Category:Carnegie Stage 7

From Embryology

This Embryology category shows pages and media related to Carnegie stage 7 of embryonic development. In human development this stage occurs during week 3 (post-fertilisation) or gestational age GA week 5 (LMP).


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Carnegie Collection - Stage 7 
Serial No. Grade Fixative Embedding Medium Thinness (µm) Stain Year Notes
7802 Exc. Alc. & Bouin C-P 6 (Stain - Haematoxylin Eosin) 1940 Heuser et al. (1945)
8206 Good p C-P 6 (Stain - Haematoxylin Eosin) 1943
8361 Good Bouin C-P 10 p 1946 Abnormal
8602 Exc. Alc. C-P 8 (Stain - Haematoxylin Eosin) 1948
8752 Exc. ? C-P 10 (Stain - Haematoxylin Eosin) 1950
8755 Exc. Formol C-P 10 (Stain - Haematoxylin Eosin) 1950
9217 Exc. p P 10 (Stain - Haematoxylin Eosin) 1954
Abbreviations
  • Grade - total grade of the specimen and includes both its original quality and the condition of the mounted sections.
  • Embedding medium - paraffin (P) or a combination of celloidin and paraffin (C-P).
  • Fixative - formalin (Formol), alcohol and formalin (Alc, formol), Bouin (Bouin solution)
  • ? - unknown or not determined.


Embryo Examples

Based on O'Rahilly, R. and Müller (1987).[1] and listed in order of length of notochordal process.

