Are you over 18 and want to see adult content?
More Annotations
![A complete backup of egaleofencing.gr](https://www.archivebay.com/archive/fc8414fd-18b4-4b32-a1ef-f82621d71f66.png)
A complete backup of egaleofencing.gr
Are you over 18 and want to see adult content?
![A complete backup of helium-connect.fr](https://www.archivebay.com/archive/3270e1c1-fafd-4267-a20d-9213ca440838.png)
A complete backup of helium-connect.fr
Are you over 18 and want to see adult content?
![A complete backup of styles101.homestead.com](https://www.archivebay.com/archive/21798ef0-9578-4881-a757-c1fae7f2a654.png)
A complete backup of styles101.homestead.com
Are you over 18 and want to see adult content?
![A complete backup of yapiprefabrik.net](https://www.archivebay.com/archive/cd63eb33-e852-4bcd-9180-c588ef8d7e24.png)
A complete backup of yapiprefabrik.net
Are you over 18 and want to see adult content?
![A complete backup of worldgolfimax.com](https://www.archivebay.com/archive/b6696a5f-1a3c-46b9-9bc2-567e45ede38a.png)
A complete backup of worldgolfimax.com
Are you over 18 and want to see adult content?
![A complete backup of musicadeseries.com](https://www.archivebay.com/archive/5d2d3733-fbdf-46fa-9e29-11966edee873.png)
A complete backup of musicadeseries.com
Are you over 18 and want to see adult content?
Favourite Annotations
![A complete backup of laser-gadgets.com](https://www.archivebay.com/archive2/2ba91498-b6e1-4bcb-b930-cc96ea9c1904.png)
A complete backup of laser-gadgets.com
Are you over 18 and want to see adult content?
![A complete backup of bucherhydraulics.com](https://www.archivebay.com/archive2/d198a5fc-3806-4779-9305-79ef0a1a0741.png)
A complete backup of bucherhydraulics.com
Are you over 18 and want to see adult content?
![A complete backup of firstnations.org](https://www.archivebay.com/archive2/4671e4aa-6583-4ab1-858e-90f58173b0b4.png)
A complete backup of firstnations.org
Are you over 18 and want to see adult content?
![A complete backup of knowablemagazine.org](https://www.archivebay.com/archive2/a7badf60-e06b-42e1-98d7-59169bc2b127.png)
A complete backup of knowablemagazine.org
Are you over 18 and want to see adult content?
![A complete backup of isaacsandisaacs.com](https://www.archivebay.com/archive2/57b8cd86-4c27-47cc-a694-6ce376fb1c19.png)
A complete backup of isaacsandisaacs.com
Are you over 18 and want to see adult content?
Text
ACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantationTHE CARDINAL SYSTEM
The cardinal system. The cardinal veins form as the basis for the intraembryonic venous part of the circulatory system. Various venous systems appear in various stages of the embryogenesis and partially disappear again. Very early in the development two paired systemsappear:
DESCENT OF THE TESTES Descent of the testes. Between the 3rd month of pregnancy and its end the testes become transferred from the lumbar area (ventro-medial to the mesonephros) into the future scrotum. This transfer is due to a combination of growth processes and hormonal influences ( 7 ). The gubernaculum testis also plays a decisive role in this phenomenon. SWITCHING OVER AT BIRTH, CIRCULATION SYSTEM BEFORE / AFTER Circulation system after birth. Immediately after birth the newborn must begin to breathe regularly. The first breaths are difficult because the lungs are still filled with fluid (ca. 50 ml) and at birth the alveoli are collapsed. Half (50%) of this fluid is resorbed via the lymph vessels, a quarter is pressed out by the birth process (nottrue
DEVELOPMENT OF THE UMBILICAL CORD Development of the umbilical cord. The umbilical cord is formed when the body stalk and the ductus omphalo-entericus as well as the umbilical coelom are enveloped by the spreading amnion between the 4th and 8th week. Finally, when the membranes of the amniotic cavity come into contact with those of the chorionic cavity and the two extra POUMON, MODIFICATION À LA NAISSANCE, SITUATIONTRANSLATE THIS PAGE Situation de la circulation après la naissance. Le nouveau-né doit commencer à respirer immédiatement après la naissance. Les premiers cycles respiratoires sont pénibles, les poumons étant encore remplis de liquide (env. 50ml) et les alvéoles collabées au moment de la naissance. La moitié (50 %) du liquide est résorbé par les THE EXTERNAL GENITALIA, INDIFFERENT STAGE Indifferent stage. Quiz. Quiz 27. During the third week the cloacal membrane is formed and lies below the umbilical cord. In the fourth week, as the lower abdominal wall is being formed, the cloacal membrane is shifted caudally by immigrating mesenchyma coming from various sources. It is now delimited in front by a prominentmesenchymatous
LES PLACODES ET LES ORGANES DES SENS Les placodes correspondent à des épaississements de l'ectoderme rostral.Chaque placode est formée par un groupe de cellules qui migre dans le mésoblaste sous-jacent pour former un organe spécifique (cellules sensorielles et neurones périphériques), suite à son induction par la région adjacente du tube neural. Par extension on peut assimiler la plaque neurale à une très grandeACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantationTHE CARDINAL SYSTEM
The cardinal system. The cardinal veins form as the basis for the intraembryonic venous part of the circulatory system. Various venous systems appear in various stages of the embryogenesis and partially disappear again. Very early in the development two paired systemsappear:
DESCENT OF THE TESTES Descent of the testes. Between the 3rd month of pregnancy and its end the testes become transferred from the lumbar area (ventro-medial to the mesonephros) into the future scrotum. This transfer is due to a combination of growth processes and hormonal influences ( 7 ). The gubernaculum testis also plays a decisive role in this phenomenon. SWITCHING OVER AT BIRTH, CIRCULATION SYSTEM BEFORE / AFTER Circulation system after birth. Immediately after birth the newborn must begin to breathe regularly. The first breaths are difficult because the lungs are still filled with fluid (ca. 50 ml) and at birth the alveoli are collapsed. Half (50%) of this fluid is resorbed via the lymph vessels, a quarter is pressed out by the birth process (nottrue
DEVELOPMENT OF THE UMBILICAL CORD Development of the umbilical cord. The umbilical cord is formed when the body stalk and the ductus omphalo-entericus as well as the umbilical coelom are enveloped by the spreading amnion between the 4th and 8th week. Finally, when the membranes of the amniotic cavity come into contact with those of the chorionic cavity and the two extra POUMON, MODIFICATION À LA NAISSANCE, SITUATIONTRANSLATE THIS PAGE Situation de la circulation après la naissance. Le nouveau-né doit commencer à respirer immédiatement après la naissance. Les premiers cycles respiratoires sont pénibles, les poumons étant encore remplis de liquide (env. 50ml) et les alvéoles collabées au moment de la naissance. La moitié (50 %) du liquide est résorbé par les LES PLACODES ET LES ORGANES DES SENS Les placodes correspondent à des épaississements de l'ectoderme rostral.Chaque placode est formée par un groupe de cellules qui migre dans le mésoblaste sous-jacent pour former un organe spécifique (cellules sensorielles et neurones périphériques), suite à son induction par la région adjacente du tube neural. Par extension on peut assimiler la plaque neurale à une très grande THE EXTERNAL GENITALIA, INDIFFERENT STAGE Indifferent stage. Quiz. Quiz 27. During the third week the cloacal membrane is formed and lies below the umbilical cord. In the fourth week, as the lower abdominal wall is being formed, the cloacal membrane is shifted caudally by immigrating mesenchyma coming from various sources. It is now delimited in front by a prominentmesenchymatous
HOME
HUMAN EMBRYOLOGY. Embryogenesis. Organogenesis. Online course in embryology for medicine students. developed by the universities of Fribourg, Lausanne and Bern (Switzerland) with the support of the Swiss Virtual Campus. THE VARIOUS PLACENTA TYPES The limited contact surface between mother and child, as occurs with a discoid placenta, is compensated by an intensive interdigitation between the two surfaces.In humans one finds the villus placenta that is constructed out of a highly complex system of interdigital folds (septa). The septa are thin, long and branched. The section comprised between two septa is called a cotyledon.CHANGES AT BIRTH
