Term
What signalling causes the formation of blood islands? |
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Definition
SHH signalling from Endoderm of Yolk Sac triggers BMP signalling from Splanchnic Mesoderm. BMP signals Mesenchyme to differentiate |
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Term
What special stem cell developes in blood islands? |
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Definition
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Term
Hemangioblasts differentiate into what cells? |
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Definition
Hemocytoblasts (inner) and Angioblasts (outer) |
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Term
What is the function of Hemocytoblasts? |
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Definition
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Term
What is the function of Angioblasts? |
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Definition
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Term
What signals vasculogenesis in blood islands? |
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Definition
VEGF (Vascular Endothelial Growth Factor) signalling from mesenchyme |
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Term
What signalling causes Angiogenesis (sprouting)? |
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Definition
Angiopoietin-1 from mesenchyme |
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Term
What causes of migration of mesenchymal cells to blood vessels during the completion of the vascular wall? |
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Definition
Platelet Derived Growth Factor PDGF |
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Term
What signalling causes the differentiation of mesenchymal cells into smooth muscle during the completion of the vascular wall? |
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Definition
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Term
Mutations in the Tie-2 receptor can lead to what pathology? |
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Definition
Tie-2 is an angiopoietin receptor. Malfunction of this receptor can lead to excessive vascular growth known as a hemangioma |
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Term
What is nevus vascularis? |
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Definition
hemangioma characterized by excessive capillary growth |
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Term
What is a cavernous hemangioma? |
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Definition
hemangioma in larger venous sinuses that can lead to CNS compression |
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Term
What is Sturge-Weber Syndrome? |
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Definition
Angioma of the meninges of the brain |
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Term
What is Port-wine stain hemangioma? |
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Definition
hemangioma anterior or lateral on the neck, sharp demarcation at midline |
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Term
What are the ciculatory arches that develop in angiogenesis? |
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Definition
Cardiac primordium, vitelline vessels, and umbilical vessels |
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Term
What is derived from the cardiac primordium? |
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Definition
Heart, ventral aortic root, internal carotid artery, anterior cardinal vein, aortic arches, pharyngeal pouch, common cardinal vein, dorsal aorta, and posterior cardinal vein |
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Term
What is derived from vitelline vessels? |
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Definition
Superior mesenteric artery and venous drainage |
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Term
What is derived from umbilical vessels? |
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Definition
No adult derivative of umbilical vessels should remain |
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Term
How does vasculature develop? |
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Definition
Begins in capillary beds and grow towards bigger vessels. This is why vasculature can have variation |
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Term
Hemocytoblasts give rise to which stem cells? |
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Definition
Myeloid and Lymphoid stem cells |
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Term
Myeloid stem cells give rise to what cells? |
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Definition
Granulocytes, Platelets, and Red Blood Cells |
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Term
Lymphoid stem cells give rise to what cells? |
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Definition
B/T lymphocytes and natural killer cells |
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Term
What is the primary source of RBC's after birth? |
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Definition
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Term
What is the primary form of endogenous RBC production in a fetus under three months old? |
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Definition
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Term
What is the primary source of RBC production in a fetus between 3-6 months old? |
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Definition
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Term
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Definition
Fetal erythrocytes: zeta/alpha and episilon chains |
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Term
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Definition
Fetal Eythrocytes: Zeta and gamma chains |
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Term
What are gamma hemoglobin chains? |
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Definition
fetal hemoglobin that are bind with alpha chains until enough adult beta chains are being produced |
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Term
What signalling molecule is important for the formation of lymphatics? |
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Definition
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Term
From where do lymphatics come from? |
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Definition
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Term
What happens when lymphatic trunks do not reach to critical lymphatic ducts? |
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Definition
Cystic Hygroma. Allows for a big collection of edema. Associated with Turners Syndrome |
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