{"id":41348,"date":"2023-08-03T15:00:57","date_gmt":"2023-08-03T09:15:57","guid":{"rendered":"https:\/\/microbenotes.com\/oogenesis-ovulation-ovarian-cycle\/"},"modified":"2023-08-03T15:00:57","modified_gmt":"2023-08-03T09:15:57","slug":"oogenesis-ovulation-ovarian-cycle","status":"publish","type":"post","link":"https:\/\/microbenotes.com\/oogenesis-ovulation-ovarian-cycle\/","title":{"rendered":"Oogenesis \/ Ovulation \/ Ovarian cycle- Definition, Phages, Process"},"content":{"rendered":"\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_65 counter-hierarchy ez-toc-counter ez-toc-custom ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title \" >Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #0a0a0a;color:#0a0a0a\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #0a0a0a;color:#0a0a0a\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/microbenotes.com\/oogenesis-ovulation-ovarian-cycle\/#oogenesis-definition\" title=\"Oogenesis Definition\">Oogenesis Definition<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/microbenotes.com\/oogenesis-ovulation-ovarian-cycle\/#a-follicular-phase\" title=\"A. Follicular phase\">A. Follicular phase<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/microbenotes.com\/oogenesis-ovulation-ovarian-cycle\/#b-ovulation-phase\" title=\"B. Ovulation phase\">B. Ovulation phase<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/microbenotes.com\/oogenesis-ovulation-ovarian-cycle\/#c-luteal-phase\" title=\"C. Luteal Phase\">C. Luteal Phase<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/microbenotes.com\/oogenesis-ovulation-ovarian-cycle\/#refrences\" title=\"Refrences\">Refrences<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"oogenesis-definition\"><\/span><strong>Oogenesis Definition<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Oogenesis is the <a href=\"https:\/\/microbenotes.com\/female-reproductive-system\/\">female<\/a> version of gametogenesis. It is the process of formation of female gamete or ovum, necessary for sexual reproduction.<\/p>\n\n\n\n<ul><li>The process of oogenesis starts pre-natally, i.e. before the birth of the female child. It begins about 8-20 weeks after the fetus has begun to grow and goes on until the birth of the child.<\/li><li>Thus, a newborn female child already has all the egg cells that are to be released from the ovaries during the reproductive life of the female. These cells are termed primary ova.<\/li><li>The primary ova remain dormant until ovulation and become matured afterward. Some of these cells take as long as 40 years to mature while some reach maturation.<\/li><li>The reproductive life of a female is characterized by the monthly periodic changes that occur in the release of sexual hormones as well as changes in the structure of ovaries as well as other sexual organs. This cyclic process is termed the female monthly sexual cycle.<\/li><li>The process of oogenesis is described by the ovarian cycle, which is involved in the formation and maturation of female gamete.<\/li><\/ul>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1355\" height=\"733\" src=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/11\/Oogenesis-or-Ovulation-or-Ovarian-cycle.jpeg\" alt=\"Oogenesis or Ovulation or Ovarian cycle\" class=\"wp-image-31826\" srcset=\"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/11\/Oogenesis-or-Ovulation-or-Ovarian-cycle.jpeg 1355w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/11\/Oogenesis-or-Ovulation-or-Ovarian-cycle-300x162.jpeg 300w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/11\/Oogenesis-or-Ovulation-or-Ovarian-cycle-1024x554.jpeg 1024w, https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/11\/Oogenesis-or-Ovulation-or-Ovarian-cycle-768x415.jpeg 768w\" sizes=\"(max-width: 1355px) 100vw, 1355px\" \/><\/figure>\n\n\n\n<p>Image Source:&nbsp;<a href=\"https:\/\/www.britannica.com\/science\/ovulation\" target=\"_blank\" rel=\"noopener noreferrer\">Britannica<\/a>, Created with BioRender.com.<\/p>\n\n\n\n<p>The ovarian cycle is divided into three phases:<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"a-follicular-phase\"><\/span><strong>A. Follicular phase<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<ul><li>After puberty, as a result of the release of a large amount of FSH and LH by the pituitary, the ovaries with the follicles start to grow.<\/li><li>During the first stage, the targeted follicular cells enlarge up to two-fold to three-fold in diameter. These enlarged follicular cells are termed primordial follicles.<\/li><li>After a few days, the level of FSH surpasses LH which accelerates the growth of 6-10 primary follicles that compete for dominance. Under the influence of FSH, these cells develop layers of granulosa cells as well as express the LH receptors on the granulosa cells.<\/li><li>The second layer of cells called theca develops around these follicles which can produce other sex hormones like estrogen and progesterone.