Changes at birth. With birth, a change from parallel flow through the heart to a serial one gradually takes place. The following changes must occur: The gas exchange takes place in the baby's lungs. By cutting the umbilical cord, the placental circulation system is switched off. The fetal heart shunts become closed. PATHOLOGIES OF THE PLACENTA A web-based training in medical embryology. The pathologies of the placenta cover a large spectrum of diverse diseases that range from anomalies of the form and the implantation, over fetal (fetal erythroblastosis) and maternal (diabetes, pregnancy toxaemia, eclampsia) complications, and all the way to tumors and infections. DEVELOPMENT OF THE PLACENTAL VILLI Connections between maternal and fetal tissues. Maternal and fetal tissues form two units that are closely bound together at the placental level. The fetal part of the placenta is made up of the chorionic plate with its placental villi, the cytotrophoblast layer and the intervillous spaces. The chorionic plate (great part of theplacenta on the
RIGHT CARDIAC OBSTRUCTION (WITHOUT SHUNT) Cardiac abnormalities can thus be subdivided into the following three groupings: Anomalies without shunt. Anomalies with left-right shunt (normally without cyanosis) Anomalies with right-left shunt (with cyanosis --> mixed blood ) Besides auscultation (with the stethoscope) echocardiography is the most frequently applied diagnostic method for MIDGUT; INTRODUCTION; INTESTINAL ROTATION Intestinal rotation. In stage 13, ca. 32 days, 13 the midgut begins to extend into the umbilical coelom and forms the umbilical loop, whereby initially from the apex only a wide connection to the umbilical vesicle exists. In the further development this junction becomes 10.3 PLACENTAL BLOOD CIRCULATION The placental circulation brings into close relationship two circulation systems: the maternal and the fetal. The supply of blood to the placenta is influenced by various factors, especially by the arterial blood pressure, uterine contractions, tobacco abuse, medications and hormones. Placental blood flow is increased at termand amounts to 500
THE PATH OF THE SPERM CELLS TO THE OOCYTE The path that the sperm cells must travel from the portio to their meeting with the oocyte in the ampullary part of the fallopian tube is 13-15 cm long. Along this stretch, sperm cells go through a further maturation process, the so-called capacitation. The mechanisms that guide the sperm cells to the oocyte have not been researched in all THE EJACULATION AND THE EJACULATE The ejaculation is brought about through rhythmic contractions of the deferent duct that come in waves and through supporting contractions of the pelvic musculature. The purpose of the coital ejaculation is to deposit spermatozoa, which are largely immobile having come from storage in the cauda of the epididymis, into the rear part of the vaginal cavity, i.e., near the external opening of theACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantationTHE CARDINAL SYSTEM
The cardinal system. The cardinal veins form as the basis for the intraembryonic venous part of the circulatory system. Various venous systems appear in various stages of the embryogenesis and partially disappear again. Very early in the development two paired systemsappear:
DESCENT OF THE TESTES Descent of the testes. Between the 3rd month of pregnancy and its end the testes become transferred from the lumbar area (ventro-medial to the mesonephros) into the future scrotum. This transfer is due to a combination of growth processes and hormonal influences ( 7 ). The gubernaculum testis also plays a decisive role in this phenomenon. SWITCHING OVER AT BIRTH, CIRCULATION SYSTEM BEFORE / AFTER Circulation system after birth. Immediately after birth the newborn must begin to breathe regularly. The first breaths are difficult because the lungs are still filled with fluid (ca. 50 ml) and at birth the alveoli are collapsed. Half (50%) of this fluid is resorbed via the lymph vessels, a quarter is pressed out by the birth process (nottrue
DEVELOPMENT OF THE UMBILICAL CORD Development of the umbilical cord. The umbilical cord is formed when the body stalk and the ductus omphalo-entericus as well as the umbilical coelom are enveloped by the spreading amnion between the 4th and 8th week. Finally, when the membranes of the amniotic cavity come into contact with those of the chorionic cavity and the two extra POUMON, MODIFICATION À LA NAISSANCE, SITUATIONTRANSLATE THIS PAGE Situation de la circulation après la naissance. Le nouveau-né doit commencer à respirer immédiatement après la naissance. Les premiers cycles respiratoires sont pénibles, les poumons étant encore remplis de liquide (env. 50ml) et les alvéoles collabées au moment de la naissance. La moitié (50 %) du liquide est résorbé par les THE EXTERNAL GENITALIA, INDIFFERENT STAGE Indifferent stage. Quiz. Quiz 27. During the third week the cloacal membrane is formed and lies below the umbilical cord. In the fourth week, as the lower abdominal wall is being formed, the cloacal membrane is shifted caudally by immigrating mesenchyma coming from various sources. It is now delimited in front by a prominentmesenchymatous
LES PLACODES ET LES ORGANES DES SENS Les placodes correspondent à des épaississements de l'ectoderme rostral.Chaque placode est formée par un groupe de cellules qui migre dans le mésoblaste sous-jacent pour former un organe spécifique (cellules sensorielles et neurones périphériques), suite à son induction par la région adjacente du tube neural. Par extension on peut assimiler la plaque neurale à une très grandeACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantationTHE CARDINAL SYSTEM
The cardinal system. The cardinal veins form as the basis for the intraembryonic venous part of the circulatory system. Various venous systems appear in various stages of the embryogenesis and partially disappear again. Very early in the development two paired systemsappear:
DESCENT OF THE TESTES Descent of the testes. Between the 3rd month of pregnancy and its end the testes become transferred from the lumbar area (ventro-medial to the mesonephros) into the future scrotum. This transfer is due to a combination of growth processes and hormonal influences ( 7 ). The gubernaculum testis also plays a decisive role in this phenomenon. SWITCHING OVER AT BIRTH, CIRCULATION SYSTEM BEFORE / AFTER Circulation system after birth. Immediately after birth the newborn must begin to breathe regularly. The first breaths are difficult because the lungs are still filled with fluid (ca. 50 ml) and at birth the alveoli are collapsed. Half (50%) of this fluid is resorbed via the lymph vessels, a quarter is pressed out by the birth process (nottrue
DEVELOPMENT OF THE UMBILICAL CORD Development of the umbilical cord. The umbilical cord is formed when the body stalk and the ductus omphalo-entericus as well as the umbilical coelom are enveloped by the spreading amnion between the 4th and 8th week. Finally, when the membranes of the amniotic cavity come into contact with those of the chorionic cavity and the two extra POUMON, MODIFICATION À LA NAISSANCE, SITUATIONTRANSLATE THIS PAGE Situation de la circulation après la naissance. Le nouveau-né doit commencer à respirer immédiatement après la naissance. Les premiers cycles respiratoires sont pénibles, les poumons étant encore remplis de liquide (env. 50ml) et les alvéoles collabées au moment de la naissance. La moitié (50 %) du liquide est résorbé par les THE EXTERNAL GENITALIA, INDIFFERENT STAGE Indifferent stage. Quiz. Quiz 27. During the third week the cloacal membrane is formed and lies below the umbilical cord. In the fourth week, as the lower abdominal wall is being formed, the cloacal membrane is shifted caudally by immigrating mesenchyma coming from various sources. It is now delimited in front by a prominentmesenchymatous
LES PLACODES ET LES ORGANES DES SENS Les placodes correspondent à des épaississements de l'ectoderme rostral.Chaque placode est formée par un groupe de cellules qui migre dans le mésoblaste sous-jacent pour former un organe spécifique (cellules sensorielles et neurones périphériques), suite à son induction par la région adjacente du tube neural. Par extension on peut assimiler la plaque neurale à une très grandeHOME
HUMAN EMBRYOLOGY. Embryogenesis. Organogenesis. Online course in embryology for medicine students. developed by the universities of Fribourg, Lausanne and Bern (Switzerland) with the support of the Swiss Virtual Campus. THE VARIOUS PLACENTA TYPES The limited contact surface between mother and child, as occurs with a discoid placenta, is compensated by an intensive interdigitation between the two surfaces.In humans one finds the villus placenta that is constructed out of a highly complex system of interdigital folds (septa). The septa are thin, long and branched. The section comprised between two septa is called a cotyledon.CHANGES AT BIRTH
