SettingsEmbryology
3D ultrasound
3D ultrasound is a medical ultrasound technique, often used in obstetric ultrasonography, providing three dimensional images of the fetus.
3D ultrasound is a medical ultrasound technique, often used in obstetric ultrasonography, providing three dimensional images of the fetus.
Agenesis
In medicine, agenesis refers to the failure of an organ to develop during embryonic growth and development.
In medicine, agenesis refers to the failure of an organ to develop during embryonic growth and development.
Alar plate
The alar plate (or alar lamina) is a neural structure in the embryonic nervous system, part of the dorsal side of neural tube, that involves the communication of general somatic and genera...
The alar plate (or alar lamina) is a neural structure in the embryonic nervous system, part of the dorsal side of neural tube, that involves the communication of general somatic and genera...
Allantois
Allantois (plural allantoides or allantoises) is a part of a developing animal conceptus (which consists of all embryonic and extra-embryonic tissues).
Allantois (plural allantoides or allantoises) is a part of a developing animal conceptus (which consists of all embryonic and extra-embryonic tissues).
Amnion nodosum
Amnion nodosum are nodules on the fetal surface of the amnion, and is frequently present in oligohydramnios.
Amnion nodosum are nodules on the fetal surface of the amnion, and is frequently present in oligohydramnios.
Amniotic fluid
Amniotic fluid or liquor amnii is the nourishing and protecting liquid contained by the amniotic sac of a pregnant woman.
Amniotic fluid or liquor amnii is the nourishing and protecting liquid contained by the amniotic sac of a pregnant woman.
Angelo Ruffini
Angelo Ruffini (Pretare of Arquata del Tronto,1864 – 1929) was an Italian histologist and embryologist.
Angelo Ruffini (Pretare of Arquata del Tronto,1864 – 1929) was an Italian histologist and embryologist.
Angioblast
Here a new type of cell, the angioblast or vasoformative cell, is differentiated from the mesoderm.
Here a new type of cell, the angioblast or vasoformative cell, is differentiated from the mesoderm.
Anterior cardinal vein
The precardinal veins or anterior cardinal veins contribute to the formation of the internal jugular veins and together with the common cardinal vein form the superior vena cava.
The precardinal veins or anterior cardinal veins contribute to the formation of the internal jugular veins and together with the common cardinal vein form the superior vena cava.
Anterior neuropore
The anterior neuropore is a region corresponding to the opening of the embryonic neural tube in the anterior portion of the prosencephalon.
The anterior neuropore is a region corresponding to the opening of the embryonic neural tube in the anterior portion of the prosencephalon.
Aorta-gonad-mesonephros
The aorta-gonad-mesonephros is a region of embryonic mesoderm that develops during embryonic development from the para-aortic splanchnopleura in chick, mouse and human embryos.
The aorta-gonad-mesonephros is a region of embryonic mesoderm that develops during embryonic development from the para-aortic splanchnopleura in chick, mouse and human embryos.
Aortic arches
The aortic arches are a series of six paired embryological vascular structures which give rise to several major arteries.
The aortic arches are a series of six paired embryological vascular structures which give rise to several major arteries.
Apical ectodermal ridge
Apical Ectodermal Ridge (AER) The apical ectodermal ridge (AER) is a structure that forms from the ectodermal cells at the distal end of each limb bud and acts as a major signaling center ...
Apical Ectodermal Ridge (AER) The apical ectodermal ridge (AER) is a structure that forms from the ectodermal cells at the distal end of each limb bud and acts as a major signaling center ...
Aplasia
Aplasia is defined in general as "defective development or congenital absence of tissue" In the field of hematology, the term refers to "incomplete, retarded, or defective development, or cessat...
Aplasia is defined in general as "defective development or congenital absence of tissue" In the field of hematology, the term refers to "incomplete, retarded, or defective development, or cessat...
Aromatase deficiency
Aromatase deficiency is a condition resulting from insufficient production of the enzyme aromatase, which can lead to inappropriate virilization.
Aromatase deficiency is a condition resulting from insufficient production of the enzyme aromatase, which can lead to inappropriate virilization.
Atrial canal
In the developing heart, the constriction between the atrium and ventricle constitutes the atrial canal, and indicates the site of the future atrioventricular valves.
In the developing heart, the constriction between the atrium and ventricle constitutes the atrial canal, and indicates the site of the future atrioventricular valves.
Atrioventricular canal
In the developing heart, the constriction between the atrium and ventricle constitutes the atrial canal, and indicates the site of the future atrioventricular valves.
In the developing heart, the constriction between the atrium and ventricle constitutes the atrial canal, and indicates the site of the future atrioventricular valves.
Atrioventricular cushions
Atrioventricular cushions or endocardial cushions refers to a subset of cells in the primordial heart that play a vital role in proper heart septation.
Atrioventricular cushions or endocardial cushions refers to a subset of cells in the primordial heart that play a vital role in proper heart septation.
Auditory pit
The auditory pit, also known as the otic pit, is the first rudiment of the internal ear.
The auditory pit, also known as the otic pit, is the first rudiment of the internal ear.
Auditory vesicle
When the mouth of the auditory pit is closed, and thus a shut sac, the auditory vesicle (or otic vesicle), is formed; from it the epithelial lining of the membranous labyrinth is derived.
When the mouth of the auditory pit is closed, and thus a shut sac, the auditory vesicle (or otic vesicle), is formed; from it the epithelial lining of the membranous labyrinth is derived.
Azygos lobe
In human anatomy, an azygos lobe is a rare congenital variation of the upper lobe of the right lung.
In human anatomy, an azygos lobe is a rare congenital variation of the upper lobe of the right lung.
Basal plate (neural tube)
In the developing nervous system, the basal plate is the region of the neural tube ventral to the sulcus limitans.
In the developing nervous system, the basal plate is the region of the neural tube ventral to the sulcus limitans.
Basal plate (placenta)
Changes in the placenta involve the disappearance of the greater portion of the stratum compactum, but the deeper part of this layer persists and is condensed to form what is known as the basal pla...
Changes in the placenta involve the disappearance of the greater portion of the stratum compactum, but the deeper part of this layer persists and is condensed to form what is known as the basal pla...
Bedford Stem Cell Research Foundation
Bedford Stem Cell Research Foundation is a non-profit Institute that conducts stem cell research for diseases and conditions that currently have no known cure.
Bedford Stem Cell Research Foundation is a non-profit Institute that conducts stem cell research for diseases and conditions that currently have no known cure.
Bilaminar blastocyst
Bilaminar blastocyst or Bilaminar disc refers to the epiblast and the hypoblast, evolved from the embryoblast.
Bilaminar blastocyst or Bilaminar disc refers to the epiblast and the hypoblast, evolved from the embryoblast.
Bilaminar disc
Bilaminar disc refers to the epiblast and the hypoblast, evolved from the embryoblast.
Bilaminar disc refers to the epiblast and the hypoblast, evolved from the embryoblast.
Blastocyst
The blastocyst is a structure formed in the early embryogenesis of mammals, after the formation of the morula.
The blastocyst is a structure formed in the early embryogenesis of mammals, after the formation of the morula.
Blastoderm
A blastoderm is the layer of cells formed at one pole of macrolecithal eggs such as the yolky egg of birds.
A blastoderm is the layer of cells formed at one pole of macrolecithal eggs such as the yolky egg of birds.
Blastomere
A blastomere is a type of cell produced by division of the egg after fertilization.
A blastomere is a type of cell produced by division of the egg after fertilization.
Blood island
Blood islands are structures in the developing embryo which lead to many different parts of the circulatory system.
Blood islands are structures in the developing embryo which lead to many different parts of the circulatory system.
Blood island of umbilical vesicle
Blood islands are structures in the developing embryo which lead to many different parts of the circulatory system.
Blood islands are structures in the developing embryo which lead to many different parts of the circulatory system.
Body-stalk
The caudal end of the embryo is at first connected to the chorion by a band of mesoderm called the body-stalk, but with the formation of the caudal fold the body-stalk assumes a ventral position...