<\/li><li>LH from the pituitary and the estrogen within the follicles cause accelerated growth of the primary follicles into vesicular follicles.<\/li><li>The ovum present inside the follicles develops aggressively increasing in size another threefold to four-fold. After a week or more of growth, one of the follicles starts outgrowing other follicles (a process called atresia). The reason behind the process of atresia is not yet known; however, it is imperative as it prevents more than one child during pregnancy.<\/li><li>The single follicle further increases in size and forms the mature follicle.<\/li><li>The primary oocyte or ovum within the ovary remains as it is until it\u2019s time to leave the ovary.<\/li><li>The oocyte then undergoes meiotic division where the nucleus splits into two dividing the number of chromosomes in half. One of the two cells formed is usually larger than the other and is called the secondary oocyte, while the smaller one is called a polar body.<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"b-ovulation-phase\"><\/span><strong>B. Ovulation phase<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<ul><li>Ovulation in women with regular 28 days sexual cycles occurs 14 days after the onset of menstruation. Few days before ovulation the follicle starts to swell with a protruding center called the stigma.<\/li><li>The in-surge of LH hormone and the release of estrogen from the follicle degrades the cells at the stigma and results in a hole. The secondary oocyte leaves the follicle through the hole and reaches the peritoneal cavity. The secondary oocyte then reaches the fallopian tube through the fimbriae.<\/li><li>It takes a few days for the transport of the ovum. The movement within the fallopian tube is aided by the peristaltic movement of muscles in the walls of the oviduct.<\/li><li>The movement, however, also depends on the level of progesterone and estrogen. Progesterone accelerates the movement while estrogen arrests the movement of the ovum.<\/li><li>If there is left-right coordination between the ovaries is not yet known. However, occasionally, both the ovaries release an ovum, which results in the formation of fraternal twins.<\/li><li>If a sperm fertilizes the oocyte, it develops into a mature ovum. If fertilization doesn\u2019t occur, the secondary oocyte degenerates within the fallopian tube.<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"c-luteal-phase\"><\/span><strong>C. Luteal Phase<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<ul><li>The luteal phase is the last phase of the ovarian cycle and it corresponds with the secretory phase of the uterine cycles.<\/li><li>During the first few hours of ovulation, the remaining follicular cell, including the granulosa and theca develop into lutein cells. This cell then becomes filled with lipid components that give it a yellow appearance. The total mass of the cell is called corpus luteum.<\/li><li>Corpus luteum produces progesterone that inhibits the release of FSH and LH by the pituitary. Consequently, the concentration of FSH and LH falls over time and the corpus luteum degenerates.<\/li><li>The falling levels of progesterone then trigger menstruation. The process from the start of ovulation to the withdrawn of progesterone takes around two weeks. Even though the sexual cycle in all women is not the same; the duration of the luteal phase remains more or less the same in all women.<\/li><li>In case of a successful pregnancy, the degeneration of the corpus luteum is prevented by the release of human chorionic gonadotropin(hCG) from the placenta. Corpus luteum is essential to produce progesterone which maintains the new pregnancy.<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"refrences\"><\/span><strong>Refrences<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<ul><li>Hall JE and Guyton AC. (2011) Textbook of Medical Physiology. Twelfth Edition. Elsevier Saunders.<\/li><li>Waugh A and Grant A. (2004) Anatomy and Physiology. Ninth Edition. Churchill Livingstone.<\/li><li>Marieb EN and Hoehn K. (2013) Human Anatomy and Physiology. Ninth Edition. Pearson Education, Inc.<\/li><li>Rastogi SC. (2007) Essentials of Human Physiology. Fourth Edition. New Age International Limited.<\/li><li>https:\/\/www.britannica.com\/science\/oogenesis<\/li><li>https:\/\/www.britannica.com\/science\/ovulation<\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Oogenesis Definition Oogenesis is the female version of gametogenesis. It is the process of formation of female gamete or ovum, necessary for sexual reproduction. The process of oogenesis starts pre-natally, &#8230; <a title=\"Oogenesis \/ Ovulation \/ Ovarian cycle- Definition, Phages, Process\" class=\"read-more\" href=\"https:\/\/microbenotes.com\/oogenesis-ovulation-ovarian-cycle\/\" aria-label=\"Read more about Oogenesis \/ Ovulation \/ Ovarian cycle- Definition, Phages, Process\">Read more<\/a><\/p>\n","protected":false},"author":11,"featured_media":31826,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6190],"tags":[5584,5320,5816],"custom":{"td_video":"","featured_image":"https:\/\/microbenotes.com\/wp-content\/uploads\/2020\/11\/Oogenesis-or-Ovulation-or-Ovarian-cycle.jpeg","author":{"name":"Anupama Sapkota","avatar":"https:\/\/secure.gravatar.com\/avatar\/0e9c86afc1670c49efeb260138ec905b?s=96&d=mm&r=g"},"categories":[{"term_id":6190,"name":"Human Anatomy and Physiology","slug":"anatomy-and-physiology","term_group":0,"term_taxonomy_id":6190,"taxonomy":"category","description":"<strong>Human anatomy is the science that deals with the physical morphology and structure of the human body.