Changes at birth. With birth, a change from parallel flow through the heart to a serial one gradually takes place. The following changes must occur: The gas exchange takes place in the baby's lungs. By cutting the umbilical cord, the placental circulation system is switched off. The fetal heart shunts become closed. PATHOLOGIES OF THE PLACENTA A web-based training in medical embryology. The pathologies of the placenta cover a large spectrum of diverse diseases that range from anomalies of the form and the implantation, over fetal (fetal erythroblastosis) and maternal (diabetes, pregnancy toxaemia, eclampsia) complications, and all the way to tumors and infections. DEVELOPMENT OF THE PLACENTAL VILLI Connections between maternal and fetal tissues. Maternal and fetal tissues form two units that are closely bound together at the placental level. The fetal part of the placenta is made up of the chorionic plate with its placental villi, the cytotrophoblast layer and the intervillous spaces. The chorionic plate (great part of theplacenta on the
RIGHT CARDIAC OBSTRUCTION (WITHOUT SHUNT) Cardiac abnormalities can thus be subdivided into the following three groupings: Anomalies without shunt. Anomalies with left-right shunt (normally without cyanosis) Anomalies with right-left shunt (with cyanosis --> mixed blood ) Besides auscultation (with the stethoscope) echocardiography is the most frequently applied diagnostic method for MIDGUT; INTRODUCTION; INTESTINAL ROTATION Intestinal rotation. In stage 13, ca. 32 days, 13 the midgut begins to extend into the umbilical coelom and forms the umbilical loop, whereby initially from the apex only a wide connection to the umbilical vesicle exists. In the further development this junction becomes 10.3 PLACENTAL BLOOD CIRCULATION The placental circulation brings into close relationship two circulation systems: the maternal and the fetal. The supply of blood to the placenta is influenced by various factors, especially by the arterial blood pressure, uterine contractions, tobacco abuse, medications and hormones. Placental blood flow is increased at termand amounts to 500
THE PATH OF THE SPERM CELLS TO THE OOCYTE The path that the sperm cells must travel from the portio to their meeting with the oocyte in the ampullary part of the fallopian tube is 13-15 cm long. Along this stretch, sperm cells go through a further maturation process, the so-called capacitation. The mechanisms that guide the sperm cells to the oocyte have not been researched in all THE EJACULATION AND THE EJACULATE The ejaculation is brought about through rhythmic contractions of the deferent duct that come in waves and through supporting contractions of the pelvic musculature. The purpose of the coital ejaculation is to deposit spermatozoa, which are largely immobile having come from storage in the cauda of the epididymis, into the rear part of the vaginal cavity, i.e., near the external opening of theACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
THE EMBRYOBLAST
The embryoblast. On the 4th or 5th day 3 the embryoblast consists of a double-layered embryonic disk. The outer cylindrical cells are known as epiblast (ectoblast) and the inner cubical cell layer is called the hypoblast (endoblast). The amniotic cavity (Figs. 4 - 6) has developed into the epiblast, in that fluids have accumulated between the THE VARIOUS PLACENTA TYPES The limited contact surface between mother and child, as occurs with a discoid placenta, is compensated by an intensive interdigitation between the two surfaces.In humans one finds the villus placenta that is constructed out of a highly complex system of interdigital folds (septa). The septa are thin, long and branched. The section comprised between two septa is called a cotyledon. DEVELOPMENT OF THE UMBILICAL CORD Development of the umbilical cord. The umbilical cord is formed when the body stalk and the ductus omphalo-entericus as well as the umbilical coelom are enveloped by the spreading amnion between the 4th and 8th week. Finally, when the membranes of the amniotic cavity come into contact with those of the chorionic cavity and the two extra THE CONDUCTION SYSTEM The first morphologically visible differentiation of the conduction system in human embryos is the sinu-atrial node 14.It is located in the wall of the right sinus horn near its opening in the right atrium, i.e., in the sulcus terminalis.THE CARDINAL SYSTEM
The cardinal system. The cardinal veins form as the basis for the intraembryonic venous part of the circulatory system. Various venous systems appear in various stages of the embryogenesis and partially disappear again. Very early in the development two paired systemsappear:
SWITCHING OVER AT BIRTH, CIRCULATION SYSTEM BEFORE / AFTER Circulation system after birth. Immediately after birth the newborn must begin to breathe regularly. The first breaths are difficult because the lungs are still filled with fluid (ca. 50 ml) and at birth the alveoli are collapsed. Half (50%) of this fluid is resorbed via the lymph vessels, a quarter is pressed out by the birth process (nottrue
QUIZ RESPIRATION TRACT In order to take the quiz, you must have the Flash 6 plugin installed on your computer (see "Downloads" in the Help menu) Quiz 01: Stages of lung development. Associated theory. Quiz 02: Bronchial tree at the end of the embryonic period. Associated theory. Quiz 03: How the blood circulation systems arise in the lungs. Associated theory. FETAL MEMBRANES, PLACENTA AND PREGNANCIES WITH TWINS For both twins, this kind of separation leads to a common placenta, a common chorion and a common amniotic cavity. As a rule, although only one placenta is present, the blood supply for the twins is well equalized. Nevertheless, sometimes the perfusion of one of the fetuses is favored which could partially explain why large size differencesoccur.
THE EXTERNAL GENITALIA, INDIFFERENT STAGE Indifferent stage. Quiz. Quiz 27. During the third week the cloacal membrane is formed and lies below the umbilical cord. In the fourth week, as the lower abdominal wall is being formed, the cloacal membrane is shifted caudally by immigrating mesenchyma coming from various sources. It is now delimited in front by a prominentmesenchymatous
ACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
THE EMBRYOBLAST
The embryoblast. On the 4th or 5th day 3 the embryoblast consists of a double-layered embryonic disk. The outer cylindrical cells are known as epiblast (ectoblast) and the inner cubical cell layer is called the hypoblast (endoblast). The amniotic cavity (Figs. 4 - 6) has developed into the epiblast, in that fluids have accumulated between the THE VARIOUS PLACENTA TYPES The limited contact surface between mother and child, as occurs with a discoid placenta, is compensated by an intensive interdigitation between the two surfaces.In humans one finds the villus placenta that is constructed out of a highly complex system of interdigital folds (septa). The septa are thin, long and branched. The section comprised between two septa is called a cotyledon. DEVELOPMENT OF THE UMBILICAL CORD Development of the umbilical cord. The umbilical cord is formed when the body stalk and the ductus omphalo-entericus as well as the umbilical coelom are enveloped by the spreading amnion between the 4th and 8th week. Finally, when the membranes of the amniotic cavity come into contact with those of the chorionic cavity and the two extra THE CONDUCTION SYSTEM The first morphologically visible differentiation of the conduction system in human embryos is the sinu-atrial node 14.It is located in the wall of the right sinus horn near its opening in the right atrium, i.e., in the sulcus terminalis.THE CARDINAL SYSTEM
The cardinal system. The cardinal veins form as the basis for the intraembryonic venous part of the circulatory system. Various venous systems appear in various stages of the embryogenesis and partially disappear again. Very early in the development two paired systemsappear:
SWITCHING OVER AT BIRTH, CIRCULATION SYSTEM BEFORE / AFTER Circulation system after birth. Immediately after birth the newborn must begin to breathe regularly. The first breaths are difficult because the lungs are still filled with fluid (ca. 50 ml) and at birth the alveoli are collapsed. Half (50%) of this fluid is resorbed via the lymph vessels, a quarter is pressed out by the birth process (nottrue
QUIZ RESPIRATION TRACT In order to take the quiz, you must have the Flash 6 plugin installed on your computer (see "Downloads" in the Help menu) Quiz 01: Stages of lung development. Associated theory. Quiz 02: Bronchial tree at the end of the embryonic period. Associated theory. Quiz 03: How the blood circulation systems arise in the lungs. Associated theory. FETAL MEMBRANES, PLACENTA AND PREGNANCIES WITH TWINS For both twins, this kind of separation leads to a common placenta, a common chorion and a common amniotic cavity. As a rule, although only one placenta is present, the blood supply for the twins is well equalized. Nevertheless, sometimes the perfusion of one of the fetuses is favored which could partially explain why large size differencesoccur.