The caudal end of the embryo is at first connected to the chorion by a band of mesoderm called the body-stalk, but with the formation of the caudal fold the body-stalk assumes a ventral position...
Bootstrapping (biology)
The idea of bootstrapping is significant in a number of fields in the biological sciences.
The idea of bootstrapping is significant in a number of fields in the biological sciences.
Branchiomeric musculature
Branchiomeric muscles are striated muscles of the head and neck.
Branchiomeric muscles are striated muscles of the head and neck.
Buccopharyngeal membrane
The region where the crescentic masses of the ectoderm and endoderm come into direct contact with each other constitutes a thin membrane, the buccopharyngeal membrane (or oropharyngeal membra...
The region where the crescentic masses of the ectoderm and endoderm come into direct contact with each other constitutes a thin membrane, the buccopharyngeal membrane (or oropharyngeal membra...
Bulbus cordis
The bulbus cordis (also known as the conotruncus) lies ventral to the primitive ventricle after the developing heart assumes its S-shaped form.
The bulbus cordis (also known as the conotruncus) lies ventral to the primitive ventricle after the developing heart assumes its S-shaped form.
Cardiac neural crest
The cardiac neural crest is a form of neural crest.
The cardiac neural crest is a form of neural crest.
Cardiac neural crest complex
The cardiac neural crest complex is a form of neural crest.
The cardiac neural crest complex is a form of neural crest.
Cardinal veins
The ascending veins return the blood from the parietes of the trunk and from the Wolffian bodies, and are called cardinal veins.
The ascending veins return the blood from the parietes of the trunk and from the Wolffian bodies, and are called cardinal veins.
Carnegie stages
In embryology, Carnegie stages are a standardized system of 23 stages used to provide a unified developmental chronology of the vertebrate embryo.
In embryology, Carnegie stages are a standardized system of 23 stages used to provide a unified developmental chronology of the vertebrate embryo.
Caudal cell mass
In humans and other mammals, the caudal cell mass is the aggregate of undifferentiated cells at the caudal end on the spine, sometimes called the tail bud in humans.
In humans and other mammals, the caudal cell mass is the aggregate of undifferentiated cells at the caudal end on the spine, sometimes called the tail bud in humans.
Cephalic flexure
The cephalic flexure is the first flexure, or bend, of the embryonic brain; it appears in the region of the mid-brain.
The cephalic flexure is the first flexure, or bend, of the embryonic brain; it appears in the region of the mid-brain.
Cerebro-corporal coefficient
The cerebro-corporal coefficient (CCC) is an ultrasound measurement defined as the relation of the length of the head part to the body part of the embryo between the 10th and 14th weeks of pregnancy.
The cerebro-corporal coefficient (CCC) is an ultrasound measurement defined as the relation of the length of the head part to the body part of the embryo between the 10th and 14th weeks of pregnancy.
Cervical sinus
The mandibular and hyoid arches grow more rapidly than those behind them, with the result that the latter become, to a certain extent, telescoped within the former, and a deep depression, the cervi...
The mandibular and hyoid arches grow more rapidly than those behind them, with the result that the latter become, to a certain extent, telescoped within the former, and a deep depression, the cervi...
Chondrogenesis
Chondrogenesis is the process by which cartilage is developed.
Chondrogenesis is the process by which cartilage is developed.
Chordamesoderm
Chordamesoderm, also known as axial mesoderm, is a type of mesoderm that lies along the central axis, under the neural tube.
Chordamesoderm, also known as axial mesoderm, is a type of mesoderm that lies along the central axis, under the neural tube.
Choriogenesis
In developmental biology, choriogenesis is the formation of the chorion, an outer membrane of the placenta that eventually forms chorionic villi that allow the transfer of blood and nutrients fr...
In developmental biology, choriogenesis is the formation of the chorion, an outer membrane of the placenta that eventually forms chorionic villi that allow the transfer of blood and nutrients fr...
Chorion
The chorion is one of the membranes that exist during pregnancy between the developing fetus and mother.
The chorion is one of the membranes that exist during pregnancy between the developing fetus and mother.
Chorionic vessels
Chorionic (plate) vessels are blood vessels, including both arteries and veins, that carry blood through the chorion in the feto-placental circulation.
Chorionic (plate) vessels are blood vessels, including both arteries and veins, that carry blood through the chorion in the feto-placental circulation.
Chorionic villi
Chorionic villi are villi that sprout from the chorion in order to give a maximum area of contact with the maternal blood.
Chorionic villi are villi that sprout from the chorion in order to give a maximum area of contact with the maternal blood.
Cloaca (embryology)
The cloaca is a structure in the development of the urinary and reproductive organs.
The cloaca is a structure in the development of the urinary and reproductive organs.
Cloacal membrane
The cloacal membrane is the membrane that covers the embryonic cloaca when still in the development of the urinary and reproductive organs.
The cloacal membrane is the membrane that covers the embryonic cloaca when still in the development of the urinary and reproductive organs.
Comparative embryology
Comparative Embryology is the branch of embryology that compares and contrasts embryos of different species.
Comparative Embryology is the branch of embryology that compares and contrasts embryos of different species.
Conceptus
Conceptus (latin is conceptio, derivatives of zygote) denotes the embryo and its adnexa (appendages or adjunct parts) or associated membranes (i.e.
Conceptus (latin is conceptio, derivatives of zygote) denotes the embryo and its adnexa (appendages or adjunct parts) or associated membranes (i.e.
Connecting stalk
The connecting stalk is a yolk sac diverticulum.
The connecting stalk is a yolk sac diverticulum.
Cranial neural crest
The cranial neural crest is a form of neural crest.
The cranial neural crest is a form of neural crest.
Crista dividends
Crista dividens is a structure in the developing heart of the human embryo that divides the right ventricle in a way such that it creates a pan systolic murmur in the same way as the foramen ovale.
Crista dividens is a structure in the developing heart of the human embryo that divides the right ventricle in a way such that it creates a pan systolic murmur in the same way as the foramen ovale.
Cutis plate
The cutis plate is the dorsal portion of the paraxial mesoderm somite which gives rise to dermis.
The cutis plate is the dorsal portion of the paraxial mesoderm somite which gives rise to dermis.
Cytotrophoblast
The cytotrophoblast (or layer of Langhans) is the inner layer of the trophoblast, interior to the syncytiotrophoblast in an embryo.
The cytotrophoblast (or layer of Langhans) is the inner layer of the trophoblast, interior to the syncytiotrophoblast in an embryo.
Dacryocystocele
A dacryocystocele (also known as a timo cyst) is a benign, bluish-gray mass in the inferomedial canthus that forms as a result of a narrowing or obstruction of the nasolacrimal duct, usually dur...
A dacryocystocele (also known as a timo cyst) is a benign, bluish-gray mass in the inferomedial canthus that forms as a result of a narrowing or obstruction of the nasolacrimal duct, usually dur...
Definitive urogenital sinus
The definitive urogenital sinus is a part of the human body only present in the development of the urinary and reproductive organs.
The definitive urogenital sinus is a part of the human body only present in the development of the urinary and reproductive organs.
Dermatomal mesenchyme
The dermatomal mesenchyme or cutis plate is the dorsal portion of the paraxial mesoderm somite which gives rise to dermis.
The dermatomal mesenchyme or cutis plate is the dorsal portion of the paraxial mesoderm somite which gives rise to dermis.
Dorsal aorta
Each primitive aorta receives anteriorly a vein—the vitelline vein—from the yolk-sac, and is prolonged backward on the lateral aspect of the notochord under the name of the dorsal aorta.
Each primitive aorta receives anteriorly a vein—the vitelline vein—from the yolk-sac, and is prolonged backward on the lateral aspect of the notochord under the name of the dorsal aorta.
Ducts of Cuvier
During development of the veins, the first indication of a parietal system consists in the appearance of two short transverse veins, the ducts of Cuvier (or common cardinal veins), which o...
During development of the veins, the first indication of a parietal system consists in the appearance of two short transverse veins, the ducts of Cuvier (or common cardinal veins), which o...
