Podcast
Questions and Answers
What does a urachal fistula indicate?
What does a urachal fistula indicate?
- Absence of urachal structures
- Development of abnormal urinary connections
- Persistence of the distal part of the urachus
- Persistence of the whole urachus (correct)
Which structure is primarily responsible for embryonic nutrition before placental function begins?
Which structure is primarily responsible for embryonic nutrition before placental function begins?
- Allantois
- Amniotic fluid
- Umbilical cord
- Yolk sac (correct)
Which of the following best describes the structure of the umbilical cord?
Which of the following best describes the structure of the umbilical cord?
- Covered with an amniotic sheath formed from extra-embryonic mesoderm (correct)
- Covered by a thick fibrous layer with no underlying structures
- Contains only the definitive yolk sac
- Includes only two umbilical arteries
What physiological change occurs in the umbilical cord during the 6th to 10th week of development?
What physiological change occurs in the umbilical cord during the 6th to 10th week of development?
What is the significance of cells migrating from the gut to the gonads?
What is the significance of cells migrating from the gut to the gonads?
What does the left umbilical vein develop into after birth?
What does the left umbilical vein develop into after birth?
What type of umbilical cord attachment is characterized by being attached to the margin of the placenta?
What type of umbilical cord attachment is characterized by being attached to the margin of the placenta?
Which type of true knot in the umbilical cord affects placental circulation?
Which type of true knot in the umbilical cord affects placental circulation?
What structure does the chorion frondosum contribute to?
What structure does the chorion frondosum contribute to?
Which type of villi is characterized by containing fetal blood vessels?
Which type of villi is characterized by containing fetal blood vessels?
What is the fate of the chorion leave?
What is the fate of the chorion leave?
What can a long umbilical cord lead to during pregnancy?
What can a long umbilical cord lead to during pregnancy?
Which anatomical structures are involved in the formation of primary villi?
Which anatomical structures are involved in the formation of primary villi?
What is the main source of amniotic fluid in the amniotic cavity?
What is the main source of amniotic fluid in the amniotic cavity?
During which week does the amniotic cavity completely surround the embryo?
During which week does the amniotic cavity completely surround the embryo?
What characterizes oligohydramnios?
What characterizes oligohydramnios?
Which of the following is NOT a function of the amniotic cavity?
Which of the following is NOT a function of the amniotic cavity?
What is one cause of polyhydramnios?
What is one cause of polyhydramnios?
What percentage of the amniotic fluid is composed of water?
What percentage of the amniotic fluid is composed of water?
What is a potential consequence of prolonged oligohydramnios?
What is a potential consequence of prolonged oligohydramnios?
Which structure forms the roof of the amniotic cavity during its development?
Which structure forms the roof of the amniotic cavity during its development?
What is the weight of the placenta in relation to the baby?
What is the weight of the placenta in relation to the baby?
Which structure forms the fetal part of the placenta?
Which structure forms the fetal part of the placenta?
How does the placenta facilitate respiratory function for the fetus?
How does the placenta facilitate respiratory function for the fetus?
What is a key characteristic of the maternal surface of the placenta?
What is a key characteristic of the maternal surface of the placenta?
At what week of pregnancy do changes in the placental barrier structure occur?
At what week of pregnancy do changes in the placental barrier structure occur?
Which hormone is secreted by the placenta to maintain the corpus luteum?
Which hormone is secreted by the placenta to maintain the corpus luteum?
What condition is known as accessory placenta?
What condition is known as accessory placenta?
Which function of the placenta involves the elimination of waste products from the fetus?
Which function of the placenta involves the elimination of waste products from the fetus?
What is the function of the allantois in embryonic development?
What is the function of the allantois in embryonic development?
Which structure becomes incorporated inside the embryo during the 4th week?
Which structure becomes incorporated inside the embryo during the 4th week?
What happens to the extra-embryonic part of the allantois?
What happens to the extra-embryonic part of the allantois?
What is a common feature of Meckel’s diverticulum?
What is a common feature of Meckel’s diverticulum?
Which of the following options describes a vitelline cyst?
Which of the following options describes a vitelline cyst?
What can occur if the vitelline duct is obliterated but not degenerated?
What can occur if the vitelline duct is obliterated but not degenerated?
What marks the transition from the primary yolk sac to the second yolk sac?
What marks the transition from the primary yolk sac to the second yolk sac?
What does the distal part of the urachus become after its development?
