Zoological science this study reports a viable means of identifying the vitellogenic cycle and limited estrus period in hawksbill turtles for the purposes of developing captive breeding program, based on the combination of blood metabolite parameters triglyceride, total protein, and calcium levels, feeding status, and ovary condition.
Stem cells reside in specialized niches that provide signals required for their maintenance and division. Various investigations are also in favor ofthe existence ofastimulating neurohormonal control of vitellogenesis. Vitellogenesis during the ovarian development in freshwater. The control of vitellogenesis in the mosquito, aedes aegypti the.
Ethanol is produced in india for blending with petrol. Vitellogenesis, oocyte maturation pattern, spawning rhythm and spawning frequency in otolithes ruber schneider, 1801 sciaenidae in the kuwaiti waters of the arabian gulf stephen dadzie department of biological sciences, kuwait university, p. Therefore the name vitellogenesis inhibiting hormone vih was introduced by charniauxcotton around theeighties. Oogenesis, vitellogenesis and cocoon secretion in two freshwater leeches from assiut, egypt hanaa a. The immersion protocol was validated using the highly potent estrogenic agent des at a concentration of 1 ppm and an exposure period of 11 d. The yolk deposited in the oocytes of reptiles and birds is required for the development and growth of embryo. The first edition of biology of disease vectors was a landmark text, and this edition promises to have even more impact as a reference for current thought and techniques in vector biology.
Oogenesisthe differentiation of the ovumdiffers from spermatogenesis in several ways. Polyploidy has also been implicated in hormoneregulated development and reproduction. Vitellogenin is the generic name for a unique group of proteins that are synthesized extraovarially and become the major egg yolk protein. Vitellogenin is an egg yolk precursor protein expressed in the females of nearly all oviparous species including fish, amphibians, reptiles, birds, most invertebrates, and monotremes. Vitellogenesis definition of vitellogenesis by merriamwebster. However, when eels were subsequently stimulated by 3 weekly carp pituitary extract injections, the expression of the same genes and plasma. Impact of edcs on trout in an effluent dominated stream. Vitellogenic definition of vitellogenic by the free dictionary. End of vitellogenesis gth ii produced in higher levels than gth i follicle produces maturation. This edition examines the control of disease vectors through topics such as general biological requirements of vectors, epidemiology, physiology and molecular biology, genetics, principles of control and. The water was changed daily and they were fed ad libitum with commercial pelletized food. Semuanya kami rangkum dalam satu judul yaitu materi powerpoint ips smp. A diagrammatic representation of the in vitro assay for vitellogenin synthesis. Received for publication, july 27, 1989 tarlochan s.
Vitellogenesis as a biomarker for estrogenic contamination of the aquatic environment. Juvenile hormone activates the transcription of cell. Pdf developing offspring of oviparous animals are entirely dependent on. Early electron microscopic investigations point to a biphasic yolk synthesis, first within the ovary, followed by heterosynthesis at extraovarian sites. Whereas the gamete formed by spermatogenesis is essentially a motile nucleus, the gamete formed by oogenesis contains all the materials needed to initiate and maintain metabolism and development. Vg synthesis rises 48 days after the larvalpupal apolysis and then declines to low levels during diapause 100, 102. Multiply to form oogonia initiating the multiplication phase. Biology of disease vectors presents a comprehensive and advanced discussion of disease vectors and what the future may hold for their control. Although juvenile hormone jh is known to regulate polyploidy in insect models and. Hagedorn department of entomology, cornell university, ithaca, new york 14853 j. Vitellogenesis definition of vitellogenesis by merriam. Broodstock and breeding dicentrarchus labrax and sparus aurata egg diameters 1mm. Follow these instructions to set the print quality of the pdf.