Ductus arteriosus
In the developing fetus, the ductus arteriosus (DA), also called the ductus Botalli, is a shunt connecting the pulmonary artery to the aortic arch.
In the developing fetus, the ductus arteriosus (DA), also called the ductus Botalli, is a shunt connecting the pulmonary artery to the aortic arch.
Ductus venosus
In the fetus, the ductus venosus shunts approximately half of the blood flow of the umbilical vein directly to the inferior vena cava.
In the fetus, the ductus venosus shunts approximately half of the blood flow of the umbilical vein directly to the inferior vena cava.
Dysgenesis (embryology)
Dysgenesis The term dysgenesis is used to describe abnormal organ development during embryonic growth and development.
Dysgenesis The term dysgenesis is used to describe abnormal organ development during embryonic growth and development.
Embryo
An embryo is a multicellular diploid eukaryote in its earliest stage of development, from the time of first cell division until birth, hatching, or germination.
An embryo is a multicellular diploid eukaryote in its earliest stage of development, from the time of first cell division until birth, hatching, or germination.
Embryogenesis
Embryogenesis is the process by which the embryo is formed and develops, until it develops into a fetus.
Embryogenesis is the process by which the embryo is formed and develops, until it develops into a fetus.
Embryoid body
Embryoid bodies are aggregates of cells derived from embryonic stem cells, and have been studied for years with mouse embryonic stem cells.
Embryoid bodies are aggregates of cells derived from embryonic stem cells, and have been studied for years with mouse embryonic stem cells.
Embryomics
Embryomics is the identification, characterization and study of the diverse cell types which arise during embryogenesis, especially as this relates to the location and developmental history of c...
Embryomics is the identification, characterization and study of the diverse cell types which arise during embryogenesis, especially as this relates to the location and developmental history of c...
Embryonated
Embryonated and Unembryonated are terms generally used in referring to eggs or, in botany, to seeds.
Embryonated and Unembryonated are terms generally used in referring to eggs or, in botany, to seeds.
Embryonic disc
The floor of the amniotic cavity is formed by the embryonic disk composed of a layer of prismatic cells, the embryonic ectoderm, derived from the inner cell-mass and lying in apposition with the...
The floor of the amniotic cavity is formed by the embryonic disk composed of a layer of prismatic cells, the embryonic ectoderm, derived from the inner cell-mass and lying in apposition with the...
Embryonic disk
The floor of the amniotic cavity is formed by the embryonic disk (or embryonic disc) composed of a layer of prismatic cells, the embryonic ectoderm, derived from the inner cell-mass and ly...
The floor of the amniotic cavity is formed by the embryonic disk (or embryonic disc) composed of a layer of prismatic cells, the embryonic ectoderm, derived from the inner cell-mass and ly...
Embryonic heart
The embryonic heart starts developing from two distinct vascular tubes of the embryo around day 19 of the embryo's existence, under the signals of genetic expression arrived from the surrounding...
The embryonic heart starts developing from two distinct vascular tubes of the embryo around day 19 of the embryo's existence, under the signals of genetic expression arrived from the surrounding...
Embryonic ventricle
The embryonic ventricle or primitive ventricle of the developing heart gives rise to the trabeculated parts of the left and right ventricles.
The embryonic ventricle or primitive ventricle of the developing heart gives rise to the trabeculated parts of the left and right ventricles.
Endocardial cushions
Endocardial cushions refers to a subset of cells in the primordial heart that play a vital role in proper heart septation.
Endocardial cushions refers to a subset of cells in the primordial heart that play a vital role in proper heart septation.
Endoderm
Endoderm, (sometimes called Entoderm) is one of the germ layers formed during animal embryogenesis.
Endoderm, (sometimes called Entoderm) is one of the germ layers formed during animal embryogenesis.
Enterocoely
Enterocoely (adjective forms: enterocoelic or enterocoelous) is a process by which embryos develop.
Enterocoely (adjective forms: enterocoelic or enterocoelous) is a process by which embryos develop.
Epiblast
In amniote animal embryology, the epiblast is a tissue type derived either from the inner cell mass in mammals or the blastodisc in birds and reptiles.
In amniote animal embryology, the epiblast is a tissue type derived either from the inner cell mass in mammals or the blastodisc in birds and reptiles.
European Assisted Conception Consortium
The European Assisted Conception Consortium or EACC wants to bring together national ART regulators and practitioners within the European Union for professional cooperation and joint action.
The European Assisted Conception Consortium or EACC wants to bring together national ART regulators and practitioners within the European Union for professional cooperation and joint action.
European Society of Human Reproduction and Embryology
The European Society of Human Reproduction and Embryology was founded in 1985 by Robert Edwards (University of Cambridge) and J. Cohen (Paris), who felt that the study and research in the field...
The European Society of Human Reproduction and Embryology was founded in 1985 by Robert Edwards (University of Cambridge) and J. Cohen (Paris), who felt that the study and research in the field...
Extra-embryonic coelom
The extraembryonic coelom (or Chorionic cavity) is a portion of the conceptus consisting of a cavity between Heuser's membrane and the Trophoblast.
The extraembryonic coelom (or Chorionic cavity) is a portion of the conceptus consisting of a cavity between Heuser's membrane and the Trophoblast.
Extraembryonic coelom
The extraembryonic coelom (or Chorionic cavity) is a portion of the conceptus consisting of a cavity between Heuser's membrane and the Trophoblast.
The extraembryonic coelom (or Chorionic cavity) is a portion of the conceptus consisting of a cavity between Heuser's membrane and the Trophoblast.
Fetal circulation
The fetal circulation is the circulatory system of a human fetus, often encompassing the entire fetoplacental circulation that also includes the umbilical cord and the blood vessels within...
The fetal circulation is the circulatory system of a human fetus, often encompassing the entire fetoplacental circulation that also includes the umbilical cord and the blood vessels within...
Fetal echocardiography
Fetal echocardiography provides a valuable means to better understand intrauterine growth and development of the heart and great vessels.
Fetal echocardiography provides a valuable means to better understand intrauterine growth and development of the heart and great vessels.
Fetal fibronectin
Fetal fibronectin (fFN) is a protein produced by fetal cells and a type of fibronectin.
Fetal fibronectin (fFN) is a protein produced by fetal cells and a type of fibronectin.
Fetal membranes
The fetal membranes, or chorioamniotic membranes, are the amnion and chorion which surround and protect a developing fetus.
The fetal membranes, or chorioamniotic membranes, are the amnion and chorion which surround and protect a developing fetus.
Fetal pole
The fetal pole is a thickening on the margin of the yolk sac of a fetus during pregnancy.
The fetal pole is a thickening on the margin of the yolk sac of a fetus during pregnancy.
Fetus
A fetus (; also spelled foetus, fœtus, faetus, or fætus, see below) is a developing mammal or other viviparous vertebrate after the embryonic stage and be...
A fetus (; also spelled foetus, fœtus, faetus, or fætus, see below) is a developing mammal or other viviparous vertebrate after the embryonic stage and be...
Fetus (biology)
A fetus (sometimes spelled foetus or fœtus) is a stage in the development of viviparous organisms.
A fetus (sometimes spelled foetus or fœtus) is a stage in the development of viviparous organisms.
First pharyngeal arch
The first branchial arch, also called the first pharyngeal arch and mandibular arch, is the first of six branchial arches that develops in fetal life during the fourth week of develo...
The first branchial arch, also called the first pharyngeal arch and mandibular arch, is the first of six branchial arches that develops in fetal life during the fourth week of develo...
Floor plate
The floor plate is a structure integral to the developing nervous system of vertebrate organisms.
The floor plate is a structure integral to the developing nervous system of vertebrate organisms.
Foramen cecum (tongue)
The dorsum of the tongue is convex and marked by a median sulcus, which divides it into symmetrical halves; this sulcus ends behind, about 2.5 cm from the root of the organ, in a depression, the fo...
The dorsum of the tongue is convex and marked by a median sulcus, which divides it into symmetrical halves; this sulcus ends behind, about 2.5 cm from the root of the organ, in a depression, the fo...
