. A laboratory manual and text-book of embryology. Embryology. 3. The nuclear membrane and nucleolus disappear, the nucleoplasm and cytoplasm becoming continuous. 4. During the above changes the chromatic network of the resting nucleus resolves itself into a skein or spireme, the thread of which soon breaks up into distinct, heavily-staining bodies, the chromosomes. A definite number of chromo- somes is always found in the cells of a given species. The chromosomes may be block- shaped, rod-shaped, or bent in the form of a U. 5. The chromosomes ar- range themselves in the equa- torial plane of
. A laboratory manual and text-book of embryology. Embryology. 3. The nuclear membrane and nucleolus disappear, the nucleoplasm and cytoplasm becoming continuous. 4. During the above changes the chromatic network of the resting nucleus resolves itself into a skein or spireme, the thread of which soon breaks up into distinct, heavily-staining bodies, the chromosomes. A definite number of chromo- somes is always found in the cells of a given species. The chromosomes may be block- shaped, rod-shaped, or bent in the form of a U. 5. The chromosomes ar- range themselves in the equa- torial plane of the central spindle. If U-shaped the base of each U is directed toward a common center. The ampluaster and the eliro- mosomes together constitute a mitotic figure and at the end of the prophase this is called a monaster. Metaphase.—The longi- tudinal splitting of the chro- mosomes into exactly similar halves constitutes the meta- phase (Fig. S, IV, V). The aim of mitosis is thus accom- plished, an accurate division of the chromatin between the nuclei of the daughter cells. Anaphase.—At this stage the two groups of daughter chromosomes separate and move up along the central spindle fibers, each toward one of the two asters. Hence this is called the Master stage (Fig. 8, VI). At this stage, the centrioles may each divide in preparation for the next division of the daughter cells. Telophase (Fig. 8, VII, VIII).—1. The daughter chromosomes resolve them-. VI ..--". 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 Prentiss, Charles William, 1874-1915. Philadelphia, London, W. B. Saunders
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectembryology, bookyear1