THE EXTERNAL GENITALIA, INDIFFERENT STAGE Indifferent stage. Quiz. Quiz 27. During the third week the cloacal membrane is formed and lies below the umbilical cord. In the fourth week, as the lower abdominal wall is being formed, the cloacal membrane is shifted caudally by immigrating mesenchyma coming from various sources. It is now delimited in front by a prominentmesenchymatous
BRIEF SUMMARY EMBRYONIC DISK 7.5 Brief summary. This module describes the stages of the differentiation of the embryonic disk from the 2nd to the 4th week of its development. In the course of the 2nd week (7.1) the embryoblast differentiates itself into two germinal layers: the epiblast, out of which the tissue of the embryo as well as the amniotic epithelium willarise
LOWER URINARY SYSTEM In stage 13 13 the cloaca is the common end of the rectal tube and the urogenital tract. Towards the outside it is closed by the cloacal membrane. Between the 4th and 6th weeks the urorectal septum separates the cloaca into a primary urogenital sinus (ventrally) and the rectum (dorsally).. The bladder and the pelvic limb of the urethra arise from the primary urogenital sinus and the caudal THE POLARITY OF THE EMBRYO The polarity of the embryo is seen in the forming of embryonic and abembryonalic poles. This is obvious when observing a blastocyst where an inner cell mass ( ICM) has formed. This is concentrated at one pole in the interior of the hollow sphere and is made from blastomeres.Fig. 14 -
SWITCHING OVER AT BIRTH, CIRCULATION SYSTEM BEFORE / AFTER Circulation system after birth. Immediately after birth the newborn must begin to breathe regularly. The first breaths are difficult because the lungs are still filled with fluid (ca. 50 ml) and at birth the alveoli are collapsed. Half (50%) of this fluid is resorbed via the lymph vessels, a quarter is pressed out by the birth process (nottrue
ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantationBRIEF SUMMARY
3.7 Brief summary. Gametes and their predecessor cells (the primordial germ cells) are differentiated from other somatic cells very early, and emigrate from the ectoderm (third week) via the extraembryonic endoderm (fifth week) into the primordium of the future gonads, the gonadal ridge. There, through an interaction with the coelomic DEVELOPMENT OF THE PLACENTAL VILLI A web-based training in medical embryology. From this time on gases, nutrients, and waste products that diffuse through the maternal and fetal blood must pass through a total of four layers: . Capillary endothelium of the villus Loose connective tissue that surrounds theendothelium
DEVELOPMENT OF THE PLACENTAL VILLI Connections between maternal and fetal tissues. Maternal and fetal tissues form two units that are closely bound together at the placental level. The fetal part of the placenta is made up of the chorionic plate with its placental villi, the cytotrophoblast layer and the intervillous spaces. The chorionic plate (great part of theplacenta on the
PANCREAS; DORSAL PANCREAS; VENTRAL PANCREAS The dorsal pancreas anlage expands relatively rapidly into the mesoduodenum below the large curvature of the stomach. It comes to lie with its tail-like part (cauda) near the spleen.Its outflow passage, which emerges from its head, normally fuses with the outflow passage of the ventral pancreas anlage to become the major pancreatic duct.These join with the bile duct and discharge into the LOWER URINARY SYSTEM The urethra forms itself from the lower part of the urogenital sinus (UGS). In a man the prostate and membranous part of the urethra arise from the pelvic part of the UGS while the spongy urethra comes from the phallic part (urethral plate).; In a woman the whole urethra and part of the vagina arise from the pelvic part of the UGS while the phallic part (urethral plate) forms the vestibule andACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
THE VARIOUS PLACENTA TYPES The limited contact surface between mother and child, as occurs with a discoid placenta, is compensated by an intensive interdigitation between the two surfaces.In humans one finds the villus placenta that is constructed out of a highly complex system of interdigital folds (septa). The septa are thin, long and branched. The section comprised between two septa is called a cotyledon.THE EMBRYOBLAST
The embryoblast. On the 4th or 5th day 3 the embryoblast consists of a double-layered embryonic disk. The outer cylindrical cells are known as epiblast (ectoblast) and the inner cubical cell layer is called the hypoblast (endoblast). The amniotic cavity (Figs. 4 - 6) has developed into the epiblast, in that fluids have accumulated between theCHANGES AT BIRTH
Changes at birth. With birth, a change from parallel flow through the heart to a serial one gradually takes place. The following changes must occur: The gas exchange takes place in the baby's lungs. By cutting the umbilical cord, the placental circulation system is switched off. The fetal heart shunts become closed. FETOPATHIES, OVERVIEW Fetopathies are fetal damages occurring after embryogenesis has ended and up to the time of birth. Compared with the vulnerability during organogenesis in the embryonic phase the sensibility to substances that can cause abnormalities is less pronounced in the fetal period. Such substances are also termed "teratogenic" and the research in this QUIZ RESPIRATION TRACT In order to take the quiz, you must have the Flash 6 plugin installed on your computer (see "Downloads" in the Help menu) Quiz 01: Stages of lung development. Associated theory. Quiz 02: Bronchial tree at the end of the embryonic period. Associated theory. Quiz 03: How the blood circulation systems arise in the lungs. Associated theory. THE CONDUCTION SYSTEM The first morphologically visible differentiation of the conduction system in human embryos is the sinu-atrial node 14.It is located in the wall of the right sinus horn near its opening in the right atrium, i.e., in the sulcus terminalis. SWITCHING OVER AT BIRTH, CIRCULATION SYSTEM BEFORE / AFTER Circulation system after birth. Immediately after birth the newborn must begin to breathe regularly. The first breaths are difficult because the lungs are still filled with fluid (ca. 50 ml) and at birth the alveoli are collapsed. Half (50%) of this fluid is resorbed via the lymph vessels, a quarter is pressed out by the birth process (nottrue
DESCENT OF THE TESTES Descent of the testes. Between the 3rd month of pregnancy and its end the testes become transferred from the lumbar area (ventro-medial to the mesonephros) into the future scrotum. This transfer is due to a combination of growth processes and hormonal influences ( 7 ). The gubernaculum testis also plays a decisive role in this phenomenon. FETAL MEMBRANES, PLACENTA AND PREGNANCIES WITH TWINS For both twins, this kind of separation leads to a common placenta, a common chorion and a common amniotic cavity. As a rule, although only one placenta is present, the blood supply for the twins is well equalized. Nevertheless, sometimes the perfusion of one of the fetuses is favored which could partially explain why large size differencesoccur.
ACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
THE VARIOUS PLACENTA TYPES The limited contact surface between mother and child, as occurs with a discoid placenta, is compensated by an intensive interdigitation between the two surfaces.In humans one finds the villus placenta that is constructed out of a highly complex system of interdigital folds (septa). The septa are thin, long and branched. The section comprised between two septa is called a cotyledon.THE EMBRYOBLAST
The embryoblast. On the 4th or 5th day 3 the embryoblast consists of a double-layered embryonic disk. The outer cylindrical cells are known as epiblast (ectoblast) and the inner cubical cell layer is called the hypoblast (endoblast). The amniotic cavity (Figs. 4 - 6) has developed into the epiblast, in that fluids have accumulated between theCHANGES AT BIRTH
Changes at birth. With birth, a change from parallel flow through the heart to a serial one gradually takes place. The following changes must occur: The gas exchange takes place in the baby's lungs. By cutting the umbilical cord, the placental circulation system is switched off. The fetal heart shunts become closed. FETOPATHIES, OVERVIEW Fetopathies are fetal damages occurring after embryogenesis has ended and up to the time of birth. Compared with the vulnerability during organogenesis in the embryonic phase the sensibility to substances that can cause abnormalities is less pronounced in the fetal period. Such substances are also termed "teratogenic" and the research in this QUIZ RESPIRATION TRACT In order to take the quiz, you must have the Flash 6 plugin installed on your computer (see "Downloads" in the Help menu) Quiz 01: Stages of lung development. Associated theory. Quiz 02: Bronchial tree at the end of the embryonic period. Associated theory. Quiz 03: How the blood circulation systems arise in the lungs. Associated theory. THE CONDUCTION SYSTEM The first morphologically visible differentiation of the conduction system in human embryos is the sinu-atrial node 14.It is located in the wall of the right sinus horn near its opening in the right atrium, i.e., in the sulcus terminalis. SWITCHING OVER AT BIRTH, CIRCULATION SYSTEM BEFORE / AFTER Circulation system after birth. Immediately after birth the newborn must begin to breathe regularly. The first breaths are difficult because the lungs are still filled with fluid (ca. 50 ml) and at birth the alveoli are collapsed. Half (50%) of this fluid is resorbed via the lymph vessels, a quarter is pressed out by the birth process (nottrue
DESCENT OF THE TESTES Descent of the testes. Between the 3rd month of pregnancy and its end the testes become transferred from the lumbar area (ventro-medial to the mesonephros) into the future scrotum. This transfer is due to a combination of growth processes and hormonal influences ( 7 ). The gubernaculum testis also plays a decisive role in this phenomenon. FETAL MEMBRANES, PLACENTA AND PREGNANCIES WITH TWINS For both twins, this kind of separation leads to a common placenta, a common chorion and a common amniotic cavity. As a rule, although only one placenta is present, the blood supply for the twins is well equalized. Nevertheless, sometimes the perfusion of one of the fetuses is favored which could partially explain why large size differencesoccur.