Foramen ovale (heart)
In the fetal heart, the foramen ovale (also ostium secundum of Born or falx septi) allows blood to enter the left atrium from the right atrium.
In the fetal heart, the foramen ovale (also ostium secundum of Born or falx septi) allows blood to enter the left atrium from the right atrium.
Foramen secundum
The ostium secundum is a foramen in the septum primum.
The ostium secundum is a foramen in the septum primum.
Foregut
The foregut is the anterior part of the alimentary canal, from the mouth to the duodenum at the entrance of the bile duct.
The foregut is the anterior part of the alimentary canal, from the mouth to the duodenum at the entrance of the bile duct.
Frontonasal prominence
During the third week of embryonic development, two areas of thickened ectoderm, the olfactory areas, appear immediately under the fore-brain in the anterior wall of the stomodeum, one on either side ...
During the third week of embryonic development, two areas of thickened ectoderm, the olfactory areas, appear immediately under the fore-brain in the anterior wall of the stomodeum, one on either side ...
Ganglionic eminence
In neuroanatomy and neuroembryology, a ganglionic eminence (GE) is a transitory brain structure present in the embryonic and fetal stages of brain development.
In neuroanatomy and neuroembryology, a ganglionic eminence (GE) is a transitory brain structure present in the embryonic and fetal stages of brain development.
Gastrulation
Gastrulation is a phase early in the embryonic development of most animals, during which the single-layered blastula is reorganized into a trilaminar ("three-layered") structure known as the ...
Gastrulation is a phase early in the embryonic development of most animals, during which the single-layered blastula is reorganized into a trilaminar ("three-layered") structure known as the ...
Germ layer
A germ layer, occasionally referred to as a germinal epithelium, is a group of cells, formed during animal embryogenesis.
A germ layer, occasionally referred to as a germinal epithelium, is a group of cells, formed during animal embryogenesis.
Gestational sac
The gestational sac is the only available intrauterine structure that can be used to determine if an intrauterine pregnancy exists, until the embryo is identified.
The gestational sac is the only available intrauterine structure that can be used to determine if an intrauterine pregnancy exists, until the embryo is identified.
Gonadogenesis
Gonadogenesis is one of the many particular stages organogenesis.
Gonadogenesis is one of the many particular stages organogenesis.
Gubernaculum testis
The paired Gubernacula are embryonic structures which begin as undifferentiated mesenchyme attaching to the caudal end of the gonads (testes in males and ovaries in females).
The paired Gubernacula are embryonic structures which begin as undifferentiated mesenchyme attaching to the caudal end of the gonads (testes in males and ovaries in females).
Hamburger-Hamilton stages
In developmental biology, the Hamburger-Hamilton stages (HH) are a series of 46 chronological stages in chick development, starting from laying of the egg and ending with a newly hatched chick.
In developmental biology, the Hamburger-Hamilton stages (HH) are a series of 46 chronological stages in chick development, starting from laying of the egg and ending with a newly hatched chick.
Heuser's membrane
Heuser's membrane (or the exocoelomic membrane) is a short lived combination of hypoblast cells and extracellular matrix.
Heuser's membrane (or the exocoelomic membrane) is a short lived combination of hypoblast cells and extracellular matrix.
Histogenesis
Histogenesis is the formation of different tissues from undifferentiated cells.
Histogenesis is the formation of different tissues from undifferentiated cells.
Hyoid arch
The hyoid arch (or second branchial arch) assists in forming the side and front of the neck.
The hyoid arch (or second branchial arch) assists in forming the side and front of the neck.
Hypoblast
The hypoblast is a tissue type that forms from the inner cell mass.
The hypoblast is a tissue type that forms from the inner cell mass.
Hypobranchial eminence
The hypobranchial eminence is an embryogenic structure which forms the 1/3 posterior part (copula) of adult tongue during fetal development.
The hypobranchial eminence is an embryogenic structure which forms the 1/3 posterior part (copula) of adult tongue during fetal development.
Hypopharyngeal eminence
The hypopharyngeal eminence or hypobranchial eminence is an embryogenic structure which forms the 1/3 posterior part of adult tongue during fetal development.
The hypopharyngeal eminence or hypobranchial eminence is an embryogenic structure which forms the 1/3 posterior part of adult tongue during fetal development.
Iberian Latin American Symposium Terminology
At the Iberian Latin American Symposia Terminology (SILAT) of anatomy, histology and embryology is studied, analyzes, translates and disseminates international morphological terminology, f...
At the Iberian Latin American Symposia Terminology (SILAT) of anatomy, histology and embryology is studied, analyzes, translates and disseminates international morphological terminology, f...
Implantation (human embryo)
In humans, implantation is the beginning of pregnancy, in which the embryo Adheres to the wall of the uterus.
In humans, implantation is the beginning of pregnancy, in which the embryo Adheres to the wall of the uterus.
Interatrial septum
The interatrial septum is the wall of tissue that separates the right and left atria of the heart.
The interatrial septum is the wall of tissue that separates the right and left atria of the heart.
Interferon tau
Found in cows and sheep, Interferon tau is the signal from the developing embryo to the mother that she is pregnant.
Found in cows and sheep, Interferon tau is the signal from the developing embryo to the mother that she is pregnant.
Intermaxillary segment
More precisely, the rounded lateral angles of the medial process constitute the globular processes.
More precisely, the rounded lateral angles of the medial process constitute the globular processes.
Intermediate mesoderm
Intermediate mesoderm is a type of mesoderm that is located between the paraxial mesoderm and the lateral plate.
Intermediate mesoderm is a type of mesoderm that is located between the paraxial mesoderm and the lateral plate.
Intermediate trophoblast
Intermediate trophoblast is a distinct subtype of trophoblastic tissue that arises from the cytotrophoblast.
Intermediate trophoblast is a distinct subtype of trophoblastic tissue that arises from the cytotrophoblast.
Intermediate zone of cortex
In human embryology, the intermediate zone of the cortex is a layer in the neural tube between the marginal zone and the pia mater.
In human embryology, the intermediate zone of the cortex is a layer in the neural tube between the marginal zone and the pia mater.
Intervillous space
With this physiologic destructive process, the maternal blood vessels of the endometrium are opened, with the result that the spaces in the trophoblastic network are filled with maternal blood; thes...
With this physiologic destructive process, the maternal blood vessels of the endometrium are opened, with the result that the spaces in the trophoblastic network are filled with maternal blood; thes...
Intra-embryonic coelom
In the development of the human embryo the intraembryonic coelom is a portion of the conceptus forming in the mesoderm.
In the development of the human embryo the intraembryonic coelom is a portion of the conceptus forming in the mesoderm.
Intraembryonic coelom
In the development of the human embryo the intraembryonic coelom (or somatic coelom) is a portion of the conceptus forming in the mesoderm.
In the development of the human embryo the intraembryonic coelom (or somatic coelom) is a portion of the conceptus forming in the mesoderm.
J. W. Jenkinson Memorial Lectureship
John Wilfred Jenkinson was a pioneer in the field of comparative developmental biology and one of the first to introduce experimental embryology to the UK at the start of the twentieth century.
John Wilfred Jenkinson was a pioneer in the field of comparative developmental biology and one of the first to introduce experimental embryology to the UK at the start of the twentieth century.
Kidney development
Kidney development, or nephrogenesis, describes the embryologic origins of the kidney, a major organ in the urinary system.
Kidney development, or nephrogenesis, describes the embryologic origins of the kidney, a major organ in the urinary system.
Labioscrotal swelling
The labioscrotal folds are paired structures in the human embryo that represent the final stage of development of the caudal end of the external genitals before sexual differentiation.
The labioscrotal folds are paired structures in the human embryo that represent the final stage of development of the caudal end of the external genitals before sexual differentiation.
Lamellar body count
The lamellar body count is a test for assessing fetal lung maturity.
The lamellar body count is a test for assessing fetal lung maturity.
Lateral lingual swelling
More recent researches, however, show that this part of the tongue is mainly, if not entirely, developed from a pair of lateral swellings (or distal tongue bud) which rise from the inner ...