What does the distal part of the urachus become after its development?
What is a characteristic of placenta percreta?
What is a characteristic of placenta percreta?
Which type of twins arises from the fertilization of two separate eggs?
Which type of twins arises from the fertilization of two separate eggs?
What type of twin formation occurs at the bilaminar stage of development?
What type of twin formation occurs at the bilaminar stage of development?
Which of the following is not a characteristic of monozygotic twins?
Which of the following is not a characteristic of monozygotic twins?
What is the primary cause of conjoined twins?
What is the primary cause of conjoined twins?
At which developmental stage do diamniotic dichorionic twins form?
At which developmental stage do diamniotic dichorionic twins form?
What percentage of twin births are typically dizygotic?
What percentage of twin births are typically dizygotic?
Which of the following characteristics applies to dizygotic twins?
Which of the following characteristics applies to dizygotic twins?
What is a primary cause of oligohydramnios?
What is a primary cause of oligohydramnios?
Which component is primarily responsible for the maintenance of electrolyte balance in the amniotic cavity?
Which component is primarily responsible for the maintenance of electrolyte balance in the amniotic cavity?
During which week of development does the amniotic cavity fully encapsulate the embryo?
During which week of development does the amniotic cavity fully encapsulate the embryo?
What is the main composition of amniotic fluid?
What is the main composition of amniotic fluid?
What is a common fetal anomaly associated with oligohydramnios?
What is a common fetal anomaly associated with oligohydramnios?
What source primarily contributes to the production of amniotic fluid at later stages of fetal development?
What source primarily contributes to the production of amniotic fluid at later stages of fetal development?
What is the primary role of the yolk sac before the function of the liver begins?
What is the primary role of the yolk sac before the function of the liver begins?
Which structure is formed from the allantois after birth?
Which structure is formed from the allantois after birth?
What is the fate of the intra-embryonic part of the allantois?
What is the fate of the intra-embryonic part of the allantois?
During which week does physiological hernia occur as a normal developmental change?
During which week does physiological hernia occur as a normal developmental change?
Which anomaly is characterized by the persistence of the whole vitelline duct?
Which anomaly is characterized by the persistence of the whole vitelline duct?
What is the correct description of the primitive umbilical cord's diameter?
What is the correct description of the primitive umbilical cord's diameter?
During which week does the second yolk sac begin to communicate with the amniotic cavity?
During which week does the second yolk sac begin to communicate with the amniotic cavity?
What contributes to the formation of Meckel’s diverticulum?
What contributes to the formation of Meckel’s diverticulum?
What component is NOT part of the structure of the primitive umbilical cord?
What component is NOT part of the structure of the primitive umbilical cord?
Which structure is formed from the medial part of the allantois?
Which structure is formed from the medial part of the allantois?
What remains connected to the definitive yolk sac by the vitello-intestinal duct?
What remains connected to the definitive yolk sac by the vitello-intestinal duct?
In which population is Meckel’s diverticulum more prevalent?
In which population is Meckel’s diverticulum more prevalent?
What defines the roof of the primary yolk sac?
What defines the roof of the primary yolk sac?
What is the primary reason for the occurrence of conjoined twins?
What is the primary reason for the occurrence of conjoined twins?
At which stage do diamniotic monochorionic twins develop?
At which stage do diamniotic monochorionic twins develop?
Which type of twins is characterized by being genetically identical?
Which type of twins is characterized by being genetically identical?
What configuration characterizes placenta percreta?
What configuration characterizes placenta percreta?
What percentage of twin births is typically attributed to dizygotic formation?
What percentage of twin births is typically attributed to dizygotic formation?
Which statement about the appearance of monozygotic twins is true?
Which statement about the appearance of monozygotic twins is true?
What defines the fetal membranes configuration for diamniotic dichorionic twins?
What defines the fetal membranes configuration for diamniotic dichorionic twins?
What is a potential site for fusion in conjoined twins?
What is a potential site for fusion in conjoined twins?
What is the fate of the chorion frondosum during development?
What is the fate of the chorion frondosum during development?
Which type of umbilical cord attachment is characterized by the cord being attached away from the placenta?
Which type of umbilical cord attachment is characterized by the cord being attached away from the placenta?
What is a potential consequence of having a true knot in the umbilical cord?
What is a potential consequence of having a true knot in the umbilical cord?
What structure is primarily involved in the formation of tertiary villi?
What structure is primarily involved in the formation of tertiary villi?
