Book - The Early Embryology of the Chick: Difference between revisions

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# [[Book_-_The_Early_Embryology_of_the_Chick_11|Extra-embryonic Membranes]] The folding off of the body of the embryo; the establishment of the yolk-sac and the delimitation of the embryonic gut; the amnion and the serosa; the allantois.  
# [[Book_-_The_Early_Embryology_of_the_Chick_11|Extra-embryonic Membranes]] The folding off of the body of the embryo; the establishment of the yolk-sac and the delimitation of the embryonic gut; the amnion and the serosa; the allantois.  
# [[Book_-_The_Early_Embryology_of_the_Chick_12|The Structure of Chicks from Fifty to Fifty-five Hours of Incubation]]
# [[Book_-_The_Early_Embryology_of_the_Chick_12|The Structure of Chicks from Fifty to Fifty-five Hours of Incubation]]
## I. External Features.
## External Features.
##II. The Nervous System. Growth of the telencephalic region; the epiphysis; the infundibulum and Rathke's pocket; the optic vesicles; the lens; the posterior part of the brain and the cord region of the neural tube; the neural crests.  
##The Nervous System. Growth of the telencephalic region; the epiphysis; the infundibulum and Rathke's pocket; the optic vesicles; the lens; the posterior part of the brain and the cord region of the neural tube; the neural crests.  
##III. The Digestive Tract. The fore-gut; the stomodaeum; the pre-oral gut; the mid-gut; the hind-gut.  
##The Digestive Tract. The fore-gut; the stomodaeum; the pre-oral gut; the mid-gut; the hind-gut.  
##IV. The Visceral Clefts and Visceral Arches. V. The Circulatory System. The heart; the aortic arches; the fusion of the dorsal aortae; the cardinal and omphalomesenteric vessels. VI. The Differentiation of the Somites. VII. The Urinary System.  
##The Visceral Clefts and Visceral Arches. V. The Circulatory System. The heart; the aortic arches; the fusion of the dorsal aortae; the cardinal and omphalomesenteric vessels. VI. The Differentiation of the Somites. VII. The Urinary System.  
# [[Book_-_The_Early_Embryology_of_the_Chick_13|The Development of the Chick During the Third and Fourth Days of Incubation]]
# [[Book_-_The_Early_Embryology_of_the_Chick_13|The Development of the Chick During the Third and Fourth Days of Incubation]]
## I. External Features. Torsion; flexion; the visceral arches and clefts; the oral region; the appendage buds; the allantois.
##External Features. Torsion; flexion; the visceral arches and clefts; the oral region; the appendage buds; the allantois.
## II. The Nervous System. Summary of development prior to the third day; the formation of the telencephalic vesicles; the diencephalon; the mesencephalon; the metencephalon; the myelencephalon; the ganglia of the cranial nerves; the spinal cord; the spinal nerve roots.  
## The Nervous System. Summary of development prior to the third day; the formation of the telencephalic vesicles; the diencephalon; the mesencephalon; the metencephalon; the myelencephalon; the ganglia of the cranial nerves; the spinal cord; the spinal nerve roots.  
## III. The Sense Organs. The eye; the ear; the olfactory organs,  
## The Sense Organs. The eye; the ear; the olfactory organs,  
## IV. The Digestive and Respiratory Systems, Summary of development prior to the third day; the establishment of the oral opening; the pharyngeal derivatives; the trachea; the lung-buds; the oesophagus and stomach; the liver; the pancreas; the mid-gut region; the cloaca; the proctodaeum and the cloacal membrane.  
## The Digestive and Respiratory Systems, Summary of development prior to the third day; the establishment of the oral opening; the pharyngeal derivatives; the trachea; the lung-buds; the oesophagus and stomach; the liver; the pancreas; the mid-gut region; the cloaca; the proctodaeum and the cloacal membrane.  
## V. The Circulatory System. The functional significance of the embryonic circulation; the vitelline circulation; the allantoic circulation; the intra-embryonic circulation; the heart.  
## The Circulatory System. The functional significance of the embryonic circulation; the vitelline circulation; the allantoic circulation; the intra-embryonic circulation; the heart.  
## VI. The Urinary System. The general relationships of pronephros, mesonephros, and metanephros; the pronephric tubules of the chick; the mesonephric tubules.
## The Urinary System. The general relationships of pronephros, mesonephros, and metanephros; the pronephric tubules of the chick; the mesonephric tubules.
## VII. The Coelom and Mesenteries.
## The Coelom and Mesenteries.

Revision as of 14:53, 14 January 2011

Preface

The fact that most courses in vertebrate embryology deal to a greater or lesser extent with the chick seems to warrant the treatment of its development in a book designed primarily for the beginning student. To a student beginning the study of embryology the very abundance of information available in the literature of the subject is confusing and discouraging. He is unable to cull the essentials and fit them together in their proper relationships and is likely to become hopelessly lost in a maze of details. This book was written in an effort to set forth for him in brief and simple form the early embryology of the chick. It does not purport to treat the subject from the comparative view point, nor to be a reference work. If it helps the student to grasp the structure of the embryos, and the sequence and significance of the processes he encounters in his work on the chick, and thereby conserves the time of the instructor for interpretation of the broader principles of embryology it will have served the purpose for which it was written.

In preparing the text, details have been largely omitted and controverted points avoided for the sake of clarity in outlining fundamental processes. While I would gladly have avoided the matters of cleavage and germ layer formation in birds, a brief description of them seemed necessary. Without some interpretation of the initial phases of development, the student has no logical basis for his study of the already considerably developed embryos with which his laboratory work begins. The treatment which it is desirable to accord to gametogenesis and maturation as processes leading toward fertilization would vary so greatly in extent and view point in different courses that it seemed inadvisable to attempt any general discussion of these phenomena.