More recent researches, however, show that this part of the tongue is mainly, if not entirely, developed from a pair of lateral swellings (or distal tongue bud) which rise from the inner ...
Lateral nasal prominence
By the upgrowth of the surrounding parts the olfactory areas are converted into pits, the olfactory pits, which indent the fronto-nasal process and divide it into a medial and two lateral nasal pro...
By the upgrowth of the surrounding parts the olfactory areas are converted into pits, the olfactory pits, which indent the fronto-nasal process and divide it into a medial and two lateral nasal pro...
Lateral plate mesoderm
Lateral plate mesoderm is a type of mesoderm that is found at the periphery of the embryo.
Lateral plate mesoderm is a type of mesoderm that is found at the periphery of the embryo.
Lens placode
The Lens placode is a thickened portion of ectoderm which serves as the precursor to the lens.
The Lens placode is a thickened portion of ectoderm which serves as the precursor to the lens.
Limb bud
In embryology, the limb bud is a structure formed by the developing limb, derived from lateral plate mesoderm.
In embryology, the limb bud is a structure formed by the developing limb, derived from lateral plate mesoderm.
Lung buds
The cephalic part of the laryngo-tracheal tube becomes the larynx, and its next succeeding part the trachea, while from its caudal end two lateral outgrowths, the right and left lung buds, arise...
The cephalic part of the laryngo-tracheal tube becomes the larynx, and its next succeeding part the trachea, while from its caudal end two lateral outgrowths, the right and left lung buds, arise...
Mandibular prominence
The mandibular prominence is an embryological structure which gives rise to the lower portion of the face.
The mandibular prominence is an embryological structure which gives rise to the lower portion of the face.
Matrotrophy
In plant sciences, matrotrophy (maternal care) is considered a critical innovation preceding the origin of embryophytes and thus essential to the evolution of land plants.
In plant sciences, matrotrophy (maternal care) is considered a critical innovation preceding the origin of embryophytes and thus essential to the evolution of land plants.
Maxillary prominence
Continuous with the dorsal end of the mandibular arch, and growing forward from its cephalic border, is a triangular process, the maxillary process (or maxillary prominence), the ventral e...
Continuous with the dorsal end of the mandibular arch, and growing forward from its cephalic border, is a triangular process, the maxillary process (or maxillary prominence), the ventral e...
Meckel's cartilage
The cartilaginous bar of the mandibular arch is formed by what are known as Meckel’s cartilages (right and left) also known as Meckelian cartilages; above this the incus and malleus are de...
The cartilaginous bar of the mandibular arch is formed by what are known as Meckel’s cartilages (right and left) also known as Meckelian cartilages; above this the incus and malleus are de...
Medial nasal prominence
The medial nasal prominence (nasomedial) is an embryological structure that forms the upper lip and nose.
The medial nasal prominence (nasomedial) is an embryological structure that forms the upper lip and nose.
Mesoderm
In all bilaterian animals, the mesoderm is one of the three primary germ cell layers in the very early embryo.
In all bilaterian animals, the mesoderm is one of the three primary germ cell layers in the very early embryo.
Mesonephros
The mesonephros (Greek for "middle kidney") is one of three excretory organs that develop in vertebrates.
The mesonephros (Greek for "middle kidney") is one of three excretory organs that develop in vertebrates.
Metanephric blastema
The metanephric blastema (or metanephric mesenchyme, or metanephric mesoderm) is one of the two embryological structures that give rise to the kidney (the other is the ureteric bud.)...
The metanephric blastema (or metanephric mesenchyme, or metanephric mesoderm) is one of the two embryological structures that give rise to the kidney (the other is the ureteric bud.)...
Metanephrogenic blastema
The metanephrogenic blastema or metanephric blastema is one of the two embryological structures that give rise to the kidney The metanephric blastema mostly develops into nephrons, but ca...
The metanephrogenic blastema or metanephric blastema is one of the two embryological structures that give rise to the kidney The metanephric blastema mostly develops into nephrons, but ca...
Monoembryony
Monoembryony is when one only one seedling emerges from a seed.
Monoembryony is when one only one seedling emerges from a seed.
Morula
A morula is an embryo at an early stage of embryonic development, consisting of cells in a solid ball contained within the zona pellucida.
A morula is an embryo at an early stage of embryonic development, consisting of cells in a solid ball contained within the zona pellucida.
Myotome
In vertebrate embryonic development, a myotome is a group of tissues formed from somites that develop into the body wall muscle.
In vertebrate embryonic development, a myotome is a group of tissues formed from somites that develop into the body wall muscle.
Müllerian duct
Müllerian ducts (or paramesonephric ducts) are paired ducts of the embryo that run down the lateral sides of the urogenital ridge and terminate at the Müllerian eminence in the primitive u...
Müllerian ducts (or paramesonephric ducts) are paired ducts of the embryo that run down the lateral sides of the urogenital ridge and terminate at the Müllerian eminence in the primitive u...
Nasal pit
By the upgrowth of the surrounding parts the olfactory areas are converted into pits, the nasal pits or olfactory pits, which indent the fronto-nasal process and divide it into a medial an...
By the upgrowth of the surrounding parts the olfactory areas are converted into pits, the nasal pits or olfactory pits, which indent the fronto-nasal process and divide it into a medial an...
Nasal placode
The nasal placode (or olfactory placode) gives rise to the olfactory epithelium of the nose.
The nasal placode (or olfactory placode) gives rise to the olfactory epithelium of the nose.
Nephrotome
The nephrotome is a section of the mesoderm.
The nephrotome is a section of the mesoderm.
Neural development
Neural development comprises the processes that generate, shape, and reshape the nervous system, from the earliest stages of embryogenesis to the final years of life.
Neural development comprises the processes that generate, shape, and reshape the nervous system, from the earliest stages of embryogenesis to the final years of life.
Neural development in humans
The study of neural development draws on both neuroscience and developmental biology to describe the cellular and molecular mechanisms by which complex nervous systems emerge during embryonic de...
The study of neural development draws on both neuroscience and developmental biology to describe the cellular and molecular mechanisms by which complex nervous systems emerge during embryonic de...
Neural folds
These are named the neural folds; they commence some little distance behind the anterior end of the embryonic disk, where they are continuous with each other, and from there gradually extend ba...
These are named the neural folds; they commence some little distance behind the anterior end of the embryonic disk, where they are continuous with each other, and from there gradually extend ba...
Neural tube
In the developing vertebrate, the neural tube is the embryo's precursor to the central nervous system, which comprises the brain and spinal cord.
In the developing vertebrate, the neural tube is the embryo's precursor to the central nervous system, which comprises the brain and spinal cord.
Neurogenic placodes
A neurogenic placode is an area of thickening in the embryonic epithelial layer where some organ or structure later develops.
A neurogenic placode is an area of thickening in the embryonic epithelial layer where some organ or structure later develops.
Neuromere
Neuromeres are morphologically or molecularly defined transient segments of the early developing brain.
Neuromeres are morphologically or molecularly defined transient segments of the early developing brain.
Neurula
A Neurula is an embryo at the early stage of development in which neurulation occurs.
A Neurula is an embryo at the early stage of development in which neurulation occurs.
Nodal signaling
Nodal signaling is a signal transduction pathway that is important in pattern formation and differentiation during embryo development.
Nodal signaling is a signal transduction pathway that is important in pattern formation and differentiation during embryo development.
Notochord
The notochord is a flexible, rod-shaped body found in embryos of all chordates.
The notochord is a flexible, rod-shaped body found in embryos of all chordates.
Olfactory pit
By the upgrowth of the surrounding parts the olfactory areas are converted into pits, the olfactory pits, which indent the fronto-nasal process and divide it into a medial and two lateral nasal ...
By the upgrowth of the surrounding parts the olfactory areas are converted into pits, the olfactory pits, which indent the fronto-nasal process and divide it into a medial and two lateral nasal ...
Oocyte activation
Oocyte (or ovum/egg) activation is a series of processes that occur in the oocyte after fertilisation.