Which type of anomaly is characterized by a short umbilical cord?
Which type of anomaly is characterized by a short umbilical cord?
In the context of chorionic development, which type is destined to degenerate?
In the context of chorionic development, which type is destined to degenerate?
How do absorbing villi function within the placenta?
How do absorbing villi function within the placenta?
What results from the degeneration of the definitive yolk sac?
What results from the degeneration of the definitive yolk sac?
What is the primary protective function of the placenta during pregnancy?
What is the primary protective function of the placenta during pregnancy?
Which surface of the placenta exhibits a characteristic cobblestone appearance?
Which surface of the placenta exhibits a characteristic cobblestone appearance?
What happens to the structure of the placental barrier after the 20th week of pregnancy?
What happens to the structure of the placental barrier after the 20th week of pregnancy?
Which hormone does the placenta primarily secrete to stimulate milk formation during pregnancy?
Which hormone does the placenta primarily secrete to stimulate milk formation during pregnancy?
Which characteristic defines the weight of the placenta in relation to the baby's weight?
Which characteristic defines the weight of the placenta in relation to the baby's weight?
What type of placenta anomaly is characterized by an accessory placenta?
What type of placenta anomaly is characterized by an accessory placenta?
What is the main function of the placental barrier during fetal development?
What is the main function of the placental barrier during fetal development?
Which hormone is primarily responsible for maintaining the corpus luteum in early pregnancy?
Which hormone is primarily responsible for maintaining the corpus luteum in early pregnancy?
What is the result of persistence of the entire urachus in embryonic development?
What is the result of persistence of the entire urachus in embryonic development?
During which developmental week does the umbilical cord begin to take shape as a connecting stalk?
During which developmental week does the umbilical cord begin to take shape as a connecting stalk?
What are the two primary blood vessels found in a typical umbilical cord?
What are the two primary blood vessels found in a typical umbilical cord?
What embryonic structure contributes to the formation of the median umbilical ligament after birth?
What embryonic structure contributes to the formation of the median umbilical ligament after birth?
What life-supporting function does the yolk sac provide before the liver takes over?
What life-supporting function does the yolk sac provide before the liver takes over?
What anatomical structure do the 2 umbilical arteries become after development?
What anatomical structure do the 2 umbilical arteries become after development?
What distinguishes a true knot from a false knot in the umbilical cord?
What distinguishes a true knot from a false knot in the umbilical cord?
During which stage are tertiary villi formed?
During which stage are tertiary villi formed?
What condition is characterized by the persistent physiological hernia after the 10th week?
What condition is characterized by the persistent physiological hernia after the 10th week?
What type of umbilical cord attachment is identified by being attached away from the placenta?
What type of umbilical cord attachment is identified by being attached away from the placenta?
What complications can arise from a short umbilical cord?
What complications can arise from a short umbilical cord?
What are the primary components that make up primary villi?
What are the primary components that make up primary villi?
What are the different shapes of the placenta associated with placenta percreta?
What are the different shapes of the placenta associated with placenta percreta?
What is the genetic difference between dizygotic and monozygotic twins?
What is the genetic difference between dizygotic and monozygotic twins?
What is one of the key characteristics of conjoined twins?
What is one of the key characteristics of conjoined twins?
How does the incidence of dizygotic twins compare to that of monozygotic twins?
How does the incidence of dizygotic twins compare to that of monozygotic twins?
How many zygotes are involved in the formation of dizygotic twins?
How many zygotes are involved in the formation of dizygotic twins?
Describe the process of amniotic fluid circulation in the amniotic cavity.
Describe the process of amniotic fluid circulation in the amniotic cavity.
What are two potential causes of oligohydramnios?
What are two potential causes of oligohydramnios?
Explain the significance of the amniotic cavity in fetal development.
Explain the significance of the amniotic cavity in fetal development.
What is the maximum volume of amniotic fluid typically present at birth?
What is the maximum volume of amniotic fluid typically present at birth?
Identify one fetal and one maternal cause of polyhydramnios.
Identify one fetal and one maternal cause of polyhydramnios.
What characterizes the composition of amniotic fluid?
What characterizes the composition of amniotic fluid?
What is one of the main developmental structures that form the floor of the amniotic cavity?
What is one of the main developmental structures that form the floor of the amniotic cavity?
What effect does the rupture of the amniotic sac have during labor?
What effect does the rupture of the amniotic sac have during labor?
