. The elements of experimental embryology. Embryology, Experimental; Embryology. 358 GRADIENT-FIELDS IN POST-EMBRYONIC LIFE disc is grafted on to the right side of the body, the proper way up and the proper way out (" heteropleural, antero-posterior, dorso- dorsal"), only the antero-posterior axis has been interfered with and reversed. In such case, the disc develops into a limb with a left-hand asymmetry on the right side of the body, with elbow. Fig. 173 Diagram illustrating experiments on the symmetry of limbs. The circles represent the limb-buds as grafted on to the right side of
. The elements of experimental embryology. Embryology, Experimental; Embryology. 358 GRADIENT-FIELDS IN POST-EMBRYONIC LIFE disc is grafted on to the right side of the body, the proper way up and the proper way out (" heteropleural, antero-posterior, dorso- dorsal"), only the antero-posterior axis has been interfered with and reversed. In such case, the disc develops into a limb with a left-hand asymmetry on the right side of the body, with elbow. Fig. 173 Diagram illustrating experiments on the symmetry of limbs. The circles represent the limb-buds as grafted on to the right side of the body. The letters R and L in the centre of the circles indicate the side of origin of the bud (right or left). The letters A, P, D, V inside the circle indicate the antero-posterior and dorso-ventral axes of the grafted bud, these letters outside the circle refer to the same axes of the body of the organism. The limb which develops is shown with a thick outline. The position of a reduplicated limb (should one develop; see footnote, p. 224) is indicated by the fine outline; the dotted line refers to the form which the limb would have taken if the dorso-ventral axis of the bud had been fixed at the time of grafting. Only medio-medial combinations are shown. (After Harrison, from de Beer, Biol. Rev. 11, 1927.) pointing forwards and hand pointing backwards: it has preserved its prospective antero-posterior polarity, in spite of the reversal of this relative to the body as a whole. But if a left limb-disc is grafted on to the right side of the body, the proper way out but upside down ("heteropleural, antero-anterior, dorso-ventral"), the antero- posterior axis has been respected and only the dorso-ventral axis. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Huxley, Julian, 1887-1975; De Beer, Gavi
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Keywords: ., bookcentury1900, bookcollectionbiodiversi, booksubjectembryology