The account of development has not been carried beyond the first four days of incubation. In this period the body of the embryo is laid down and the organ systems are established. Courses in general embryology rarely carry work on the chick beyond this phase of development. More extensive courses in which a knowledge of mammalian embryology is the objective, ordinarily pass from the study of three or four day chicks to work on mammalian embryos.

While the text has been kept brief, illustrations have been freely used in the belief that they convey ideas more readily and more accurately than can be done in writing. Direct labeling has been used in the figures to facilitate reference to them. Most of the drawings were made directly from preparations in the laboratory of Histology and Embryology of Western Reserve University School of Medicine. However, figures from other authors, particularly Lillie and Duval, have been used extensively for comparisons and for schemes of presentation. Several figures have been reproduced directly or with only slight modifications. These are designated in the figure legends.

I wish to acknowledge the assistance I received in the preparation of material by Mrs. Mary V. Bayes, and in the drawing of the figures by Mrs. Bayes and Dr. Louis J. Karnosh. I am "also indebted to my father, Prof. Wm. Patten of Dartmouth College for criticism of the figures, and to Dr. F. C. Waite of the School of Medicine, Western Reserve University for his helpful interest and cooperation in all phases of the preparation of the book and especially for his reading of the manuscript.


Bradley M. Patten. Western Reserve University, School of Medicine. Cleveland, Ohio.


Contents

  1. Introduction
  2. The Gametes and Fertilization The ovarian ovum; maturation, ovulation, and fertilization; the formation of the accessory coverings of the ovum; the structure of the egg at the time of laying; incubation.
  3. The Process of Segmentation The effect of yolk on segmentation; the unsegmented blastodisc; the sequence and orientation of the cleavage divisions in birds.
  4. The Establishment of the Entoderm The morula stage; the formation of the blastula; the effect of yolk on gastrulation; gastrulation in birds.
  5. The Formation of the Primitive Streak and the Establishment of the Mesoderm The location and appearance of the primitive streak; the origin of the primitive streak by concrescence of the blastopore; the formation of the mesoderm.
  6. From the Primitive Streak Stage to the Appearance of the Somites The primitive streak as a center of growth; the growth of the entoderm and the establishment of the primitive gut; the growth and differentiation of the mesoderm; the formation of the notochord; the formation of the neural plate; the differentiation of the embryonal area.
  7. The Structure of Twenty-four Hour Chicks The formation of the head; the formation of the neural groove; the regional divisions of the mesoderm; the coelom; the pericardial region; the area vasculosa.
  8. The Changes Between Twenty-four and Thirty-three Hours of Incubation The closure of the neural tube; the differentiation of the brain region;^ the anterior neuropore; the sinus rhomboidalis; the fate of the primitiv^e streak; the formation of additional somites; the lengthening of the fore-gut; the appearance of the heart and the omphalomesenteric veins; organization in the area vasculosa.
  9. The Structure of Chicks Between Tihrty-three and Thirty-nine Hours of Incubation (The divisions of the brain and their neuromeric structure; the auditory pits; the formation of extra-embryonic blood vessels ;^the formation of the heart; the formation of intra-embryonic blood vessels. ,
  10. The Changes Between Forty and Fifty Hours of Incubation Flexion and torsion; the completion of the vitelline circulatory channels; the beginning of the circulation of blood.
  11. Extra-embryonic Membranes The folding off of the body of the embryo; the establishment of the yolk-sac and the delimitation of the embryonic gut; the amnion and the serosa; the allantois.
  12. The Structure of Chicks from Fifty to Fifty-five Hours of Incubation
    1. External Features.
    2. The Nervous System. Growth of the telencephalic region; the epiphysis; the infundibulum and Rathke's pocket; the optic vesicles; the lens; the posterior part of the brain and the cord region of the neural tube; the neural crests.
    3. The Digestive Tract. The fore-gut; the stomodaeum; the pre-oral gut; the mid-gut; the hind-gut.
    4. The Visceral Clefts and Visceral Arches. V. The Circulatory System. The heart; the aortic arches; the fusion of the dorsal aortae; the cardinal and omphalomesenteric vessels. VI. The Differentiation of the Somites. VII. The Urinary System.
  13. The Development of the Chick During the Third and Fourth Days of Incubation
    1. External Features. Torsion; flexion; the visceral arches and clefts; the oral region; the appendage buds; the allantois.
    2. The Nervous System. Summary of development prior to the third day; the formation of the telencephalic vesicles; the diencephalon; the mesencephalon; the metencephalon; the myelencephalon; the ganglia of the cranial nerves; the spinal cord; the spinal nerve roots.
    3. The Sense Organs. The eye; the ear; the olfactory organs,
    4. The Digestive and Respiratory Systems, Summary of development prior to the third day; the establishment of the oral opening; the pharyngeal derivatives; the trachea; the lung-buds; the oesophagus and stomach; the liver; the pancreas; the mid-gut region; the cloaca; the proctodaeum and the cloacal membrane.
    5. The Circulatory System. The functional significance of the embryonic circulation; the vitelline circulation; the allantoic circulation; the intra-embryonic circulation; the heart.
    6. The Urinary System. The general relationships of pronephros, mesonephros, and metanephros; the pronephric tubules of the chick; the mesonephric tubules.
    7. The Coelom and Mesenteries.