What anatomical structures form the floor and roof of the primary yolk sac during embryonic development?
What anatomical structures form the floor and roof of the primary yolk sac during embryonic development?
Describe the fate of the intra-embryonic and extra-embryonic parts of the allantois.
Describe the fate of the intra-embryonic and extra-embryonic parts of the allantois.
What anomalies are associated with the persistence of the vitelline duct?
What anomalies are associated with the persistence of the vitelline duct?
What structure is formed from the proximal part of the vitelline duct, and what percentage of people does it affect?
What structure is formed from the proximal part of the vitelline duct, and what percentage of people does it affect?
In what manner does the second yolk sac communicate with the amniotic cavity?
In what manner does the second yolk sac communicate with the amniotic cavity?
What key role does the definitive yolk sac play in embryonic development after folding occurs?
What key role does the definitive yolk sac play in embryonic development after folding occurs?
What is the anatomical significance of the vitello-intestinal duct?
What is the anatomical significance of the vitello-intestinal duct?
What occurs during the 4th week of embryonic development concerning the yolk sac?
What occurs during the 4th week of embryonic development concerning the yolk sac?
What is the thickness and weight of the placenta as compared to the baby's weight?
What is the thickness and weight of the placenta as compared to the baby's weight?
Describe the appearance of the maternal surface of the placenta.
Describe the appearance of the maternal surface of the placenta.
What structures form the placental barrier before the 20th week of pregnancy?
What structures form the placental barrier before the 20th week of pregnancy?
What is the primary function of the placenta in terms of gas exchange for the fetus?
What is the primary function of the placenta in terms of gas exchange for the fetus?
Which hormones are secreted by the placenta to maintain pregnancy and support fetal development?
Which hormones are secreted by the placenta to maintain pregnancy and support fetal development?
What characterizes placenta previa as an anomaly?
What characterizes placenta previa as an anomaly?
How does the thickness of the placenta change throughout pregnancy?
How does the thickness of the placenta change throughout pregnancy?
Define placenta succenturiata and its significance.
Define placenta succenturiata and its significance.
What forms the floor of the primary yolk sac during the second week of development?
What forms the floor of the primary yolk sac during the second week of development?
How does the secondary yolk sac communicate with the amniotic cavity?
How does the secondary yolk sac communicate with the amniotic cavity?
What are the features of Meckel's diverticulum?
What are the features of Meckel's diverticulum?
What happens to the extra-embryonic portion of the allantois during development?
What happens to the extra-embryonic portion of the allantois during development?
What structures remain connected by the vitello-intestinal duct?
What structures remain connected by the vitello-intestinal duct?
What anomaly occurs due to the persistence of the distal part of the urachus?
What anomaly occurs due to the persistence of the distal part of the urachus?
What causes the formation of a vitelline fistula?
What causes the formation of a vitelline fistula?
What are the primary sources of amniotic fluid in the amniotic cavity?
What are the primary sources of amniotic fluid in the amniotic cavity?
How does excess amniotic fluid affect the fetus during development?
How does excess amniotic fluid affect the fetus during development?
During which week of development does the amniotic cavity begin to communicate with the yolk sac?
During which week of development does the amniotic cavity begin to communicate with the yolk sac?
What are some of the key functions of the amniotic cavity?
What are some of the key functions of the amniotic cavity?
What is oligohydramnios and what are its possible causes?
What is oligohydramnios and what are its possible causes?
What happens to the amniotic fluid when the fetus swallows it?
What happens to the amniotic fluid when the fetus swallows it?
What is the characteristic composition of amniotic fluid at birth?
What is the characteristic composition of amniotic fluid at birth?
What role does the amniotic fluid play during labor?
What role does the amniotic fluid play during labor?
What is the clinical significance of a persistent urachal diverticulum?
What is the clinical significance of a persistent urachal diverticulum?
Describe the role of the yolk sac before the liver takes over hematopoiesis.
Describe the role of the yolk sac before the liver takes over hematopoiesis.
What are the main components of the primitive umbilical cord?
What are the main components of the primitive umbilical cord?
What anatomical changes occur in the umbilical cord structure during the 4th week of development?
What anatomical changes occur in the umbilical cord structure during the 4th week of development?
How does the allantois contribute to fetal development after birth?
How does the allantois contribute to fetal development after birth?
What are the consequences of a true knot in the umbilical cord?
What are the consequences of a true knot in the umbilical cord?
