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FERTILIZATION, CLEVEAGE and IMPLANTATION 1Lusia Hayati

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FERTILIZATION, CLEVEAGE and IMPLANTATION 1Lusia Hayati [DOCUMENT TITLE] FERTILIZATION, CLEVEAGE AND IMPLANTATION 1Lusia Hayati 1Department of Biology, Faculty of Medicine, University of Sriwijaya Email : [email protected] Abstract Most of the livestock in Indonesia are still conventional or traditional farms, where the quality of the seeds, the use of technology and the skills of farmers are still relatively low, thus affecting the productivity and genetic quality of livestock. Therefore it is necessary to have knowledge about livestock reproduction that discusses fertilization, cleveage and implantation. Fertilization or fertilization (singami) is the fusion of two gametes which can be a nucleus or nucleus cells to form a single cell (zygote) or fusion of the nucleus. the process starts with the preparation of ovum cells and spermatozoa; penetration; core incorporation; and early zygote cleavage. Fertilization phase is the meeting between sperm cells and ovum cells and will produce zygote. Zygote will perform cell division (cleavage). The zygote then undergoes growth and development through stages, namely division, gastrulation, and organogenesis. Implantation or also known as oxidation is the process of implanting the embryo, which is the result of conception, into the uterine wall (endometrium) to further develop. Keyword : fertilization, cleveage, implantation, reproduction 138 Fertilization or fertilization (singami) 1. Introduction is the fusion of two gametes which can Low productivity and genetic quality of be a nucleus or nucleus cells to form a livestock is still a problem in the world of single cell (zygote) or fusion of the livestock in Indonesia. This situation occurs nucleus. Usually involves the fusion of because most of the livestock in Indonesia the cytoplasm (plasmogamy) and the are still conventional or traditional farms, fusion of nuclear material (karyogamy). where the quality of the seeds, the use of With meiosis, the zygote forms a technology and skills of farmers are still fundamental feature of most eukaryotic relatively low, livestock raising is done on an sexual cycles, and basically the fused occasional basis (not a major economic gametgamete is haploid. When both are source) with 1-3 livestock ownership. motile as in plants, then fertilization is Reproduction is a physiological process in called isogamy, if they differ in size but living things to produce offspring. Higher are similar in shape it is called animals reproduce sexually and the anisogamy, if one is not motile (and reproduction process includes several usually larger) it is called oogamy. This is physiological levels that include very typical of some plants, animals, and complex functions and are integrated most fungi. In some gymnophytes and between one process and another. These all antophytes, the gametes are not physiological levels include the formation of flagellated, and the pollen tube is sex cells (gametes), release of functionally involved in the fertilization process. differentiated gamete cells, mating to bring together male and female gametes, 2. Types of Fertilization fertilization, fusion between the two 1. External fertilization (typical in pronuclei, growth, differentiation and aquatic animals): the gametes are development of the zygote until birth. removed from the body before Normal. The field of livestock productivity fertilization cannot be separated from the reproductive 2. Internal fertilization (typical for process. Reproductive success is a reflection adaptation to life on land): sperm of the success of a livestock business. are inserted into the female Population development is highly dependent reproductive area which is then on broodstock and quality seedlings as well followed by fertilization. After as the large number of cows born. This is of fertilization, the egg forms a course highly supported by optimal fertilization membrane to prevent reproductive management. Production and further sperm entry. Sometimes the reproduction are closely related to the sperm is needed only to activate the development and availability of livestock. egg (Anonymous, 2008) Failure of a livestock to become pregnant in one or more matings will eliminate the 3. Fertilization process product of conception in one or more Fertilization occurs when gestation periods. spermatozoa cells are released and can Based on the description above, it is fertilize the ovum in the ampulla of the necessary to have knowledge about the fallopian tube. As many as 300 million science of livestock reproduction, especially spermatozoa are ejaculated into the discussing the issue of fertilization, cleaveage female genital tract. About 1 million can and implantation to help improve the swim through the cervix, hundreds of genetic quality of an animal. which can reach the fallopian tube and only 1 can fertilize an egg. Spermatozoa 2. DISCUSSION cells have a life span of about 48 hours (Cambridge, 1998). Before fertilizing an 2.1 FERTILIZATION egg, spermatozoa must go through the 1. Definition of fertilization 139 capacitation and