  • HEB-37. Summarized by Mazanec (1959)[2]. Chorionic cavity, 2.25 x 1.29 x 0.4 mm. Embryonic disc, 0.4 mm. Primitive streak, 0.104 mm, and node, 0.04 mm. Notochordal process, 0.032 mm. Stalk of umbilical vesicle (ibid., fig. 77). Median projection published (ibid., fig. 45).
  • H. R. 1. Described by Johnston (1940)[3], who believed that a notochordal process (0.04 mm) and a prechordal plate (0.075 mm) were present. Florian in an appendix to the article disagreed, and his interpretation is followed here (see stage 6).
  • Biggart. Described by Morton (1949)[4]. Curettage. Embryonic disc (narrow type), 0.27 x 0.16 mm. Primitive streak and node, 0.059 mm. A notochordal process is not referred to in the text but is mapped on a dorsal projection of the embryo (ibid., fig. 2) and is approximately 0.04 mm in length. The specimen is said to resemble the Yale embryo.
  • Guá (Guálberto). Described by Lordy (1931)[5]. Hysterectomy. Chorionic cavity, 8 x 7.5 mm. Embryonic disc, 0.776 x 0.0465 mm. Primitive streak, 0.09 mm. Notochordal process, 0.045 mm. Possible notochordal canal. Said to resemble Hugo embryo. Probably belongs either to stage 7 or to stage 8.
  • 7802 An important specimen described and illustrated by Heuser, Rock, and Hertig (1945)[6]. Hysterectomy. Chorion, 3.75 x 2.35 x 2.2 mm. Chorionic cavity, 2.3 x 1.4 x 1.1 mm. Embryonic disc (broad type), 0.42 x 0.35 x 0.05 mm. Primitive streak, 0.11 mm, and node, 0.03 mm. Notochordal process, 0.048 mm. Presumed age, 16 days. Median projection published (ibid., plate 6; Mazanec, 1959, fig. 46) and dorsal projection has been prepared by the present writers.
  • P.M. Described by Meyer (1924)[7]. Curettage. Measurements have been criticized by Stieve (1926) but defended by Mazanec (1959)[2]. Chorion, 3.9 x 3.77 x 2.5 mm. Chorionic cavity, 2.7 x 2.6 x 2.1 mm. Embryonic disc (circular), 0.41 x 0.41 mm. Primitive streak, 0.12 mm, and node, 0.02 mm. Notochordal process, 0.06 mm, acknowledged by Mazanec (1959)[2]. although denied by Fahrenholz (1927)[8]. No notochordal canal. Median projection published (Mazanec, 1959, fig. 47).
  • Hugo. Described by Stieve (1926)[9], who reproduced a photomicrograph of every second section. Hysterectomy. Surrounded by 942 chorionic villi ranging in length from 0.3 to 1 mm. Chorion, 6.4 x 5.9 x 5.6 mm. Chorionic cavity, 4.7 x 4.4 x 3.8 mm. Embryonic disc (broad type), 0.635 (Florian, 1931) x 0.63 mm. Primitive streak, 0.245 mm, and node, 0.05 mm. Notochordal process, 0.07 (0.11?) mm. (Florian, 1934c). No notochordal canal. Prechordal plate probably not yet developed (Hill and Florian, 1931a). Dorsal and median projections published (Florian, 1934c[10], fig. 1; Hill and Florian, 1931b[11], figs. 44 and 11; Mazanec, 1959[2], fig. 49).
  • Robertson, O’Neill, and Chappell (1948)[12] described a hysterectomy specimen that possessed a chorion of 3.816 x 3.639 x 2.687 mm. Chorionic cavity, 2.718 x 2.239 x 1.679 mm. Embryonic disc (broad type), 0.462 x 0.485 mm. Primitive streak, 0.138 mm, and node (situated halfway), 0.03 mm. Notochordal process, 0.072 mm. Suggestion of notochordal canal in one or two sections. Assigned to horizon VIII by authors but probably belongs to stage 7. Median projection published (ibid., fig. 12).
  • D’Arrigo (1961)[13] described an embryonic disc of 0.47 mm, which showed a notochordal process of 0.075 mm. Canalization of the process is “doubtful,” but the presence of a prechordal plate is “probable.” The specimen “could be recorded in Streeter’s horizon VII.”
  • Goodwin. Described by Kindred (1933).[14] Tubal. Chorion, 5.8 x 2.72 x 2.25 mm. Chorionic cavity, 2.44 x 2.25 x 0.75 mm. Embryonic disc, 0.588 mm in width. Primitive streak, 0.215 mm, and node, 0.078 mm. Notochordal process, 0.078 mm. No notochordal canal and no prechordal plate.
  • Pha I. Described by Mazanec (1949)[2]. Chorionic cavity, 7.872 x 5.475 x 2.032 mm. Embryonic disc, 0.66 x 0.52 mm. Primitive streak, 0.145 mm, and node, 0.06 mm. Notochordal process, 0.09 mm. No prechordal plate. Median projection published (ibid., fig. 51).
  • H. Schm. 10 (H. Schmid). Described briefly by Grosser (1931)[15]. Embryonic disc (almost circular), 0.51 x 0.58 mm. Primitive streak, 0.14 mm, and node, 0.1 mm. Notochordal process, 0.1 mm. Probably belongs to stage 7, although a cavity in one section was thought to represent “Lieberkühn’s canal.”
  • Bi 24 (Bittmann). Described by Hill and Florian (1931b)[11]. Chorionic cavity, 3.05 x 3.036 x 3.029 mm. Embryonic disc (narrow type), 0.62 x 0.39 mm. Primitive streak, 0.28 mm, and node (Mazanec, 1959, fig. 105), 0.05 mm. Notochordal process, 0.105 mm, consists of median chord and lateral mesoblastic wings. Prechordal plate, 0.03 mm. Possible primordial germ cells in endoderm of region of cloacal membrane and in endoderm of umbilical vesicle caudally (Florian, 1931). Politzer (1933)[16] counted 41 germ cells in the region of the allanto-enteric diverticulum in this embryo, and 19 such cells in another presomite specimen (Bi 25). Dorsal and median projections published (Hill and Florian, 1931b, figs. 4 and 12; Florian, 1945, plate 5, fig. 43; Mazanec, 1959, fig. 50).
  • Manchester No. 1285 (fig. 7-1). Described by Florian and Hill (1935)[17],. Hysterectomy. Chorionic cavity, 4.28 x 3.28 mm. Embryonic disc (narrow type), 0.87 x 0.625 mm. Primitive streak, 0.39 mm, and node, 0.05 mm. Notochordal process, 0.125 mm. Prechordal plate, 0.03 mm. Connecting stalk attached to chorion at decidua capsularis (suggesting polar variety of velamentous insertion of umbilical cord). Dorsal and median projections published (Hill and Florian, 1931b, figs. 5 and 13; Florian and Hill, 1935, figs. 1-3; Mazanec, 1959[2], fig. 52). Specimen is housed in Department of Anatomy, University of Manchester.
  • Pha II. Summarized by Mazanec (1959)[2]. Chorionic cavity, 4.985 x 3.882 x 3.52 mm. Embryonic disc, 0.895 x 0.62 mm. Primitive streak, 0.37 mm, and node, 0.06 mm. Notochordal process, 0.13 mm. No prechordal plate. Median projection published (ibid., fig. 53).
  • Thompson and Brash (1923)[18] described a specimen that showed a notochordal process of 0.3 mm.