Describe the role of anchoring villi in embryonic development.
Describe the role of anchoring villi in embryonic development.
Explain the difference between chorion leave and chorion frondosum.
Explain the difference between chorion leave and chorion frondosum.
What happens to the umbilical vein after birth?
What happens to the umbilical vein after birth?
How can the length of the umbilical cord affect pregnancy outcomes?
How can the length of the umbilical cord affect pregnancy outcomes?
What are secondary villi, and what additional structure do they form?
What are secondary villi, and what additional structure do they form?
What is exomphalos, and when does it occur during development?
What is exomphalos, and when does it occur during development?
Identify the types of umbilical cord attachment and their characteristics.
Identify the types of umbilical cord attachment and their characteristics.
What is the characteristic shape of placenta percreta?
What is the characteristic shape of placenta percreta?
What are the two types of twins based on their formation?
What are the two types of twins based on their formation?
What is the genetic characteristic of monozygotic twins?
What is the genetic characteristic of monozygotic twins?
During which developmental stage do diamniotic dichorionic twins form?
During which developmental stage do diamniotic dichorionic twins form?
What causes conjoined twins to occur?
What causes conjoined twins to occur?
What is the incidence rate of dizygotic twins compared to monozygotic twins?
What is the incidence rate of dizygotic twins compared to monozygotic twins?
What are the different types of twin configurations during pregnancy?
What are the different types of twin configurations during pregnancy?
Which type of twins may fuse at the dorsal surface?
Which type of twins may fuse at the dorsal surface?
What are the two main parts of the placenta and which structures form them?
What are the two main parts of the placenta and which structures form them?
Describe the shape and dimensions of the placenta.
Describe the shape and dimensions of the placenta.
What is the placental barrier, and how does its structure change after the 20th week of pregnancy?
What is the placental barrier, and how does its structure change after the 20th week of pregnancy?
What are the primary functions of the placenta?
What are the primary functions of the placenta?
Which hormone secreted by the placenta is responsible for maintaining the corpus luteum during the first four months of pregnancy?
Which hormone secreted by the placenta is responsible for maintaining the corpus luteum during the first four months of pregnancy?
What is placenta previa, and how does it differ from a succenturiate placenta?
What is placenta previa, and how does it differ from a succenturiate placenta?
How does the placenta facilitate gas exchange for the fetus?
How does the placenta facilitate gas exchange for the fetus?
What is the normal weight of the placenta in relation to fetal weight?
What is the normal weight of the placenta in relation to fetal weight?
Flashcards
Amniotic Cavity
Amniotic Cavity
The fluid-filled space that surrounds the developing embryo.
Amniotic Fluid
Amniotic Fluid
The fluid inside the amniotic cavity that cushions and protects the developing fetus.
Amnioblasts
Amnioblasts
The cells that line the amniotic cavity and contribute to the production of amniotic fluid.
Oligohydramnios
Oligohydramnios
Signup and view all the flashcards
Polyhydramnios
Polyhydramnios
Signup and view all the flashcards
Fetal Kidneys
Fetal Kidneys
Signup and view all the flashcards
Fetal Adhesion
Fetal Adhesion
Signup and view all the flashcards
Rupture of Membranes
Rupture of Membranes
Signup and view all the flashcards
Primary Yolk Sac
Primary Yolk Sac
Signup and view all the flashcards
Secondary Yolk Sac
Secondary Yolk Sac
Signup and view all the flashcards
Yolk Sac Incorporation
Yolk Sac Incorporation
Signup and view all the flashcards
Vitelline Duct
Vitelline Duct
Signup and view all the flashcards
Vitelline Duct Anomalies
Vitelline Duct Anomalies
Signup and view all the flashcards
Meckel's Diverticulum
Meckel's Diverticulum
Signup and view all the flashcards
Allantois
Allantois
Signup and view all the flashcards
Allantois Fate
Allantois Fate
Signup and view all the flashcards
Urachal diverticulum
Urachal diverticulum
Signup and view all the flashcards
Urachal fistula
Urachal fistula
Signup and view all the flashcards
Umbilical cord
Umbilical cord
Signup and view all the flashcards
Wharton's jelly
Wharton's jelly
Signup and view all the flashcards
Physiological hernia
Physiological hernia