BRIEF SUMMARY EMBRYONIC DISK 7.5 Brief summary. This module describes the stages of the differentiation of the embryonic disk from the 2nd to the 4th week of its development. In the course of the 2nd week (7.1) the embryoblast differentiates itself into two germinal layers: the epiblast, out of which the tissue of the embryo as well as the amniotic epithelium willarise
THE CARDINAL SYSTEM
The cardinal system. The cardinal veins form as the basis for the intraembryonic venous part of the circulatory system. Various venous systems appear in various stages of the embryogenesis and partially disappear again. Very early in the development two paired systemsappear:
LOWER URINARY SYSTEM In stage 13 13 the cloaca is the common end of the rectal tube and the urogenital tract. Towards the outside it is closed by the cloacal membrane. Between the 4th and 6th weeks the urorectal septum separates the cloaca into a primary urogenital sinus (ventrally) and the rectum (dorsally).. The bladder and the pelvic limb of the urethra arise from the primary urogenital sinus and the caudal DEVELOPMENT OF THE PLACENTAL VILLI A web-based training in medical embryology. From this time on gases, nutrients, and waste products that diffuse through the maternal and fetal blood must pass through a total of four layers: . Capillary endothelium of the villus Loose connective tissue that surrounds theendothelium
ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantation DEVELOPMENT OF THE PLACENTAL VILLI Connections between maternal and fetal tissues. Maternal and fetal tissues form two units that are closely bound together at the placental level. The fetal part of the placenta is made up of the chorionic plate with its placental villi, the cytotrophoblast layer and the intervillous spaces. The chorionic plate (great part of theplacenta on the
DISPLACEMENT OF THE OVARIES A web-based training in medical embryology. Through atrophy of the mesonephros the upper gubernaculum connects the ovary directly with the upper rear body wall and becomes designated as the suspensory ligament of ovary. The lower gubernaculum has its origin in the bottom side of the ovary and forms the ovarian ligament and, further down, the round ligament of uterus that reaches the genital PANCREAS; DORSAL PANCREAS; VENTRAL PANCREAS The ventral pancreas anlage arises somewhat later (stage 13-14, ca. 32-33 days, 13) as a budding from the bile duct.Due to the 90 degree rotation of the stomach and the lengthening of the duodenal loop the bile duct with the gall bladder and the ventral pancreas are moved towards the rear, thus rotating around the duodenum and reaches then a position ventral to the dorsal pancreas. SPERMATOZOA MATURATION STEPS The spermatozoa have to go through several temporal maturation steps in a series of different locations in order to be capable of penetrating into the oocyte. While the oocyte's maturation steps involve the storing of yolk and the process of meiosis, functional maturation steps are required with the spermatozoa, which mainly involve their motile abilities along with their ability to penetrate THE PATH OF THE SPERM CELLS TO THE OOCYTE The path that the sperm cells must travel from the portio to their meeting with the oocyte in the ampullary part of the fallopian tube is 13-15 cm long. Along this stretch, sperm cells go through a further maturation process, the so-called capacitation. The mechanisms that guide the sperm cells to the oocyte have not been researched in allACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
HOME
HUMAN EMBRYOLOGY. Embryogenesis. Organogenesis. Online course in embryology for medicine students. developed by the universities of Fribourg, Lausanne and Bern (Switzerland) with the support of the Swiss Virtual Campus. ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantation POUMON, MODIFICATION À LA NAISSANCE, SITUATIONTRANSLATE THIS PAGE Situation de la circulation après la naissance. Le nouveau-né doit commencer à respirer immédiatement après la naissance. Les premiers cycles respiratoires sont pénibles, les poumons étant encore remplis de liquide (env. 50ml) et les alvéoles collabées au moment de la naissance. La moitié (50 %) du liquide est résorbé par les CIRCULATION EMBRYONNAIRE ET FOETALE La circulation foetale. En raison du flux sanguin cardiaque parallèle et des deux shunts précités, la circulation suivante va s'établir au niveau foetal. Le sang riche en nutriments et en oxygène en provenance du placenta, atteint via la veine ombilicale le foie, qu'il traverse en partie ou qu'il contourne via le conduit veineux etatteint
MÉTHODES CONTRACEPTIVES EMPÊCHANT L'IMPLANTATIONTRANSLATE THIS PAGE Les méthodes contraceptives concernent l'ensemble des dispositions permettant d'éviter qu'un rapport sexuel ne soit fécondant. Il existe des méthodes archaïques et des méthodes sophistiquées, notamment hormonales présentant un taux d'efficacité optimal lorsqu'elles sont appliquées correctement. Empêcher l'implantationde l'oeuf
RÔLE ET ANATOMIE FONCTIONNELS DE L'ENDOMÈTRETRANSLATE THIS PAGE L'utérus à pour fonction principale de recevoir et d'héberger l'embryon, puis le foetus, au cours de la grossesse.Il s'agit d'un organe musculaire piriforme et creux, constitué d'une paroi formée de trois couches: une tunique séreuse externe, le périmètre, une tunique musculaire épaisse, le myomètre, et un revêtement muqueux interne, l'endomètre. LA PÉNÉTRATION DU SPERMATOZOÏDE DANS L'OVOCYTETRANSLATE THIS PAGE La pénétration du spermatozoïde dans l'ovule (imprégnation) Après l'arrimage du spermatozoïde à l'ovule, les deux membranes fusionnent. Cela permet aux structures qui se trouvent à l'intérieur du spermatozoïde de passer dans le cytoplasme de l'ovule. On appelle ce processus imprégnation de l'ovule. PATHOLOGIES DE LA DIFFÉRENCIATION SEXUELLE D'ORIGINETRANSLATE THISPAGE
L'hermaphrodisme vrai est très rare.Il s'agit d'individus possédant à la fois un tissu testiculaire et un tissu ovarien.. Etiologie: Le caryotype des hermaphrodites résulte d'altérations au niveau des gonosomes (chromosomes sexuels) pouvant donner des mosaïques (environ 30%) à deux populations cellulaires résultant de la fusion de deux zygotes de sexe différent. THE PATH OF THE SPERM CELLS TO THE OOCYTE The path that the sperm cells must travel from the portio to their meeting with the oocyte in the ampullary part of the fallopian tube is 13-15 cm long. Along this stretch, sperm cells go through a further maturation process, the so-called capacitation. The mechanisms that guide the sperm cells to the oocyte have not been researched in allACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
HOME
HUMAN EMBRYOLOGY. Embryogenesis. Organogenesis. Online course in embryology for medicine students. developed by the universities of Fribourg, Lausanne and Bern (Switzerland) with the support of the Swiss Virtual Campus. ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantation POUMON, MODIFICATION À LA NAISSANCE, SITUATIONTRANSLATE THIS PAGE Situation de la circulation après la naissance. Le nouveau-né doit commencer à respirer immédiatement après la naissance. Les premiers cycles respiratoires sont pénibles, les poumons étant encore remplis de liquide (env. 50ml) et les alvéoles collabées au moment de la naissance. La moitié (50 %) du liquide est résorbé par les CIRCULATION EMBRYONNAIRE ET FOETALE La circulation foetale. En raison du flux sanguin cardiaque parallèle et des deux shunts précités, la circulation suivante va s'établir au niveau foetal. Le sang riche en nutriments et en oxygène en provenance du placenta, atteint via la veine ombilicale le foie, qu'il traverse en partie ou qu'il contourne via le conduit veineux etatteint
MÉTHODES CONTRACEPTIVES EMPÊCHANT L'IMPLANTATIONTRANSLATE THIS PAGE Les méthodes contraceptives concernent l'ensemble des dispositions permettant d'éviter qu'un rapport sexuel ne soit fécondant. Il existe des méthodes archaïques et des méthodes sophistiquées, notamment hormonales présentant un taux d'efficacité optimal lorsqu'elles sont appliquées correctement. Empêcher l'implantationde l'oeuf
