Term
| How does the Intraembryonic Coelom form? |
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Definition
| begins when spaces coalesce within the lateral mesoderm and form a horseshoe-shaped space that opens into the chorionic cavity (extraembryonic coelom) on the right and left side. |
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Term
| What does the intraembryonic coelom provide for the body? |
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Definition
| The needed room for growth of various organs |
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Term
| What cavities are derived from the intraembryonic coelom? |
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Definition
| Pericardial, pleural and peritoneal cavities. Two partitions pleuropericardial membranes and the diaphragm. |
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Term
| What membranes separate the pericardial cavity from the pleural cavities? |
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Definition
| Paired pleuropericardial membranes. sheets of somatic mesoderm |
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Term
| What are the 4 sources for the diaphragm and what does it separate? |
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Definition
| Septum transversum, Paired Pleroperitoneal membranes, Dorsal mesentery of the esophagus, Body wall. Separates Pleural Cavities from teh peritoneal cavity. |
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Term
| What is the Septum Transversum? |
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Definition
| Is a thick mass of mesoderm located between the primitive heart tube and teh developing liver. Primordium of central tendon of the diaphragm in the adult. |
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Term
| What do the dorsal mesenteries of the esophagus develop from? |
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Definition
| Myoblasts invade this mesentery to form the crura of the diaphragm in the adult |
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Term
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Definition
| contributes muscle to the peripheral portions of the definitive diaphragm. |
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Term
| How does the position of the diaphragm chagne during development? |
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Definition
| Week 8 there is a descent of he diaphragm to L1 because of the rapid growth of the neural tube. Phrenic nerves carried with it which explains their long length in the adult. |
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Term
| What cervical nerves does the phrenic nerve originate from? |
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Definition
| C3,C4,C5. These pass through the pleuropericardial membranes. |
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Term
| What is a congenital diaphragmatic hernia? |
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Definition
| herniation of abdominal contents into the pleural cavity. Caused by failure of pleuroperitoneal membrane to develop or fuse with the other components of the diaphragm. common on left side. causes pulmonary hypoplasia. unusually flat abdomen, breathlessness, cyanosis. |
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Term
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Definition
| Herniation of stomach through the esophageal hiatus into the pleural cavity. Abnormally large esophaeal hiatus. Renders esophagogastric sphincter incompetent so stomach contents reflux into the esophagus. vomitting when laid on back after feeding. |
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