acrosome correction division occurs in prokaryotic cells stages first. Capacitation is a period of such as bacteria. The purpose of this adjustment in the female reproductive division is to form new offspring. tract, lasting about 7 hours. During that b. Mitotic Cell Division time a glycoprotein sheath from the Mitotic division, division which cement plasma is removed from the results in two daughter cells that are plasma membrane which encloses the the same as the parent, meaning that acrosome region of the spermatozoa. these daughter cells can divide again. Meanwhile, the acrosome reaction In Humans, this division occurs in occurs after the attachment of somatic meristem cells (young body spermatozoa to the zona pellucida. This cells). This process takes place reaction causes the release of enzymes through structured and orderly needed to penetrate the zona pellucida stages, unlike Amitosis which occurs contained in the acrosome (Sadler, spontaneously. 1996). Oocytes (ovum) will reach the tube more than one hour after This mitotic division goes through ovulation. The ovum is surrounded by two stages, namely Kariokinesis and the corona of small cells and the zona Cytokinesis. pellucida which will filter the existing 1. Kariokinesis spermatozoa cells so that only one cell This process shows a striking can penetrate the ovum. difference in each phase and aims to After the spermatozoa penetrates divide the core material, as for the the ovum, it combines its core material changes as follows: and stores the usual double Interphase chromosome complement. This At this stage the cells do not chromosome contains all the genetic divide. The nucleus consists of information which will be passed on to ribosomal RNA and is the site of the offspring (Canbridge, 1998). protein synthesis and dark matter The fertilized egg will form a zygote known as chromatin or the form of which continues to divide by mitosis chromosome strings so that the into two, four, eight, sixteen and so on. shape of the chromosomes cannot be seen clearly. At one end of the cell, 2.2 Cleveage there are 2 pairs of proteins called 1. Definition of Cell Division centrioles, but in plants, centriosoles Cell division is the process of dividing do not appear. a parent cell into two or more daughter Prophase cells. Cell division is usually a cycle of At this stage the DNA begins to be small cells which will lead to the next packaged into chromosomes. The major cycle. chromosomes begin to shorten and 2. Types of cell division and their thicken. In animal cells the centrioles processes divide and each move to the opposite a. Amitotic cell division (binary fission) pole and a spindle thread is formed Amitotic cell division is also called which is connected to the poles. direct cell division or does not go Eventually the chromosome appears through certain stages, this process to consist of two chromatids also takes place spontaneously, or is attached to the centromere. The called binary fission. This process nucleolus is lost and the nuclear does not involve chromosomes why membrane is destroyed. is that? Because the DNA is present . Metaphase in such a small amount and size that In this phase, the chromosomes it cannot be packaged, most of this move into a line called the equator. 140 In addition, threads called spindles Interphase appear and are attached to the At interphase, the cell is in the centromere of each chromosome. preparatory stage for division. This spindle connects the The preparation is the DNA chromosomes to the 2 opposite poles doubling of one copy into two of the centricoles copies (the same as in the . Anaphase mitotic interphase). The final Each centromere that binds the stage of interphase is the chromatid divides together and the presence of two DNA copies that chromatid moves towards the are ready to be packed into cleavage pole, producing paired chromosomes copies of the chromosomes. - Prophase 1. At this stage the . Telophase following process occurs At this stage the chromosomes - Leptotene is the stage where the begin to organize to form a separate chromatin threads turn into nucleus and are surrounded by chromosomes. This is done by members of the nucleus. Cleavage self-compacting. Burrow / groove division narrows and - Zygotene / Zigonema, at this over time divides cells. In contrast, in stage, homolong chromatids pair plants, cleavage occurs with a cell up or synapses to form bivalents. plate rather than a cleavage burrow. The centrosome splits into 2 centrioles and moves to the 2. Cytokinesis opposite pole. During cytokinesis, the cytoplasm - Pakiten / Pakinema, the of animal cells is divided into two by chromosomes are then the formation of a contractile ring duplicated into 4 at this stage formed by actin and myosin in the and are called tetrads center of the cell. This contractile (homologous chromosomes that ring causes the formation of a multiply so that there are 4 cleavage groove which will eventually paired chromatids). At this stage, produce two daughter cells. Each of gene recombination often occurs these daughter cells that form through the cross-transfer contains a cell nucleus, along with process. cell organelles.
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