48 hour chick embryo serial cross section

The primitive groove is being bound by primitive folds. In the middle of area pellucida, in the posterior half, runs a primitive streak having a primitive groove through its centre. In the anterior part is present the pro-amnion, which is a small and comparatively more translucent region of area pellucida and is characterised by the absence of mesoderm. At this stage the dark peripheral area opaca and central translucent area pellucida are distinctly visible. Caudal end of the streak is that which lies close to the area opaca. Elongated primitive streak represents long axis of future embryonic body.ĪDVERTISEMENTS: 6. Part of area pellucida adjacent to the primitive streak shows increased thickness and forms embryonic elliptical shape. Rc slipper clutch.Īt the cephalic end of the primitive streak, closely-packed cells form thickened area, called as Hensen’s node. Is composed of central furrow, called as primitive groove lined by thickened primitive ridges. Somewhat before the 48 hour mark, the embryo has begun to go through a torsional. 48 Hour Chicken Embryo, Whole Mount Between the 33 and 48 hour stages, there has been a marked increase in the complexity of the head. SUMIDA BIOLOGY 340 Comparative Embryology Laboratory Exercise 3. Labeled 2 will take you to a sub-menu page containing links to full-size images of serial sections between 2 and 28. 16 hours after incubation the primitive streak becomes so distinct that embryos are characterized as being in primitive streak stage.Ĥ8-hour Chick Embryo Small Image Menu. After 7 to 8 hours, the thickening becomes more elongated and represented start of primitive streak.

48 hour chick embryo serial cross section