Following embryo examples do not have measurements of the notochordal process, they are listed by the year of publication.

  • Debeyre (1912)[19] described in detail a specimen that possessed a chorionic cavity of 5.6 x 2.1 mm. Embryonic disc, 0.9 x 0.6 x 0.95 mm. Primitive streak stated to be 0.54 mm in length. Chorionic villi (0.4-1.6 mm) showed some branching. Unsuitable plane of section makes it impossible to assess the specimen precisely.
  • Carnegie No. 1399, Mateer. Described by Streeter (1920). Hysterectomy. Angiogenesis in villi described by Hertig (1935). Chorion, 9 x 8 x 3.5 mm. Chorionic cavity, 6.1 x 5.6 x 2.5 mm. Embryonic disc, 1 x 0.75 mm. Primitive streak and groove present. Although the notochordal process was originally thought probably to be absent, Hill and Florian (1931b) have no doubt that it is present. More advanced than Hugo (Florian and Völker, 1929). A very small twin embryo was originally described but that “interpretation has become open to doubt” (Corner, 1955). Drawing of every section reproduced by Turner (1920). A median drawing (Davis, 1927, fig. 5A) and a projection have been published (Mazanec, 1959, fig. 56).
  • Ho (Hodiesne). Described by Fahrenholz (1927). Abortion. Chorionic cavity, 6.5 x 6 x 3 mm. Embryonic disc (deformed), 0.6 mm (0.725 mm by flexible scale). Primitive streak, 0.22 mm (0.345 mm by flexible scale). Notochordal process just beginning (“undoubtedly present,” Hill and Florian, 1931b). Possible prechordal plate claimed (disputed by Waldeyer, 1929a, but supported by Hill and Florian, 1963). “Lieberkühn’s canal” (0.065 mm) is an artificial folding of the embryonic disc (Hill and Florian, 1931b). Dorsal and median projections published (Fahrenholz, 1927, figs. 32, 6 and 7; Mazanec, 1959, fig. 54).
  • Debeyre (1933)[20] described a specimen (0.9 mm) that possessed a primitive streak and probably belonged to stage 6 or stage 7. Large cells near the opening of the allantois were identified as primordial germ cells.
  • Falkiner. Described by Martin and Falkiner (1938)[21]. Curettage. Embryo damaged and not in good condition. Measurements seem too small (see Mazanec, 1959). Chorionic cavity, 1.5 x 1.4 mm. Embryonic disc, 0.15 x 0.29 mm. Primitive streak, 0.07 mm. Notochordal process contains “no definite lumen.” Cells rostral to notochordal process are “probably” the prechordal plate. Development “agrees most closely” with that of Bi I. Median projection published (Martin and Falkiner, 1938, fig. 8; Mazanec, 1959, fig. 39).
  • Gar (Green-Armytage). Described by West (1952)[22]. Hysterectomy. Chorionic cavity, 3 x 2.6 x 2 mm. Embryonic disc (broad type), 0.56 x 0.69 mm. Primitive streak, node, and groove present. Short notochordal process. No notochordal plate. Said to resemble Hugo embryo. Trophoblast described by Hamilton and Boyd (1960).
  • Mal (Maliphant). Described by West (1952[22]). Hysterectomy. Chorionic cavity, 3 x 1.8 mm. Embryonic disc (broad type), 0.45 x 0.6 mm. Primitive streak, node, and groove present. Notochordal process present (Mazanec, 1959); small cavity in node (West, 1952)[22] or in notochordal process (Mazanec, 1959) “hardly sufficient to warrant the name chorda canal.” No prechordal plate. Belongs either to stage 7 or to stage 8 (said to resemble Jones-Brewer I, which is in stage 8).
  • Carnegie No. 8602. Photomicrograph reproduced by Hertig, Rock, and Adams (1956, plate 10, fig. 53)[23]. Chorion, 2.73 x 2.43 mm. Chorionic cavity, 1.83 x 1.33 mm. Embryonic disc, 0.3 x 0.06 mm. Presumed age, 16-17 days.
  • Missen. Trophoblast described by Hamilton and Boyd (1960)[24]. Curettage. Chorion, 1.66 x 1.43 mm. Embryonic disc, 0.28 x 0.214 mm. Primitive streak and node. Notochordal process. Said to resemble No. 7801 and Edwards Jones-Brewer (stage 6). Presumed age, about 14 days.