RÔLE ET ANATOMIE FONCTIONNELS DE L'ENDOMÈTRETRANSLATE THIS PAGE L'utérus à pour fonction principale de recevoir et d'héberger l'embryon, puis le foetus, au cours de la grossesse.Il s'agit d'un organe musculaire piriforme et creux, constitué d'une paroi formée de trois couches: une tunique séreuse externe, le périmètre, une tunique musculaire épaisse, le myomètre, et un revêtement muqueux interne, l'endomètre. LA PÉNÉTRATION DU SPERMATOZOÏDE DANS L'OVOCYTETRANSLATE THIS PAGE La pénétration du spermatozoïde dans l'ovule (imprégnation) Après l'arrimage du spermatozoïde à l'ovule, les deux membranes fusionnent. Cela permet aux structures qui se trouvent à l'intérieur du spermatozoïde de passer dans le cytoplasme de l'ovule. On appelle ce processus imprégnation de l'ovule. PATHOLOGIES DE LA DIFFÉRENCIATION SEXUELLE D'ORIGINETRANSLATE THISPAGE
L'hermaphrodisme vrai est très rare.Il s'agit d'individus possédant à la fois un tissu testiculaire et un tissu ovarien.. Etiologie: Le caryotype des hermaphrodites résulte d'altérations au niveau des gonosomes (chromosomes sexuels) pouvant donner des mosaïques (environ 30%) à deux populations cellulaires résultant de la fusion de deux zygotes de sexe différent. THE PATH OF THE SPERM CELLS TO THE OOCYTE The path that the sperm cells must travel from the portio to their meeting with the oocyte in the ampullary part of the fallopian tube is 13-15 cm long. Along this stretch, sperm cells go through a further maturation process, the so-called capacitation. The mechanisms that guide the sperm cells to the oocyte have not been researched in allHOME
HUMAN EMBRYOLOGY. Embryogenesis. Organogenesis. Online course in embryology for medicine students. developed by the universities of Fribourg, Lausanne and Bern (Switzerland) with the support of the Swiss Virtual Campus. MODULE - EMBRYOLOGY.CHTRANSLATE THIS PAGE A web-based training in medical embryology. Pour accéder à un module et à sa liste des chapitres cliquez sur sa zone. ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantation PÉRIODE EMBRYONNAIRE 8.4 Evènements clés de la 3e à la 8e semaine du développement. Introduction et rappel de la troisième semaine (stade 6-7; env. 17-19 jours) Quatrième semaine (stade 8-10; env. 23-28 jours) Cinquième semaine (stade 11-14; env. 29-33 jours) Développement des arcs branchiaux. Sixième semaine (stade 15-17; env. 36-41 jours) LES VALVES SEMI-LUNAIRES Les valves semi-lunaires. Comme nous l'avons décrit lors de l'étude du cloisonnement de la voie efférente, la courbure entre le cône et le tronc revêt une signification particulière. C'est à ce niveau que se développement les valves semi-lunaires. Ce sont essentiellement les bourrelets mésenchymateux, induits parl'immigration des
10.3 LA CIRCULATION PLACENTAIRE La circulation placentaire met en commun deux circulations, foetale et maternelle, situées de chaque côté du placenta.Le débit en est élevé: 500ml/min (80% du débit utérin) et est influencé par divers facteurs tels que notamment la volémie, la tension artérielle, les contractions utérines, le tabagisme, les médicaments et les hormones. PREMIERS SIGNES DU DÉVELOPPEMENT CARDIAQUETRANSLATE THIS PAGE Premiers signes du développement cardiaque. L'aire cardiogénique est une accumulation de cellules mésodermiques dans la partie céphalique de l'embryon. Observez dans le schéma interactif, la modification de la position de la cavité péritonéale en rapport avec l'aire cardiogénique, lors de la flexion de la partie crâniale del'embryon.
LA DÉTERMINATION DU SEXE, EBAUCHE DES GONADES …TRANSLATE THIS PAGE La clé pour la différenciation sexuelle se trouve sur le chromosome Y plus spécifiquement sur le gène SRY (sex determining region of the Y chromosome), qui induit la différenciation sexuelle masculine. L'expression du gène SRY correspond à la période de la détermination sexuelle, il est exprimé dans les cellules somatiques des crêtes génitales masculines LES SPERMATOZOÏDES PARVIENNENT À L'OVULE Le fait que la liaison à la zone pellucide est spécifique de l'espèce nous laisse penser que c'est une étape déterminante dans la cascade de la fécondation; en revanche, la liaison à l'ovule qui à lieu ensuite n'est pas spécifique de l'espèce. Lorsque la réaction acrosomique s'est achevée, le spermatozoïde n'est alors recouvert à l'avant plus que par ce qui était la membrane SEXE FÉMININ: DIFFÉRENCIATION DES VOIES GÉNITALESTRANSLATE THISPAGE
Sexe féminin: différenciation des voies génitales. Durant la 7e semaine les voies génitales féminines se différencient. En l'absence d' AMH, les canaux mésonéphrotiques régressent et les conduits paramésonéphrotiques ou canaux de Müller donneront naissance aux futures trompes utérines, à l'utérus et à la partiesupérieure du
ACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
HOME
HUMAN EMBRYOLOGY. Embryogenesis. Organogenesis. Online course in embryology for medicine students. developed by the universities of Fribourg, Lausanne and Bern (Switzerland) with the support of the Swiss Virtual Campus. ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantation POUMON, MODIFICATION À LA NAISSANCE, SITUATIONTRANSLATE THIS PAGE Situation de la circulation après la naissance. Le nouveau-né doit commencer à respirer immédiatement après la naissance. Les premiers cycles respiratoires sont pénibles, les poumons étant encore remplis de liquide (env. 50ml) et les alvéoles collabées au moment de la naissance. La moitié (50 %) du liquide est résorbé par les CIRCULATION EMBRYONNAIRE ET FOETALE La circulation foetale. En raison du flux sanguin cardiaque parallèle et des deux shunts précités, la circulation suivante va s'établir au niveau foetal. Le sang riche en nutriments et en oxygène en provenance du placenta, atteint via la veine ombilicale le foie, qu'il traverse en partie ou qu'il contourne via le conduit veineux etatteint
MÉTHODES CONTRACEPTIVES EMPÊCHANT L'IMPLANTATIONTRANSLATE THIS PAGE Les méthodes contraceptives concernent l'ensemble des dispositions permettant d'éviter qu'un rapport sexuel ne soit fécondant. Il existe des méthodes archaïques et des méthodes sophistiquées, notamment hormonales présentant un taux d'efficacité optimal lorsqu'elles sont appliquées correctement. Empêcher l'implantationde l'oeuf
RÔLE ET ANATOMIE FONCTIONNELS DE L'ENDOMÈTRETRANSLATE THIS PAGE L'utérus à pour fonction principale de recevoir et d'héberger l'embryon, puis le foetus, au cours de la grossesse.Il s'agit d'un organe musculaire piriforme et creux, constitué d'une paroi formée de trois couches: une tunique séreuse externe, le périmètre, une tunique musculaire épaisse, le myomètre, et un revêtement muqueux interne, l'endomètre. LA PÉNÉTRATION DU SPERMATOZOÏDE DANS L'OVOCYTETRANSLATE THIS PAGE La pénétration du spermatozoïde dans l'ovule (imprégnation) Après l'arrimage du spermatozoïde à l'ovule, les deux membranes fusionnent. Cela permet aux structures qui se trouvent à l'intérieur du spermatozoïde de passer dans le cytoplasme de l'ovule. On appelle ce processus imprégnation de l'ovule. PATHOLOGIES DE LA DIFFÉRENCIATION SEXUELLE D'ORIGINETRANSLATE THISPAGE
L'hermaphrodisme vrai est très rare.Il s'agit d'individus possédant à la fois un tissu testiculaire et un tissu ovarien.. Etiologie: Le caryotype des hermaphrodites résulte d'altérations au niveau des gonosomes (chromosomes sexuels) pouvant donner des mosaïques (environ 30%) à deux populations cellulaires résultant de la fusion de deux zygotes de sexe différent. THE PATH OF THE SPERM CELLS TO THE OOCYTE The path that the sperm cells must travel from the portio to their meeting with the oocyte in the ampullary part of the fallopian tube is 13-15 cm long. Along this stretch, sperm cells go through a further maturation process, the so-called capacitation. The mechanisms that guide the sperm cells to the oocyte have not been researched in allACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
HOME
HUMAN EMBRYOLOGY. Embryogenesis. Organogenesis. Online course in embryology for medicine students. developed by the universities of Fribourg, Lausanne and Bern (Switzerland) with the support of the Swiss Virtual Campus. ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantation POUMON, MODIFICATION À LA NAISSANCE, SITUATIONTRANSLATE THIS PAGE Situation de la circulation après la naissance. Le nouveau-né doit commencer à respirer immédiatement après la naissance. Les premiers cycles respiratoires sont pénibles, les poumons étant encore remplis de liquide (env. 50ml) et les alvéoles collabées au moment de la naissance. La moitié (50 %) du liquide est résorbé par les CIRCULATION EMBRYONNAIRE ET FOETALE La circulation foetale. En raison du flux sanguin cardiaque parallèle et des deux shunts précités, la circulation suivante va s'établir au niveau foetal. Le sang riche en nutriments et en oxygène en provenance du placenta, atteint via la veine ombilicale le foie, qu'il traverse en partie ou qu'il contourne via le conduit veineux etatteint