Oocyte (or ovum/egg) activation is a series of processes that occur in the oocyte after fertilisation.
Optic cup (embryology)
During embryonic development of the eye, the outer wall of the bulb of the optic vesicles becomes thickened and invaginated, and the bulb is thus converted into a cup, the optic cup (or ophth...
During embryonic development of the eye, the outer wall of the bulb of the optic vesicles becomes thickened and invaginated, and the bulb is thus converted into a cup, the optic cup (or ophth...
Optic stalk
The optic vesicles project toward the sides of the head, and the peripheral part of each expands to form a hollow bulb, while the proximal part remains narrow and constitutes the optic stalk.
The optic vesicles project toward the sides of the head, and the peripheral part of each expands to form a hollow bulb, while the proximal part remains narrow and constitutes the optic stalk.
Optic vesicles
These diverticula make their appearance before the closure of the anterior end of the neural tube; after the closure of the tube they are known as the optic vesicles.
These diverticula make their appearance before the closure of the anterior end of the neural tube; after the closure of the tube they are known as the optic vesicles.
Organogenesis
In animal development, organogenesis (organo-genesis, compound of the Greek words όργανον "that with which one works", and γένεσις "origin, creation, generation") is the process by which...
In animal development, organogenesis (organo-genesis, compound of the Greek words όργανον "that with which one works", and γένεσις "origin, creation, generation") is the process by which...
Ostium primum
In the developing heart, the atria initially communicate with each other by an opening between the free edge of the septum primum and the AV cushions, known as the ostium primum (interatrial ...
In the developing heart, the atria initially communicate with each other by an opening between the free edge of the septum primum and the AV cushions, known as the ostium primum (interatrial ...
Ostium secundum
The ostium secundum (or foramen secundum) is a foramen in the septum primum.
The ostium secundum (or foramen secundum) is a foramen in the septum primum.
Otic placode
In embryology, the otic placode is a thickening of the ectoderm on the outer surface of a developing embryo from which the ear develops.
In embryology, the otic placode is a thickening of the ectoderm on the outer surface of a developing embryo from which the ear develops.
Otic vesicle
When the mouth of the auditory pit is closed, and thus a shut sac, the auditory vesicle (or otic vesicle), is formed; from it the epithelial lining of the membranous labyrinth is derived.
When the mouth of the auditory pit is closed, and thus a shut sac, the auditory vesicle (or otic vesicle), is formed; from it the epithelial lining of the membranous labyrinth is derived.
Pancreatic bud
The ventral and dorsal pancreatic buds (or pancreatic diverticula) are outgrowths of the duodenum during human embryogenesis.
The ventral and dorsal pancreatic buds (or pancreatic diverticula) are outgrowths of the duodenum during human embryogenesis.
Paramesonephric duct
Müllerian ducts (or paramesonephric ducts) are paired ducts of the embryo that run down the lateral sides of the urogenital ridge and terminate at the Müllerian eminence in the primitive u...
Müllerian ducts (or paramesonephric ducts) are paired ducts of the embryo that run down the lateral sides of the urogenital ridge and terminate at the Müllerian eminence in the primitive u...
Paraxial mesoderm
Paraxial mesoderm is the area of mesoderm that forms just lateral to the neural tube on both sides.
Paraxial mesoderm is the area of mesoderm that forms just lateral to the neural tube on both sides.
Persistent thyroglossal duct
A persistent thyroglossal duct is a usually benign medical condition in which the thyroglossal duct, a structure usually only found during embryonic development, fails to atrophy.
A persistent thyroglossal duct is a usually benign medical condition in which the thyroglossal duct, a structure usually only found during embryonic development, fails to atrophy.
Pharyngeal arch
In the development of vertebrate animals, the pharyngeal arches are anlage for a multitude of structures.
In the development of vertebrate animals, the pharyngeal arches are anlage for a multitude of structures.
Pharyngeal groove
A pharyngeal groove is the counterpart of the branchial pouch on the ectodermal side.
A pharyngeal groove is the counterpart of the branchial pouch on the ectodermal side.
Pharyngeal pouch (embryology)
In the development of vertebrate animals, pharyngeal or branchial pouches form on the endodermal side between the branchial arches, and pharyngeal grooves (or clefts) form the lateral ecto...
In the development of vertebrate animals, pharyngeal or branchial pouches form on the endodermal side between the branchial arches, and pharyngeal grooves (or clefts) form the lateral ecto...
Pharyngula
In developmental biology, the pharyngula is a stage in embryonic development.
In developmental biology, the pharyngula is a stage in embryonic development.
Placenta
The placenta is an organ that connects the developing fetus to the uterine wall to allow nutrient uptake, waste elimination, and gas exchange via the mother's blood supply.r Placentas are a def...
The placenta is an organ that connects the developing fetus to the uterine wall to allow nutrient uptake, waste elimination, and gas exchange via the mother's blood supply.r Placentas are a def...
Placental cotyledon
In human development, the cotyledons are the approximately 15-30 separations of the desidua basalis of the placenta, separated by placental septa.
In human development, the cotyledons are the approximately 15-30 separations of the desidua basalis of the placenta, separated by placental septa.
Placentation
In biology, placentation refers to the formation, type and structure, or arrangement of placentas.
In biology, placentation refers to the formation, type and structure, or arrangement of placentas.
Placode
A placode is an area of thickening in the embryonic epithelial layer where some organ or structure later develops.
A placode is an area of thickening in the embryonic epithelial layer where some organ or structure later develops.
Plant embryogenesis
Plant embryogenesis is the process that produces a plant embryo from a fertilised ovule by asymmetric cell division and the differentiation of undifferentiated cells into tissues and organs.
Plant embryogenesis is the process that produces a plant embryo from a fertilised ovule by asymmetric cell division and the differentiation of undifferentiated cells into tissues and organs.
Polyembryony
Polyembryony is the phenomenon of two or more embryos developing from a single fertilized egg (in humans, identical twins).
Polyembryony is the phenomenon of two or more embryos developing from a single fertilized egg (in humans, identical twins).
Pontine flexure
The pontine flexure is a bend in the axis of the embryological central nervous system.
The pontine flexure is a bend in the axis of the embryological central nervous system.
Posterior urethral valve
Posterior urethral valve (PUV) disorder is an obstructive developmental anomaly in the urethra and genitourinary system of male newborns.
Posterior urethral valve (PUV) disorder is an obstructive developmental anomaly in the urethra and genitourinary system of male newborns.
Prenatal development
Prenatal or antenatal development is the process in which a human embryo or fetus (or foetus) gestates during pregnancy, from fertilization until birth.
Prenatal or antenatal development is the process in which a human embryo or fetus (or foetus) gestates during pregnancy, from fertilization until birth.
Prenatal development (biology)
Prenatal development is the process in which an immature individual develops before birth.
Prenatal development is the process in which an immature individual develops before birth.
Prenatal testosterone transfer
Prenatal Testosterone Transfer also known as prenatal androgen transfer or prenatal hormone transfer refers to the phenomenon in which testosterone synthesized by a developing male fetus transfe...
Prenatal Testosterone Transfer also known as prenatal androgen transfer or prenatal hormone transfer refers to the phenomenon in which testosterone synthesized by a developing male fetus transfe...
Primary bone
Primary bone is the first bone tissue that appear in embryonic development and in fraction repair.
Primary bone is the first bone tissue that appear in embryonic development and in fraction repair.
Primary interatrial foramen
In the developing heart, the atria initially communicate with each other by an opening between the free edge of the septum primum and the AV cushions, known as the primary interatrial foramen or...
In the developing heart, the atria initially communicate with each other by an opening between the free edge of the septum primum and the AV cushions, known as the primary interatrial foramen or...
Primary interventricular foramen
In human embryology, the primary interventricular foramen is a temporary opening between the developing ventricles of the heart.
In human embryology, the primary interventricular foramen is a temporary opening between the developing ventricles of the heart.
Primary palate
By the fusion of the maxillary and nasal processes in the roof of the stomodeum the primitive palate (or primary palate) is formed, and the olfactory pits extend backward above it.