<\/strong>\r\n\r\nHuman anatomy is further divided into two groups; gross anatomy and microscopic anatomy. Gross anatomy involves study related to anatomical structures that can be seen with unaided eyes, while microscopic anatomy is the study of minute anatomical structures, histology, and cytology.\r\nHumans belong to the Subphylum Vertebrate of the Phylum Chordata as they have the characteristic internal skeleton with a backbone of vertebrae.\r\nOther typical mammalian structures in humans include hair, mammary glands, and highly developed sense organs.\r\nBesides, among mammals, humans have a predominantly two-legged (bipedal) posture, along with a highly developed intellectual.\r\nThe chemical composition of the human body is composed of water and organic compounds like proteins, carbohydrates, and lipids.\r\nThe human body is composed of specialized systems for different purposes; the digestive system for digestion, the respiratory system for respiration, the reproductive system for reproduction, and the skeletal and muscular system for movement.\r\nCells are the fundamental units of the human body consisting of trillions of cells in the body. The cells together form tissues.\r\nFour basic types of tissues are found in humans, each of which is specialized for a particular purpose; epithelial tissue for covering the body, muscular tissue for movement, nerve tissues for signaling, and connective tissue for transport of nutrients.\r\nThe following organization of the human body is organs. An organ is composed of a group of specialized tissues from a structural and functional unit.\r\nOrgans are followed by the system as the final organization of the human body. The body includes nine major organ systems, each composed of various organs and tissues that work together as a functional unit.\r\nInformation on human anatomy is essential during the analysis of signs of symptoms of different diseases and disease diagnoses.\r\nIt also allows an understanding of the relationship between different organ systems and the changes occurring in the body's anatomy during growth.\r\n\r\n<strong>Human physiology is a branch of natural science that deals with the functioning of the human body.<\/strong>\r\n\r\nIt includes various physiological activities like digestion, respiration, spermatogenesis, oogenesis, and excretion, all of which occur in a coordinated way between various organs and systems.\r\nPhysiology includes the mechanical, physical, bioelectrical, and biochemical functioning of a healthy human body.\r\nA normal human body works as a result of the regulated system of networking between different systems. These interactions work towards maintaining homeostasis.\r\nThe concept of homeostasis is important in human physiology as it explains that the internal environment of an organism moves in a direction to maintain an equilibrium.\r\nIn the human body, homeostasis is maintained at the system level with each system trying to maintain its homeostasis.\r\nHuman physiology, like human anatomy, describes the mechanisms from the molecular to the cellular level, integrating the working of the entire body.\r\nBased on the information obtained via studies done on human physiology, it is understood that the cells, tissues, organs, and systems together work to maintain a healthy human body.\r\nBesides, certain compounds or chemicals produced in the body like enzymes and hormones also aid in the process of human physiology.\r\nA slight change in the working of a single organ in the body might affect the working of the entire body overall.\r\nHuman physiology is closely related to human anatomy where the anatomy of an organ or tissue plays a significant role in the physiology of the said organ or tissue.\r\nHuman physiology is also interrelated with clinical medicine and microbiology where different microorganisms found within the body aid in different processes like bacteria in the gut producing acid and other enzymes that aid in digestion.\r\nDuring the life cycle of humans, the body undergoes multiple changes which are influenced by changes in anatomy and changes in environmental factors.\u00a0 The physiology of the body thus adapts to such changes to maintain homeostasis.","parent":0,"count":74,"filter":"raw","cat_ID":6190,"category_count":74,"category_description":"<strong>Human anatomy is the science that deals with the physical morphology and structure of the human body.