MÉTHODES CONTRACEPTIVES EMPÊCHANT L'IMPLANTATIONTRANSLATE THIS PAGE Les méthodes contraceptives concernent l'ensemble des dispositions permettant d'éviter qu'un rapport sexuel ne soit fécondant. Il existe des méthodes archaïques et des méthodes sophistiquées, notamment hormonales présentant un taux d'efficacité optimal lorsqu'elles sont appliquées correctement. Empêcher l'implantationde l'oeuf
RÔLE ET ANATOMIE FONCTIONNELS DE L'ENDOMÈTRETRANSLATE THIS PAGE L'utérus à pour fonction principale de recevoir et d'héberger l'embryon, puis le foetus, au cours de la grossesse.Il s'agit d'un organe musculaire piriforme et creux, constitué d'une paroi formée de trois couches: une tunique séreuse externe, le périmètre, une tunique musculaire épaisse, le myomètre, et un revêtement muqueux interne, l'endomètre. LA PÉNÉTRATION DU SPERMATOZOÏDE DANS L'OVOCYTETRANSLATE THIS PAGE La pénétration du spermatozoïde dans l'ovule (imprégnation) Après l'arrimage du spermatozoïde à l'ovule, les deux membranes fusionnent. Cela permet aux structures qui se trouvent à l'intérieur du spermatozoïde de passer dans le cytoplasme de l'ovule. On appelle ce processus imprégnation de l'ovule. PATHOLOGIES DE LA DIFFÉRENCIATION SEXUELLE D'ORIGINETRANSLATE THISPAGE
L'hermaphrodisme vrai est très rare.Il s'agit d'individus possédant à la fois un tissu testiculaire et un tissu ovarien.. Etiologie: Le caryotype des hermaphrodites résulte d'altérations au niveau des gonosomes (chromosomes sexuels) pouvant donner des mosaïques (environ 30%) à deux populations cellulaires résultant de la fusion de deux zygotes de sexe différent. THE PATH OF THE SPERM CELLS TO THE OOCYTE The path that the sperm cells must travel from the portio to their meeting with the oocyte in the ampullary part of the fallopian tube is 13-15 cm long. Along this stretch, sperm cells go through a further maturation process, the so-called capacitation. The mechanisms that guide the sperm cells to the oocyte have not been researched in allHOME
HUMAN EMBRYOLOGY. Embryogenesis. Organogenesis. Online course in embryology for medicine students. developed by the universities of Fribourg, Lausanne and Bern (Switzerland) with the support of the Swiss Virtual Campus. MODULE - EMBRYOLOGY.CHTRANSLATE THIS PAGE A web-based training in medical embryology. Pour accéder à un module et à sa liste des chapitres cliquez sur sa zone. ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantation PÉRIODE EMBRYONNAIRE 8.4 Evènements clés de la 3e à la 8e semaine du développement. Introduction et rappel de la troisième semaine (stade 6-7; env. 17-19 jours) Quatrième semaine (stade 8-10; env. 23-28 jours) Cinquième semaine (stade 11-14; env. 29-33 jours) Développement des arcs branchiaux. Sixième semaine (stade 15-17; env. 36-41 jours) LES VALVES SEMI-LUNAIRES Les valves semi-lunaires. Comme nous l'avons décrit lors de l'étude du cloisonnement de la voie efférente, la courbure entre le cône et le tronc revêt une signification particulière. C'est à ce niveau que se développement les valves semi-lunaires. Ce sont essentiellement les bourrelets mésenchymateux, induits parl'immigration des
10.3 LA CIRCULATION PLACENTAIRE La circulation placentaire met en commun deux circulations, foetale et maternelle, situées de chaque côté du placenta.Le débit en est élevé: 500ml/min (80% du débit utérin) et est influencé par divers facteurs tels que notamment la volémie, la tension artérielle, les contractions utérines, le tabagisme, les médicaments et les hormones. PREMIERS SIGNES DU DÉVELOPPEMENT CARDIAQUETRANSLATE THIS PAGE Premiers signes du développement cardiaque. L'aire cardiogénique est une accumulation de cellules mésodermiques dans la partie céphalique de l'embryon. Observez dans le schéma interactif, la modification de la position de la cavité péritonéale en rapport avec l'aire cardiogénique, lors de la flexion de la partie crâniale del'embryon.
LA DÉTERMINATION DU SEXE, EBAUCHE DES GONADES …TRANSLATE THIS PAGE La clé pour la différenciation sexuelle se trouve sur le chromosome Y plus spécifiquement sur le gène SRY (sex determining region of the Y chromosome), qui induit la différenciation sexuelle masculine. L'expression du gène SRY correspond à la période de la détermination sexuelle, il est exprimé dans les cellules somatiques des crêtes génitales masculines LES SPERMATOZOÏDES PARVIENNENT À L'OVULE Le fait que la liaison à la zone pellucide est spécifique de l'espèce nous laisse penser que c'est une étape déterminante dans la cascade de la fécondation; en revanche, la liaison à l'ovule qui à lieu ensuite n'est pas spécifique de l'espèce. Lorsque la réaction acrosomique s'est achevée, le spermatozoïde n'est alors recouvert à l'avant plus que par ce qui était la membrane SEXE FÉMININ: DIFFÉRENCIATION DES VOIES GÉNITALESTRANSLATE THISPAGE
Sexe féminin: différenciation des voies génitales. Durant la 7e semaine les voies génitales féminines se différencient. En l'absence d' AMH, les canaux mésonéphrotiques régressent et les conduits paramésonéphrotiques ou canaux de Müller donneront naissance aux futures trompes utérines, à l'utérus et à la partiesupérieure du
ACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
HOME
HUMAN EMBRYOLOGY. Embryogenesis. Organogenesis. Online course in embryology for medicine students. developed by the universities of Fribourg, Lausanne and Bern (Switzerland) with the support of the Swiss Virtual Campus. THE VARIOUS PLACENTA TYPES The limited contact surface between mother and child, as occurs with a discoid placenta, is compensated by an intensive interdigitation between the two surfaces.In humans one finds the villus placenta that is constructed out of a highly complex system of interdigital folds (septa). The septa are thin, long and branched. The section comprised between two septa is called a cotyledon.CHANGES AT BIRTH
Changes at birth. With birth, a change from parallel flow through the heart to a serial one gradually takes place. The following changes must occur: The gas exchange takes place in the baby's lungs. By cutting the umbilical cord, the placental circulation system is switched off. The fetal heart shunts become closed. THE CONDUCTION SYSTEM The first morphologically visible differentiation of the conduction system in human embryos is the sinu-atrial node 14.It is located in the wall of the right sinus horn near its opening in the right atrium, i.e., in the sulcus terminalis. QUIZ RESPIRATION TRACT In order to take the quiz, you must have the Flash 6 plugin installed on your computer (see "Downloads" in the Help menu) Quiz 01: Stages of lung development. Associated theory. Quiz 02: Bronchial tree at the end of the embryonic period. Associated theory. Quiz 03: How the blood circulation systems arise in the lungs. Associated theory. DEVELOPMENT OF THE UMBILICAL CORD Development of the umbilical cord. The umbilical cord is formed when the body stalk and the ductus omphalo-entericus as well as the umbilical coelom are enveloped by the spreading amnion between the 4th and 8th week. Finally, when the membranes of the amniotic cavity come into contact with those of the chorionic cavity and the two extra DESCENT OF THE TESTES Descent of the testes. Between the 3rd month of pregnancy and its end the testes become transferred from the lumbar area (ventro-medial to the mesonephros) into the future scrotum. This transfer is due to a combination of growth processes and hormonal influences ( 7 ). The gubernaculum testis also plays a decisive role in this phenomenon. FETAL MEMBRANES, PLACENTA AND PREGNANCIES WITH TWINS For both twins, this kind of separation leads to a common placenta, a common chorion and a common amniotic cavity. As a rule, although only one placenta is present, the blood supply for the twins is well equalized. Nevertheless, sometimes the perfusion of one of the fetuses is favored which could partially explain why large size differencesoccur.
