. The cell; outlines of general anatomy and physiology. e nucleus, which it contains, takes theform of a horse-shoe, separating itself from the delicate connectingthread which united it to the mother-nucleus. The cell-buds arenow mature, and after detaching themselves from the motherorganism, move about for a time in the sea-water as zoospores. II. Partial or Meroblastic Segmentation. If we disregard the case of certain Protozoa (Nodiluca), partialsegmentation occurs only in egg-cells. It may conveniently be con-sidered after unequal division. It is found in all cases where theamount of yolk p
. The cell; outlines of general anatomy and physiology. e nucleus, which it contains, takes theform of a horse-shoe, separating itself from the delicate connectingthread which united it to the mother-nucleus. The cell-buds arenow mature, and after detaching themselves from the motherorganism, move about for a time in the sea-water as zoospores. II. Partial or Meroblastic Segmentation. If we disregard the case of certain Protozoa (Nodiluca), partialsegmentation occurs only in egg-cells. It may conveniently be con-sidered after unequal division. It is found in all cases where theamount of yolk present is extremely great, and where the proto-plasm is clearly separated from it, being collected together in a discat the animal pole (Fig. 108). The nucleus, which is situated in thecentre of this disc, must assume a horizontal position when it de-velops into a spindle. Hence the first division plane is in a ver-tical direction, and appears first at the animal pole in the centre ofthe disc (Figs. 120 A, 121 A), as in an egg, in which unequal cleav-.
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Keywords: ., bookcentury1800, bookdecade1890, bookidcelloutlines, bookyear1895