Signup and view all the flashcards
Eccentric Umbilical Cord Attachment
Eccentric Umbilical Cord Attachment
Signup and view all the flashcards
Marginal Umbilical Cord Attachment
Marginal Umbilical Cord Attachment
Signup and view all the flashcards
Abnormal Umbilical Cord Number
Abnormal Umbilical Cord Number
Signup and view all the flashcards
Vilamentous Umbilical Cord Attachment
Vilamentous Umbilical Cord Attachment
Signup and view all the flashcards
False Knot in the Umbilical Cord
False Knot in the Umbilical Cord
Signup and view all the flashcards
True Knot in the Umbilical Cord
True Knot in the Umbilical Cord
Signup and view all the flashcards
Long Umbilical Cord
Long Umbilical Cord
Signup and view all the flashcards
Short Umbilical Cord
Short Umbilical Cord
Signup and view all the flashcards
Dizygotic Twins
Dizygotic Twins
Signup and view all the flashcards
Monozygotic Twins
Monozygotic Twins
Signup and view all the flashcards
Monoamniotic Monochorionic Twins
Monoamniotic Monochorionic Twins
Signup and view all the flashcards
Diamniotic Monochorionic Twins
Diamniotic Monochorionic Twins
Signup and view all the flashcards
Diamniotic Dichorionic Twins
Diamniotic Dichorionic Twins
Signup and view all the flashcards
Conjoined Twins
Conjoined Twins
Signup and view all the flashcards
Placenta Percreta
Placenta Percreta
Signup and view all the flashcards
Twins
Twins
Signup and view all the flashcards
Fetal Part of Placenta
Fetal Part of Placenta
Signup and view all the flashcards
Maternal Part of Placenta
Maternal Part of Placenta
Signup and view all the flashcards
What is the placenta?
What is the placenta?
Signup and view all the flashcards
What is the Placental Barrier?
What is the Placental Barrier?
Signup and view all the flashcards
How Does the Placental Barrier Change During Pregnancy?
How Does the Placental Barrier Change During Pregnancy?
Signup and view all the flashcards
What is the Protective Function of the Placenta?
What is the Protective Function of the Placenta?
Signup and view all the flashcards
What is the Respiratory Function of the Placenta?
What is the Respiratory Function of the Placenta?
Signup and view all the flashcards
What is the Excretory Function of the Placenta?
What is the Excretory Function of the Placenta?
Signup and view all the flashcards
What is the amniotic cavity?
What is the amniotic cavity?
Signup and view all the flashcards
What is amniotic fluid?
What is amniotic fluid?
Signup and view all the flashcards
What is rupture of membranes?
What is rupture of membranes?
Signup and view all the flashcards
What is oligohydramnios?
What is oligohydramnios?
Signup and view all the flashcards
What is polyhydramnios?
What is polyhydramnios?
Signup and view all the flashcards
What are the main functions of amniotic fluid?
What are the main functions of amniotic fluid?
Signup and view all the flashcards
What is rupture of membranes?
What is rupture of membranes?
Signup and view all the flashcards
What is a premature rupture of membranes?
What is a premature rupture of membranes?
Signup and view all the flashcards
What is the yolk sac?
What is the yolk sac?
Signup and view all the flashcards
What is the vitelline duct?
What is the vitelline duct?
Signup and view all the flashcards
What is Meckel's diverticulum?
What is Meckel's diverticulum?
Signup and view all the flashcards
What is the allantois?
What is the allantois?
Signup and view all the flashcards
What is the urachus?
What is the urachus?
Signup and view all the flashcards
What are urachal anomalies?
What are urachal anomalies?
Signup and view all the flashcards
What is a vitelline band?
What is a vitelline band?
Signup and view all the flashcards
What is a vitelline fistula?
What is a vitelline fistula?
Signup and view all the flashcards
Yolk sac
Yolk sac
Signup and view all the flashcards
Primitive umbilical cord
Primitive umbilical cord
Signup and view all the flashcards
What is the normal composition of the umbilical cord?
What is the normal composition of the umbilical cord?
Signup and view all the flashcards
What happens to the umbilical cord after birth?
What happens to the umbilical cord after birth?
Signup and view all the flashcards
What are eccentric and marginal umbilical cord attachments?
What are eccentric and marginal umbilical cord attachments?
Signup and view all the flashcards
What is the difference between false and true knots in the umbilical cord?
What is the difference between false and true knots in the umbilical cord?
Signup and view all the flashcards
What are the potential risks of a long or short umbilical cord?
What are the potential risks of a long or short umbilical cord?