THE EXTERNAL GENITALIA, INDIFFERENT STAGE Indifferent stage. Quiz. Quiz 27. During the third week the cloacal membrane is formed and lies below the umbilical cord. In the fourth week, as the lower abdominal wall is being formed, the cloacal membrane is shifted caudally by immigrating mesenchyma coming from various sources. It is now delimited in front by a prominentmesenchymatous
ACCUEIL/HOME
Accueil/Home. EMBRYOLOGIE HUMAINE. Embryogénèse. Organogénèse. Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine.
HOME
HUMAN EMBRYOLOGY. Embryogenesis. Organogenesis. Online course in embryology for medicine students. developed by the universities of Fribourg, Lausanne and Bern (Switzerland) with the support of the Swiss Virtual Campus. THE VARIOUS PLACENTA TYPES The limited contact surface between mother and child, as occurs with a discoid placenta, is compensated by an intensive interdigitation between the two surfaces.In humans one finds the villus placenta that is constructed out of a highly complex system of interdigital folds (septa). The septa are thin, long and branched. The section comprised between two septa is called a cotyledon.CHANGES AT BIRTH
Changes at birth. With birth, a change from parallel flow through the heart to a serial one gradually takes place. The following changes must occur: The gas exchange takes place in the baby's lungs. By cutting the umbilical cord, the placental circulation system is switched off. The fetal heart shunts become closed. THE CONDUCTION SYSTEM The first morphologically visible differentiation of the conduction system in human embryos is the sinu-atrial node 14.It is located in the wall of the right sinus horn near its opening in the right atrium, i.e., in the sulcus terminalis. QUIZ RESPIRATION TRACT In order to take the quiz, you must have the Flash 6 plugin installed on your computer (see "Downloads" in the Help menu) Quiz 01: Stages of lung development. Associated theory. Quiz 02: Bronchial tree at the end of the embryonic period. Associated theory. Quiz 03: How the blood circulation systems arise in the lungs. Associated theory. DEVELOPMENT OF THE UMBILICAL CORD Development of the umbilical cord. The umbilical cord is formed when the body stalk and the ductus omphalo-entericus as well as the umbilical coelom are enveloped by the spreading amnion between the 4th and 8th week. Finally, when the membranes of the amniotic cavity come into contact with those of the chorionic cavity and the two extra DESCENT OF THE TESTES Descent of the testes. Between the 3rd month of pregnancy and its end the testes become transferred from the lumbar area (ventro-medial to the mesonephros) into the future scrotum. This transfer is due to a combination of growth processes and hormonal influences ( 7 ). The gubernaculum testis also plays a decisive role in this phenomenon. FETAL MEMBRANES, PLACENTA AND PREGNANCIES WITH TWINS For both twins, this kind of separation leads to a common placenta, a common chorion and a common amniotic cavity. As a rule, although only one placenta is present, the blood supply for the twins is well equalized. Nevertheless, sometimes the perfusion of one of the fetuses is favored which could partially explain why large size differencesoccur.
THE EXTERNAL GENITALIA, INDIFFERENT STAGE Indifferent stage. Quiz. Quiz 27. During the third week the cloacal membrane is formed and lies below the umbilical cord. In the fourth week, as the lower abdominal wall is being formed, the cloacal membrane is shifted caudally by immigrating mesenchyma coming from various sources. It is now delimited in front by a prominentmesenchymatous
HOME
HUMAN EMBRYOLOGY. Embryogenesis. Organogenesis. Online course in embryology for medicine students. developed by the universities of Fribourg, Lausanne and Bern (Switzerland) with the support of the Swiss Virtual Campus. CARNEGIE - STAGE 1-23 - EMBRYOLOGY.CH Separation of the blastomeres (totipotent) Morula stage Compaction (8 to 16 cells) The polarization of the blastomeres is slowly visible. ROLE AND FUNCTIONAL ANATOMY OF THE ENDOMETRIUM The main functions of the uterus are receiving the embryo, sheltering the fetus during pregnancy and delivering the newborn at term. The uterus is a pear-shaped, muscular, hollow organ with a triple-layered wall: an outer tunica serosa, the perimetrium, a thick tunica muscularis, the myometrium, and an inner tunica mucosa, the endometrium.The endometrium is the layer in which the implantation LOWER URINARY SYSTEM In stage 13 13 the cloaca is the common end of the rectal tube and the urogenital tract. Towards the outside it is closed by the cloacal membrane. Between the 4th and 6th weeks the urorectal septum separates the cloaca into a primary urogenital sinus (ventrally) and the rectum (dorsally).. The bladder and the pelvic limb of the urethra arise from the primary urogenital sinus and the caudal SWITCHING OVER AT BIRTH, CIRCULATION SYSTEM BEFORE / AFTER Circulation system after birth. Immediately after birth the newborn must begin to breathe regularly. The first breaths are difficult because the lungs are still filled with fluid (ca. 50 ml) and at birth the alveoli are collapsed. Half (50%) of this fluid is resorbed via the lymph vessels, a quarter is pressed out by the birth process (nottrue
DEVELOPMENT OF THE PERICARDIUM Development of the pericardium. In the early part of stage 9 (ca. 25th day) 9 the embryo is shaped like a foot sole and consists of ectoderm, mesoderm and endoderm cell layers. In the extraembryonic region the lateral plate mesoderm becomes split. The visceral layer, covering the umbilical vesicle, forms the splanchnopleura together with the DEVELOPMENT OF THE PLACENTAL VILLI Connections between maternal and fetal tissues. Maternal and fetal tissues form two units that are closely bound together at the placental level. The fetal part of the placenta is made up of the chorionic plate with its placental villi, the cytotrophoblast layer and the intervillous spaces. The chorionic plate (great part of theplacenta on the
DISPLACEMENT OF THE OVARIES A web-based training in medical embryology. Through atrophy of the mesonephros the upper gubernaculum connects the ovary directly with the upper rear body wall and becomes designated as the suspensory ligament of ovary. The lower gubernaculum has its origin in the bottom side of the ovary and forms the ovarian ligament and, further down, the round ligament of uterus that reaches the genital PATHOLOGY OF THE URINARY SYSTEM A web-based training in medical embryology. Urachal fistula: In a urachal fistula a lumen remains over the whole length of the urachus because the atrophy of the allantois fails to take place. PANCREAS; DORSAL PANCREAS; VENTRAL PANCREAS The ventral pancreas anlage arises somewhat later (stage 13-14, ca. 32-33 days, 13) as a budding from the bile duct.Due to the 90 degree rotation of the stomach and the lengthening of the duodenal loop the bile duct with the gall bladder and the ventral pancreas are moved towards the rear, thus rotating around the duodenum and reaches then a position ventral to the dorsal pancreas.Introduction
Aide
Avertissements
Copyright
Crédits
Revue de presse
Français
Deutsch
English
EMBRYOLOGIE HUMAINE
EMBRYOGÉNÈSE
ORGANOGÉNÈSE
------------------------- Cours d'embryologie en ligne à l'usage des étudiants et étudiantesen médecine
Développé par les Universités de Fribourg, Lausanne et Berne(Suisse)
sous l'égide du Campus Virtuel Suisse Copyright protectedDetails
Copyright © 2024 ArchiveBay.com. All rights reserved. Terms of Use | Privacy Policy | DMCA | 2021 | Feedback | Advertising | RSS 2.0