<\/strong>\r\n\r\nHuman anatomy is further divided into two groups; gross anatomy and microscopic anatomy. Gross anatomy involves study related to anatomical structures that can be seen with unaided eyes, while microscopic anatomy is the study of minute anatomical structures, histology, and cytology.\r\nHumans belong to the Subphylum Vertebrate of the Phylum Chordata as they have the characteristic internal skeleton with a backbone of vertebrae.\r\nOther typical mammalian structures in humans include hair, mammary glands, and highly developed sense organs.\r\nBesides, among mammals, humans have a predominantly two-legged (bipedal) posture, along with a highly developed intellectual.\r\nThe chemical composition of the human body is composed of water and organic compounds like proteins, carbohydrates, and lipids.\r\nThe human body is composed of specialized systems for different purposes; the digestive system for digestion, the respiratory system for respiration, the reproductive system for reproduction, and the skeletal and muscular system for movement.\r\nCells are the fundamental units of the human body consisting of trillions of cells in the body. The cells together form tissues.\r\nFour basic types of tissues are found in humans, each of which is specialized for a particular purpose; epithelial tissue for covering the body, muscular tissue for movement, nerve tissues for signaling, and connective tissue for transport of nutrients.\r\nThe following organization of the human body is organs. An organ is composed of a group of specialized tissues from a structural and functional unit.\r\nOrgans are followed by the system as the final organization of the human body. The body includes nine major organ systems, each composed of various organs and tissues that work together as a functional unit.\r\nInformation on human anatomy is essential during the analysis of signs of symptoms of different diseases and disease diagnoses.\r\nIt also allows an understanding of the relationship between different organ systems and the changes occurring in the body's anatomy during growth.\r\n\r\n<strong>Human physiology is a branch of natural science that deals with the functioning of the human body.<\/strong>\r\n\r\nIt includes various physiological activities like digestion, respiration, spermatogenesis, oogenesis, and excretion, all of which occur in a coordinated way between various organs and systems.\r\nPhysiology includes the mechanical, physical, bioelectrical, and biochemical functioning of a healthy human body.\r\nA normal human body works as a result of the regulated system of networking between different systems. These interactions work towards maintaining homeostasis.\r\nThe concept of homeostasis is important in human physiology as it explains that the internal environment of an organism moves in a direction to maintain an equilibrium.\r\nIn the human body, homeostasis is maintained at the system level with each system trying to maintain its homeostasis.\r\nHuman physiology, like human anatomy, describes the mechanisms from the molecular to the cellular level, integrating the working of the entire body.\r\nBased on the information obtained via studies done on human physiology, it is understood that the cells, tissues, organs, and systems together work to maintain a healthy human body.\r\nBesides, certain compounds or chemicals produced in the body like enzymes and hormones also aid in the process of human physiology.\r\nA slight change in the working of a single organ in the body might affect the working of the entire body overall.\r\nHuman physiology is closely related to human anatomy where the anatomy of an organ or tissue plays a significant role in the physiology of the said organ or tissue.\r\nHuman physiology is also interrelated with clinical medicine and microbiology where different microorganisms found within the body aid in different processes like bacteria in the gut producing acid and other enzymes that aid in digestion.\r\nDuring the life cycle of humans, the body undergoes multiple changes which are influenced by changes in anatomy and changes in environmental factors.\u00a0 The physiology of the body thus adapts to such changes to maintain homeostasis.","cat_name":"Human Anatomy and Physiology","category_nicename":"anatomy-and-physiology","category_parent":0}]},"_links":{"self":[{"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/posts\/41348"}],"collection":[{"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/comments?post=41348"}],"version-history":[{"count":0,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/posts\/41348\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/media\/31826"}],"wp:attachment":[{"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/media?parent=41348"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/categories?post=41348"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/microbenotes.com\/wp-json\/wp\/v2\/tags?post=41348"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}