By the fusion of the maxillary and nasal processes in the roof of the stomodeum the primitive palate (or primary palate) is formed, and the olfactory pits extend backward above it.
Primitive atrium
The primitive atrium is a term used to describe a stage in the embryonic development of the human heart.
The primitive atrium is a term used to describe a stage in the embryonic development of the human heart.
Primitive groove
A shallow groove, the primitive groove, appears on the surface of the primitive streak, and the anterior end of this groove communicates by means of an aperture, the blastophore, with the yolk-sac.
A shallow groove, the primitive groove, appears on the surface of the primitive streak, and the anterior end of this groove communicates by means of an aperture, the blastophore, with the yolk-sac.
Primitive heart tube
The primitive heart tube is the earliest stage of heart development.
The primitive heart tube is the earliest stage of heart development.
Primitive palate
By the fusion of the maxillary and nasal processes in the roof of the stomodeum the primitive palate (or primary palate) is formed, and the olfactory pits extend backward above it.
By the fusion of the maxillary and nasal processes in the roof of the stomodeum the primitive palate (or primary palate) is formed, and the olfactory pits extend backward above it.
Primitive ventricle
The primitive ventricle of the developing heart gives rise to the trabeculated parts of the left and right ventricles.
The primitive ventricle of the developing heart gives rise to the trabeculated parts of the left and right ventricles.
Proctodeum
A proctodeum is the back ectodermal part of an alimentary canal.
A proctodeum is the back ectodermal part of an alimentary canal.
Proembryo
Proembryo, or pro-embryo, is a botanical term that has been used for centuries, to denote the series of cells that are formed after fertilization within the ovule of a flowering plant, bef...
Proembryo, or pro-embryo, is a botanical term that has been used for centuries, to denote the series of cells that are formed after fertilization within the ovule of a flowering plant, bef...
Pronephric duct
The pronephric duct is the predecessor of the Wolffian duct.
The pronephric duct is the predecessor of the Wolffian duct.
Pronephros
Pronephros the most basic of the three excretory organs that develop in vertebrates, corresponding to the first stage of kidney development.
Pronephros the most basic of the three excretory organs that develop in vertebrates, corresponding to the first stage of kidney development.
Respiratory bud
The cephalic part of the laryngo-tracheal tube becomes the larynx, and its next succeeding part the trachea, while from its caudal end two lateral outgrowths, the right and left respiratory buds...
The cephalic part of the laryngo-tracheal tube becomes the larynx, and its next succeeding part the trachea, while from its caudal end two lateral outgrowths, the right and left respiratory buds...
Rhombomere
In the vertebrate embryo, a rhombomere is a transiently divided segment of the developing neural tube, within the hindbrain region (a neuromere) in the area that will eventually become the rhomb...
In the vertebrate embryo, a rhombomere is a transiently divided segment of the developing neural tube, within the hindbrain region (a neuromere) in the area that will eventually become the rhomb...
Rostral neuropore
The rostral neuropore or anterior neuropore is a region corresponding to the opening of the embryonic neural tube in the anterior portion of the prosencephalon.
The rostral neuropore or anterior neuropore is a region corresponding to the opening of the embryonic neural tube in the anterior portion of the prosencephalon.
Sclerotome
A sclerotome is part of a somite, a structure in vertebrate embryonic development.
A sclerotome is part of a somite, a structure in vertebrate embryonic development.
Second pharyngeal arch
The second pharyngeal arch or hyoid arch assists in forming the side and front of the neck.
The second pharyngeal arch or hyoid arch assists in forming the side and front of the neck.
Segmentation gene
A segmentation gene is a gene involved in the early stages of pattern formation that define repeated units (metameres) in a segmented organism, usually the embryo.
A segmentation gene is a gene involved in the early stages of pattern formation that define repeated units (metameres) in a segmented organism, usually the embryo.
Septum intermedium
Endocardial cushions project into the atrial canal, and, meeting in the middle line, unite to form the septum intermedium which divides the canal into two channels, the future right and left atr...
Endocardial cushions project into the atrial canal, and, meeting in the middle line, unite to form the septum intermedium which divides the canal into two channels, the future right and left atr...
Septum primum
In the developing heart, the cavity of the primitive atrium becomes subdivided into right and left chambers by a septum, the septum primum, which grows downward into the cavity.
In the developing heart, the cavity of the primitive atrium becomes subdivided into right and left chambers by a septum, the septum primum, which grows downward into the cavity.
Septum secundum
The septum secundum, semilunar in shape, grows downward from the upper wall of the atrium immediately to the right of the primary septum and ostium secundum.
The septum secundum, semilunar in shape, grows downward from the upper wall of the atrium immediately to the right of the primary septum and ostium secundum.
Septum spurium
During development of the heart, the orifice of the coronary sinus lies obliquely, and is guarded by two halves, the right and left venous valves; above the opening these unite with each other and are...
During development of the heart, the orifice of the coronary sinus lies obliquely, and is guarded by two halves, the right and left venous valves; above the opening these unite with each other and are...
Septum transversum
The septum transversum is a thick mass of cranial mesenchyme that gives rise to parts of the thoracic diaphragm and the ventral mesentery of the foregut in the developed human being.
The septum transversum is a thick mass of cranial mesenchyme that gives rise to parts of the thoracic diaphragm and the ventral mesentery of the foregut in the developed human being.
Sinus tubercle
Sinus tubercle is the proliferation of endoderm induced by the paramesonephric ducts.
Sinus tubercle is the proliferation of endoderm induced by the paramesonephric ducts.
Sinus venosus
The sinus venosus is a large quadrangular cavity which precedes the atrium on the venous side of the chordate heart.
The sinus venosus is a large quadrangular cavity which precedes the atrium on the venous side of the chordate heart.
Somatic embryogenesis
Somatic embryos are mainly produced in vitro and for laboratory purposes, using either solid or liquid nutrient media which contain plant growth regulators.
Somatic embryos are mainly produced in vitro and for laboratory purposes, using either solid or liquid nutrient media which contain plant growth regulators.
Somatopleure
In the anatomy of an embryo, the somatopleure is a structure created during embryogenesis when the lateral mesoderm splits into two layers.
In the anatomy of an embryo, the somatopleure is a structure created during embryogenesis when the lateral mesoderm splits into two layers.
Somatopleuric mesenchyme
In the anatomy of an embryo, the somatopleuric mesenchyme is a structure created during embryogenesis when the lateral mesoderm splits into two layers.
In the anatomy of an embryo, the somatopleuric mesenchyme is a structure created during embryogenesis when the lateral mesoderm splits into two layers.
Somite
A somite is a division of the body of an animal.
A somite is a division of the body of an animal.
Somitogenesis
Somitogenesis is the process by which somites are produced.
Somitogenesis is the process by which somites are produced.
Somitomere
In the developing vertebrate embryo, the somitomeres (or somatomeres) are loose masses of paraxial mesoderm derived cells that form along each side of the neural tube towards the end of th...
In the developing vertebrate embryo, the somitomeres (or somatomeres) are loose masses of paraxial mesoderm derived cells that form along each side of the neural tube towards the end of th...
Spina vestibuli
Below the opening of the orifice of the coronary sinus they fuse to form a triangular thickening—the spina vestibuli.
Below the opening of the orifice of the coronary sinus they fuse to form a triangular thickening—the spina vestibuli.
Splanchnopleure
In the anatomy of an embryo, the splanchnopleure is a structure created during embryogenesis when the lateral mesoderm splits into two layers.
In the anatomy of an embryo, the splanchnopleure is a structure created during embryogenesis when the lateral mesoderm splits into two layers.
Splanchnopleuric mesenchyme
In the anatomy of an embryo, the splanchnopleuric mesenchyme is a structure created during embryogenesis when the lateral mesoderm splits into two layers.
In the anatomy of an embryo, the splanchnopleuric mesenchyme is a structure created during embryogenesis when the lateral mesoderm splits into two layers.