Signup and view all the flashcards
What is exomphalus or omphalocele?
What is exomphalus or omphalocele?
Signup and view all the flashcards
What are the different fates of chorion frondosum and chorion leave?
What are the different fates of chorion frondosum and chorion leave?
Signup and view all the flashcards
What are the stages of chorion development?
What are the stages of chorion development?
Signup and view all the flashcards
What causes Conjoined Twins?
What causes Conjoined Twins?
Signup and view all the flashcards
What causes Monozygotic Twins?
What causes Monozygotic Twins?
Signup and view all the flashcards
What are the parts of the placenta?
What are the parts of the placenta?
Signup and view all the flashcards
What is the macroscopic structure of the placenta?
What is the macroscopic structure of the placenta?
Signup and view all the flashcards
What are the surfaces of the placenta?
What are the surfaces of the placenta?
Signup and view all the flashcards
What is the primary yolk sac?
What is the primary yolk sac?
Signup and view all the flashcards
What is the secondary yolk sac?
What is the secondary yolk sac?
Signup and view all the flashcards
What is yolk sac incorporation?
What is yolk sac incorporation?
Signup and view all the flashcards
Urachus
Urachus
Signup and view all the flashcards
Exomphalus or Omphalocele
Exomphalus or Omphalocele
Signup and view all the flashcards
Chorion frondosum
Chorion frondosum
Signup and view all the flashcards
Umbilical Vessels
Umbilical Vessels
Signup and view all the flashcards
Exomphalus (Omphalocele)
Exomphalus (Omphalocele)
Signup and view all the flashcards
Chorion Laeve
Chorion Laeve
Signup and view all the flashcards
False Knot
False Knot
Signup and view all the flashcards
Describe the macroscopic structure of the placenta.
Describe the macroscopic structure of the placenta.
Signup and view all the flashcards
Macroscopic Structure of the Placenta
Macroscopic Structure of the Placenta
Signup and view all the flashcards
Amniotic fluid circulation
Amniotic fluid circulation
Signup and view all the flashcards
Yolk sac anomalies
Yolk sac anomalies
Signup and view all the flashcards
Placental Barrier
Placental Barrier
Signup and view all the flashcards
Human Chorionic Gonadotropin (hCG)
Human Chorionic Gonadotropin (hCG)
Signup and view all the flashcards
Progesterone
Progesterone
Signup and view all the flashcards
Estrogen
Estrogen
Signup and view all the flashcards
Relaxin
Relaxin
Signup and view all the flashcards
Placenta Previa
Placenta Previa
Signup and view all the flashcards
Study Notes
Fetal Membranes & Twins
- Fetal membranes surround and protect the developing embryo/fetus, providing a protective environment and allowing for gas exchange, waste removal, and nutrition.
- The amniotic cavity is filled with amniotic fluid, which cushions the embryo and prevents it from adhering to the membranes.
- Amniotic fluid is mostly water, with a small percentage of organic and inorganic salts, and fetal epithelium.
- Amniotic fluid originates in amnioblasts, the placenta, and the fetal kidney.
- Excess amniotic fluid is absorbed back into the bloodstream, via the fetal kidneys, and waste products are removed by the maternal blood; fetus can also swallow some of the amniotic fluid.
Amniotic Fluid
- Definition: Fluid that fills the amniotic cavity, surrounding the embryo.
- Amount: Approximately one liter at birth.
- Sources: Amnioblasts, placenta, and fetal kidneys.
- Structure: Primarily water; also contains inorganic salts, organics, and fetal cells.
- Circulation: Amniotic fluid is produced and absorbed by the fetus and placenta. Excess fluid is transported via the urinary system back to the amniotic cavity and waste products are returned to maternal blood; fetus can also swallow some of the fluid.
Oligohydramnios
- Definition: Amniotic fluid volume less than 0.5 liters.
- Causes: Placental insufficiency, renal agenesis, urinary tract obstruction.
- Character: Fetal adhesions, other abnormalities.
Polyhydramnios
- Definition: Amniotic fluid volume greater than 2 liters.
- Causes: Idiopathic (most common), fetal issues (esophageal atresia), or maternal issues (diabetes).
- Character: Maternal and fetal distress, possible true knots in the umbilical cord.
Yolk Sac
- Definition: A cavity related to the ventral surface of the embryo.
