Search results
Results from the WOW.Com Content Network
Mesenchyme (/ ˈ m ɛ s ə n k aɪ m ˈ m iː z ən-/ [1]) is a type of loosely organized animal embryonic connective tissue of undifferentiated cells that give rise to most tissues, such as skin, blood or bone. [2] [3] The interactions between mesenchyme and epithelium help to form nearly every organ in the developing embryo. [4]
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. Limb bud is undifferentiated mesenchyme enclosed by an ectoderm covering. Eventually, the limb bud develops into bones, tendons, muscles and joints.
Intermediate mesoderm or intermediate mesenchyme is a narrow section of the mesoderm (one of the three primary germ layers) located between the paraxial mesoderm and the lateral plate of the developing embryo. [1] The intermediate mesoderm develops into vital parts of the urogenital system (kidneys, gonads and respective tracts).
The limb bud remains active throughout much of limb development as it stimulates the creation and positive feedback retention of two signaling regions: the AER and its subsequent creation of the zone of polarizing activity (ZPA) with the mesenchymal cells. [5]
The AEF potentially functions as an inhibitor to fin outgrowth since removing the AEF results in the formation of a new AER and subsequently a new AEF. In addition, repeated AF removal leads to excessive elongation of the fin mesenchyme, potentially because of prolonged exposure of AER signals to the fin mesenchyme. [16]
Epithelial and mesenchymal cells differ in phenotype as well as function, though both share inherent plasticity. [2] Epithelial cells are closely connected to each other by tight junctions, gap junctions and adherens junctions, have an apico-basal polarity, polarization of the actin cytoskeleton and are bound by a basal lamina at their basal ...
The mesoderm forms mesenchyme, mesothelium and coelomocytes. Mesothelium lines coeloms. Mesoderm forms the muscles in a process known as myogenesis, septa (cross-wise partitions) and mesenteries (length-wise partitions); and forms part of the gonads (the rest being the gametes). [1] [unreliable source?] Myogenesis is specifically a function of ...
Mesenchymal cells determine limb identity, but the AER maintains limb outgrowth through FGF signal secretion [1] These experiments reveal that the limb mesenchyme contains the necessary information concerning limb identity, but the AER is needed to stimulate the mesenchyme to live up to its destiny (of becoming an arm, leg, etc.)