Stigma (anatomy)
A stigma in mammalian reproductive anatomy refers to the area of the ovarian surface where the Graafian follicle will burst through during ovulation and release the ovum.
A stigma in mammalian reproductive anatomy refers to the area of the ovarian surface where the Graafian follicle will burst through during ovulation and release the ovum.
Stomodeum
The stomodeum, also called stomatodeum, is a depression between the brain and the pericardium in an embryo, and is the precursor of the mouth and the anterior lobe of the pituitary gland.
The stomodeum, also called stomatodeum, is a depression between the brain and the pericardium in an embryo, and is the precursor of the mouth and the anterior lobe of the pituitary gland.
Surfactant-albumin ratio
The surfactant-albumin ratio is a test for assessing fetal lung maturity.
The surfactant-albumin ratio is a test for assessing fetal lung maturity.
Syncytiotrophoblast
Syncytiotrophoblasts are multinucleated cells found in the placenta of embryos.
Syncytiotrophoblasts are multinucleated cells found in the placenta of embryos.
Terminologia Embryologica
The Terminologia Embryologica (TE) is a standardized list of words to be used in the description of human embryologic and fetal structures.
The Terminologia Embryologica (TE) is a standardized list of words to be used in the description of human embryologic and fetal structures.
Testis cords
The testis cords are precursors to the rete testis.
The testis cords are precursors to the rete testis.
The Human Embryo: Aristotle and the Arabic and European Traditions
The Human Embryo: Aristotle and the Arabic and European Traditions is a medical book by Professor G.R. Dunstan and published by University of Exeter Press in 1990.
The Human Embryo: Aristotle and the Arabic and European Traditions is a medical book by Professor G.R. Dunstan and published by University of Exeter Press in 1990.
Thyroglossal duct
The thyroglossal duct is an embryological anatomical structure forming an open connection between the initial area of development of the thyroid gland and its final position.
The thyroglossal duct is an embryological anatomical structure forming an open connection between the initial area of development of the thyroid gland and its final position.
Thyroid diverticulum
The thyroid diverticulum is the embryological structure from which thyroid follicular cells derive.
The thyroid diverticulum is the embryological structure from which thyroid follicular cells derive.
Trilaminar blastocyst
A trilaminar embryo is an early stage in the development of triploblastic organisms, which include humans and many other animals.
A trilaminar embryo is an early stage in the development of triploblastic organisms, which include humans and many other animals.
Trilaminar embryo
A trilaminar embryo (or trilaminary blastoderm, or trilaminar germ disk) is an early stage in the development of triploblastic organisms, which include humans and many other animals.
A trilaminar embryo (or trilaminary blastoderm, or trilaminar germ disk) is an early stage in the development of triploblastic organisms, which include humans and many other animals.
Truncus arteriosus (embryology)
The truncus arteriosus and bulbus cordis are divided by the aorticopulmonary septum.
The truncus arteriosus and bulbus cordis are divided by the aorticopulmonary septum.
Tuberculum impar
During the third week of embryological development there appears, immediately behind the ventral ends of the two halves of the mandibular arch, a rounded swelling named the tuberculum impar, wh...
During the third week of embryological development there appears, immediately behind the ventral ends of the two halves of the mandibular arch, a rounded swelling named the tuberculum impar, wh...
Ultimobranchial body
The ultimobranchial body or ultimobranchial gland is a small organ found in the neck region of many animals.
The ultimobranchial body or ultimobranchial gland is a small organ found in the neck region of many animals.
Ultimopharyngeal body
The ultimopharyngeal body or ultimobranchial body or ultimobranchial gland is a small organ found in the neck region of many animals.
The ultimopharyngeal body or ultimobranchial body or ultimobranchial gland is a small organ found in the neck region of many animals.
Umbilical artery
The umbilical artery is a paired artery (with one for each half of the body) that is found in the abdominal and pelvic regions.
The umbilical artery is a paired artery (with one for each half of the body) that is found in the abdominal and pelvic regions.
Umbilical cord
In placental mammals, the umbilical cord (also called the birth cord or funiculus umbilicalis) is the connecting cord from the developing embryo or fetus to the placenta.
In placental mammals, the umbilical cord (also called the birth cord or funiculus umbilicalis) is the connecting cord from the developing embryo or fetus to the placenta.
Umbilical vein
The umbilical vein is a vein present during fetal development that carries oxygenated blood from the placenta to the growing fetus.
The umbilical vein is a vein present during fetal development that carries oxygenated blood from the placenta to the growing fetus.
Urachus
The urachus is a fibrous remnant of the allantois, a canal that drains the urinary bladder of the fetus that joins and runs within the umbilical cord.
The urachus is a fibrous remnant of the allantois, a canal that drains the urinary bladder of the fetus that joins and runs within the umbilical cord.
Urogenital folds
The urogenital folds (or urogenital ridges, or urethral folds) are an embryological structure which give rise to a portion of the external genitalia.
The urogenital folds (or urogenital ridges, or urethral folds) are an embryological structure which give rise to a portion of the external genitalia.
Urogenital sinus
The urogenital sinus (also known as the persistent cloaca) is a part of the human body only present in the development of the urinary and reproductive organs.
The urogenital sinus (also known as the persistent cloaca) is a part of the human body only present in the development of the urinary and reproductive organs.
Vascular remodelling in the embryo
Vascular remodelling is a process which begins at day 21 of human embryogenesis, when an immature heart begins contracting, pushing fluid through the early vasculature.
Vascular remodelling is a process which begins at day 21 of human embryogenesis, when an immature heart begins contracting, pushing fluid through the early vasculature.
Vegetal rotation
Vegetal Rotation is a morphogenetic movement that drives mesendoderm internalization during gastrulation in amphibian embryos.
Vegetal Rotation is a morphogenetic movement that drives mesendoderm internalization during gastrulation in amphibian embryos.
Vitelline circulation
Vitelline circulation refers to the system of blood flowing from the embryo to the yolk sac and back again.
Vitelline circulation refers to the system of blood flowing from the embryo to the yolk sac and back again.
Vitelline duct
In the human embryo, the vitelline duct, also known as the omphalomesenteric duct, is a long narrow tube that joins the yolk-sac to the midgut lumen of the developing fetus.
In the human embryo, the vitelline duct, also known as the omphalomesenteric duct, is a long narrow tube that joins the yolk-sac to the midgut lumen of the developing fetus.
Vitelline membrane
The vitelline membrane is a structure directly adjacent to the outer surface of the plasma membrane of an ovum.
The vitelline membrane is a structure directly adjacent to the outer surface of the plasma membrane of an ovum.
Warkany syndrome
Warkany syndrome 1 is an X-chromosome linked recessive genetic condition originally described by Warkany in 1961 as part of an article on intrauterine growth retardation.
Warkany syndrome 1 is an X-chromosome linked recessive genetic condition originally described by Warkany in 1961 as part of an article on intrauterine growth retardation.
Wharton's jelly
Wharton's jelly (substantia gelatinea funiculi umbilicalis) is a gelatinous substance within the umbilical cord, largely made up of mucopolysaccharides (hyaluronic acid and chondroitin sulfate).
Wharton's jelly (substantia gelatinea funiculi umbilicalis) is a gelatinous substance within the umbilical cord, largely made up of mucopolysaccharides (hyaluronic acid and chondroitin sulfate).
Yolk sac
The yolk sac is a membranous sac attached to an embryo, providing early nourishment in the form of yolk in bony fishes, sharks, reptiles, birds, and primitive mammals.
The yolk sac is a membranous sac attached to an embryo, providing early nourishment in the form of yolk in bony fishes, sharks, reptiles, birds, and primitive mammals.
Zona hatching
Zona hatching is a phenomenon occurring during prenatal development.
Zona hatching is a phenomenon occurring during prenatal development.
Zone of polarizing activity
The Zone of Polarizing Activity (ZPA) is an area of mesenchyme that contains signals which instruct the developing limb bud to form along the anterior/posterior axis.
The Zone of Polarizing Activity (ZPA) is an area of mesenchyme that contains signals which instruct the developing limb bud to form along the anterior/posterior axis.