Kunkel department of zoology, university of massachusetts, amherst, massachusetts 01003 introduction vitellogenin is the generic name for a unique group of proteins that are. This is the third phase of vitellogenesis, during which the yolk plates push the lipoid drops toward the edge of the cell where two rings begin forming. On the basis of shell two of types a cleidoic eggs b noncleidoic egg a cleidoic egg these eggs contain a thick and hard outermost shell. This provides an example of a polytrophic ovary in which the nurse cells are derived from the same germ cell lineage as the oocyte. In this study, follicle cells, which attached to the previtellogenic and vitellogenic oocytes, were easily found. In 1960, otsu gave the first indications for the presence of such a factor in the thoracic. Vitellogenesis takes place in all oviparous vertebrates, including salmonid. Pituitary dopaminergic signaling d2br is increased,thebpgreproductiveaxisgnrhr1 and 2,fsh.
Here, we report that neuralderived drosophila insulinlike peptides dilps directly regulate germline stem cell division rate, demonstrating that signals mediating the ovarian response to. Environmental cues pictured at the top indicate from left to right water temperature, daylength, rainy weather, conspecific males andor females, and. These include ribosomes, mitochondria, and a large collec tion of regulatory and structural proteins and rnas. Vitellogenesis definition of vitellogenesis by the free. Reproduction is typically a cyclical process by which species perpetuate themselves and produce one or more individuals similar to itself by means of a new generation. In crustacea, reproductive function and mechanisms regulating vitellogenesis have not been fully elucidated.
In the powerpoint preferences dialog box, click general. Vitellogenesis takes place in all oviparous vertebrates, including salmonid fishes. Vitellogenesis as a biomarker for estrogenic contamination of. In insects, it starts when the fat body stimulates the release of juvenile hormones and produces vitellogenin protein. The upper panel shows ovaries dissected from previtellogenic newly eclosed and vitellogenic four day old drosophila melanogaster adult females.
Endocrinology and endocrine toxicology male, to respond to gradually rising estrogen levels by triggering a positive responsethe ovulatory gnrhdriven lh surge. In studies of sex discrimination in fish in the early 1900s, a specific antigen in the blood of gravid females was identified using immunological methods. Vitellogenesis is a sequential process incorporating the following events. Both species may start ovogenesis in water with a salinity lower than 35 ppt, such as in the case of estuaries and coastal lagoons, but the final steps leading to maturation exogenic vitellogenesis and meiotic divisions require full seawater 35 ppt.
Major stages of oogenesis what follows is a description of the major oogenic events using primarily examples from the fruit fly, drosophila melanogaster. Vitellogenesis is the process whereby the required yolk nutrients are deposited into growing oocytes, which eventually give rise to eggs. The primordial germ cell migrate from the endoderm. Ovaries times as a result of vitellogenesis deposit of yolk. Vitellogenesis is the process whereby the required yolk nutrients are deposited into. Vitellogenesis is the process through which food is progressively stored in the growing oocytes of oviparous animals, making up the yolk of the mature egg. Vitellogenin as a biomarker for xenobiotic estrogens in an. Titers remain high during diapause and drop only after yolk deposition begins in the pharate adult 119. Vitellogenesis as a biomarker for estrogenic contamination. The comparative approach on how and when vitellogenesis occurs in the diverse reproductive strategies displayed by aquatic and terrestrial lower vertebrates is presented in this chapter. Gouda zoology department, faculty of science, assiut university, assiut, egypt.
Environmental cues pictured at the top indicate from left to right water temperature, daylength. Model for regulation of vitellogenesis in teleost fish via the brainpituitarygonad bpg axis. There are many common points during the vitellogenesis of worms, insects and vertebrates amphibians, reptiles and birds. The synthesis of glycogen from glucose is called as glycogenesis. Ultrastructural studies on oocyte development and vitellogenesis. Therefore, in addition to forming a haploid nucleus, oogenesis also builds up a store of cytoplasmic enzymes. Vitellogenic definition of vitellogenic by the free. Vitellogenesis also known as yolk deposition is the process of yolk formation via nutrients being deposited in the oocyte, or female germ cell involved in reproduction of lecithotrophic organisms. Juvenile hormonedependent kazaltype serine protease. Vitellogenesis and choriogenesis in fishes springerlink.