- Development: Formed during the second week, with a floor formed by the Heuser's membrane and a roof formed by the hypoblast. During the third week, it communicates with the amniotic cavity via the neurenteric canal. During the fourth week, some of the yolk sac is incorporated into the developing gut and some becomes the definitive yolk sac. Both are connected by the vitello-intestinal duct.
Vitelline Duct Anomalies
- Vitelline band: The vitelline duct is obliterated but not completely degraded.
- Vitelline fistula: Persistence of the entire vitelline duct.
- Vitelline sinus: Persistence of the distal portion of the vitelline duct.
- Vitelline cyst: Persistence of the middle portion of the vitelline duct.
- Meckel’s diverticulum: Persistence of the proximal vitelline duct (occurs twice as commonly in males). It is approximately two inches long and is positioned a few feet from the ileocecal junction; it can have ectopic gastric or pancreatic tissue.
Allantois
- Definition: Extension from the caudal part of the yolk sac into the umbilical cord.
- Fate: Extra-embryonic part degenerates, while the intra-embryonic part becomes the urachus; the medial part forms the apex of the urinary bladder, and the distal part of the urachus forms the median umbilical ligament.
- Anomalies: Persistence of the distal part (urachal sinus), middle part (urachal cyst), or the whole urachus (urachal fistula). A urachal diverticulum is the persistence of the proximal part of the urachus.
Umbilical Cord
- Development: Forms during the second week as a connecting stalk and becomes positioned ventrally during the fourth week.
- Structure: Primitive umbilical cord is ~50cm long and ~1cm in diameter and is composed of extra-embryonic mesoderm and the allantois. The umbilical cord contains umbilical vessels (2 arteries & 1 vein). Wharton's jelly surrounds the blood vessels.
- Changes after birth: Allantois forms umbilical scar; two arteries are the left umbilical arteries; and the left umbilical vein is a ligament running to the liver.
- Anomalies: Abnormal attachments to the placenta, number of vessels (2 or 3), and knots (true vs. false). Short or long cord and ectopic hernia (omphalocele). Variations in structure are possible.
Chorion
- Structure: Syncytiotrophoblast, cytotrophoblast, and somatic extra-embryonic mesoderm.
- Development: Primary villi develop from the syncytiotrophoblast and cytotrophoblast; Secondary villi develop by the addition of somatic extraembryonic mesoderm; tertiary villi have fetal blood vessels.
- Types & Fate: Chorion leaves, chorion frondosum (fetal side of the placenta).
- Function: Anchoring villi fix the embryonic sac to the endometrium; absorbing villi exchange gas and materials between the fetal and maternal blood.
Placenta
- Parts: Fetal part (chorion frondosum) and maternal part (Decidua basalis).
- Structure: Macroscopic structure is discoid, 20cm in diameter, 2cm thick and one-sixth of the fetal weight, with a cobblestone maternal surface and smooth fetal surface with umbilical cord.
- Microscopic structure: Before 20th week, there are syncytiotrohpblast, cytotrophoblast & extra-embryonic mesoderm & fetal blood vessel. After 20th week, there are syncytiotrohpblast, extra-embryonic mesoderm & fetal blood vessel. Late in pregnancy, there are syncytiotrohpblast and fetal blood vessel.
- Function: Gas exchange, nutrient transport, waste removal, and hormone secretion.
Placental anomalies
- Placenta succentriata: Accessory placenta.
- Placenta previa: Chorionic villi penetrate the myometrium of the uterine wall to surrounding organs.
- Placenta percreta: The most severe form of the abnormal placenta previa in which the villi penetrate completely through the uterine wall, or endometrium (this is a more specific term).
- Number anomalies: Abnormal number or abnormal placement of the placenta. Bipartite, zonary, irregular, or tripartite are terms used to describe variations in placental structure.
Twins
- Definition: Delivery of more than one embryo.
- Causes: Hereditary or medical (administration of exogenous gonadotropins).
- Types: Dizygotic and monozygotic.
- Dizygotic: Two oocytes are fertilized by two sperm- the two zygotes are viable and non-identical.
- Monozygotic: One oocyte is fertilized by one sperm that splits to two zygotes. The zygotes are viable and genetically identical.
- Conjoined Twins: Occur in monozygotic twins; the twins fuse at various stages of development and can fuse at the head, thorax, ventral surface or dorsal surface- this results in various degrees and locations of fusion.
- Classification of monozygotic twins: Diamniotic-dichorionic, diamniotic-monochorionic, or monoamniotic-monochorionic, depending on the stage of separation.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