References

  1. O'Rahilly, R. and Müller, F. Developmental Stages in Human Embryos. Carnegie Institution of Washington Publication 637 (1987).
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Mazanec K. Blastogenese des Menschen. (1959) Fischer, Jena.
  3. Johnston TB. An early human embryo, with 0.55 mm. long embryonic shield. (1940) J. Anat., 75:1-49.
  4. Morton WRM. Two early human embryos. (1949) J. Anat., 83: 308-314.
  5. Lordy, C. 1931. A human ovum in its early phases of development. Ann. Fac. Med. Sao Paulo, 6, 29-35.
  6. Heuser, C. H., Rock, J., and Hertig, A. T. 1945. Two human embryos showing early stages of the definitive yolk sac. Carnegie Instn. Wash. Publ. 557, Contrib. Embryol., 31, 85-99.
  7. Meyer, P. 1924. Ein junges menschliches Ei mit 0,4 mm Iangem Embryonalschild. Arch. Gyndk, 122, 38-87.
  8. Fahrenholz, C. 1927. Ein junges menschliches Abortivei. Z mikr.-anat. Forsch., 8, 250-324.
  9. Stieve, H. 1926a. Ein 13V2-Tage altes, in der Gebarmutter erhaltenes und durch Eingriff gewonnenes menschliches Ei. Z mikr.-anat. Forsch., 7, 295-402.
  10. Florian, J. 1934c. Uber einige bisher unkorrigiert gebliebene fehlerhafte Angaben der junge menschliche Embryonen beschreibenden Arbeiten. Anat. Anz., 78, 445-450.
  11. 11.0 11.1 Hill, J. P., and Florian, J. 1931b. A young human embryo (embryo Dobbin) with head-process and prochordal plate. Phil. Tram. Roy. Soc. London B, 219, 443-486.
  12. Robertson, G. G., O'Neill, S. L, and Chappell, R. H. 1948. On a normal human embryo of 17 days development. Anat. Rec, 100, 9-28. PMID 18917638
  13. D'Arrigo, S. 1961. Illustrazione di un embrione umano al principio della terza settimana di sviluppo. Riv. Patol. Clin. Sper., 2, 1-15.
  14. Kindred JE. A human embryo of the pre-somite period from the uterine tube. (1933) Amer. J Anat. 53: 221-241.
  15. Grosser, O. 1931. Weiteres uber den Primitivstreifen des Menschen. Verb. Anat. Ges., Erg. Heft Anat. Anz., 72, 42-44.
  16. Politzer, G. 1933. Die Keimbahn des Menschen. Z. Anat. Entw., 100, 331-361.
  17. Florian, J., and Hill, J. P. 1935. An early human embryo (No. 1285, Manchester Collection), with capsular attachment of the connecting stalk. J. Anat,, 69, 399-411.
  18. Thompson P. and Brash JC. A human embryo with head-process and commencing arch enteric canal. (1923) J Anat. 58: 1-20. PMID 17103992
  19. Debeyre, A. 1912. Description d'un embryon humain de 0-mm.9. J. Anat. Physiol, Paris, 48, 448-515.
  20. Debeyre, A. 1933. Sur la presence de gonocytes chez un embryon humain au stade de la ligne primitive. C. R. Ass. Anat., 28, 240-250.
  21. Martin, C. P., and Falkiner, N. Mel. 1938. The Falkiner ovum. Amer.f. Anat, 63, 251-271.
  22. 22.0 22.1 22.2 West, C. M. 1952. Two presomite human embryos. J. Of eat Gynaecol. Brit. Emp., 59, 336-351.
  23. Hertig, A. T., Rock, J., and Adams, E. C. 1956. A description of 34 human ova within the first 17 days of development. Amer. J. Anat., 98, 435-493.
  24. Hamilton, W. J., and Boyd, J. D. 1950. Phases of human development. Ch. 8 in K. Bowes (ed), Modem Trends in Obstetrics and Gynaecology Butterworth, London, pp. 114-137.

Pages in category 'Carnegie Stage 7'

The following 55 pages are in this category, out of 55 total.

Media in category 'Carnegie Stage 7'

The following 84 files are in this category, out of 84 total.