Recent advances in molecular techniques have enhanced our understanding of the genetic control of yolk synthesis in. Previtellogenesis and vitellogenesis previtellogenesis further includes stages involved before formation of the yolk where as vitellogenesis refers to the stages involved in formation of yolk. Later studies postulated that such a factor may act directly on the ovary on an intermediate organ or on both. Tissueextrinsic signals can also modify stem cell activity, although this is poorly understood. Embryology lecture notes different types of eggs with examples classification of egg on the basis of the amount of yolk eggs are grouped into three types on the basis of the amount of yolk present in them. Selain materi powerpoint yang bisa didownload secara cumacuma, juga dilengkapi dengan materi yang disajikan dalam format pdf.
Vitellogenin is the precursor of the lipoproteins and phosphoproteins that make up most of the protein content of yolk. This type of egg in which the future developmental potentialities are not predetermined is known as regulative or indeterminate egg. While the presence of ribosomes is easy to demonstrate in oocytes undergoing vitellogenesis, electron microscopy shows very few typical ribosomes in very young xenopus oocytes. The organization of the ovi sacs, fine structure of the oogenesis, vitellogenesis and formation of cocoons were studied in two freshwater leeches. Openear 3d models allow you to explore 8 unique anatomical specimens. The process is remarkably similar in all animals analyzed so far. Beginning january, 2003, goi mandated the use of 5 percent ethanol blend in petrol through its ambitious ethanol blending program the availability of biomass in india is estimated at about 500 million tons per year covering residues from agriculture, agroindustrial, forestry and plantations nearly 50 million. Even though lipids are mainly stored in the hepatopancreas, which is located in the cephalothorax vogt et al. J p sumpter and s jobling department of biology and biochemistry, brunel university, uxbridge, middlesex, united kingdom. The egg in all animals is a larger cell in comparison to other type of cells. The cytoplasm is now full of lipoid drops and yolk production begins. In goldfish, on the other hand, when vitellogenesis commences, the egg has a diameter of 150 microns 0. Molecular characterisation and expression analysis of cathepsin d. In this study, we characterised the cathepsin d from the asian seabass lates calcarifer and examined its expression profile.
Read this article to get information on eggs and oogenesis in animal. Vitellogenesis article about vitellogenesis by the free. Vitellogenesis, oocyte maturation pattern, spawning rhythm. Mar 19, 2018 this is a differentiation phase where primary and secondary oocytes formation takes place. The nutrients stored in the ovulated egg must be sufficient to sustain progeny development from the time of fertilization to the onset of exogenous feeding. Vitellogenin composition in white perch and striped bass egg yolk. Crustaceans produce complex yolk proteins to meet the substrate and energy requirements of embryonic development.
Mechanisms and control of vitellogenesis in crustaceans. Vitellogenesis, vitellogenin vg synthesized in the fat body, transported by hemolymph, and taken up by maturing oocytes, is a prerequisite to egg production of many insects. Oogenesis meiotic previtellogenesis vitellogenesis premeiotic 4. Environmental cues pictured at the top indicate from left to right water temperature, daylength, rainy weather, conspecific males andor females, and xenoestrogens in the environment.
Mechanisms of egg yolk formation and implications on early life. Cognate ligands and oocyte receptors the binding site for vitellogenin is located on lipovitellin i received for publication, september 7, 1989 stefano stifanis, johannes nimpfs, and wolfgang j. Immersion in des strongly induced vitellogenin, as. Vitellogenesis the synthesis and storage of yolk in the developing female sexual cells of animals oocytes during oogenesis. Vitellogenesis definition, the process by which the yolk is formed and accumulated in the ovum. Raikhels from the department of entomology and program in cell and molecular biology, michigan state university. Vitellogenesis is the process of vitellus accumulation and involves massive heterosynthetic synthesis of the protein. Molecular characterisation and expression analysis of. Segmentations of scala tympani, scala vestibuli, malleus, incus, stapes, facial nerve, chorda tympani, tympanic membrane, external auditory canal, sigmoid sinus and dura, carotid artery.
As the cytoplasmic and nuclear changes occur during oogenesis chaps. In mammals, this programming is established perinatally, and exposure. This compound has previously been shown to be a potent stimulator of vitellogenesis in x. Vitellogenesis and postvitellogenic maturation of the.