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ATLAS Steven B. Oppenheimer Richard L. C. Chao a '. ~ ....-< Atlas of Embryonic Development Stevp.n K. Oppenheimer Richard L. C. Chao Califomia Stale 1.ll1ivpr~ily, Northridge Copyright C 1984 byAllyn and Bacon, Inc., 7Well5 Avenue, Newton, Mas5achusetts 02159. All rights reserved. No part of the material protected by this COfliright BOIice may be reproduce:! or util1~ed in any form orbyany means, electronic or mecltanical, inc1udi ngph-otocopying.. recording. orbyany information storage and retrieval system, without written permission from the copyright owner. library of Congress UtaJosiI1l in Publication Data Oppenheimer, 5te"l'e!1 8~ 1944- Moils of embryonic development 1. Embryology--Atlases.1. Chao, Richard L. C. U. Title. [DNLM: 1. Embryology-Atlases. Q5 617062a] QL956.065a 1984 597.6'0413 83-27152 ISBN 0-205-{)6099-5 Printed in the United State5 01 America. 10987654321 88 87 86 8S 84 Preface Spermatogenesis and Oogenesis 1 I The Frog 5 A Frog Gametes 11 B Frog Blastula and Gastrula 14 C Frog Neurula 19 D Frog Tailbud, 4 mm Stage 29 E Frog, 5-8 mm Stages 36 F Frog, 10-18 mm Stages 45 II The Chick 55 A Chick Gastrula 58 B Ch ick, 26-33 Hour Embryos 61 C Chick, 50 Hour Emblyo 75 D Chick, 3-4 Day Embryos 86 III The Mammal 105 A Cat and Rat Gonads 107 B Pig, 6 mm Embryo 11 0 C Pig, 10 mm Embryo 113 o Human Development 132 Appendix 135 Pla nes and Sections Term inology Used in this Atlas 136 Obtai ni ng Frog Embryos for Microscopy for this Atlas 137 Obtaining Chick Embryos for Microscopy for this Atlas 138 Preparation of Specimens for Scann ing Electron Microsco py (or this Atla s 139 Refere nces Used for Preparing Embryos for Scanning Electron Microscopy 140 Light Microscopy Eq uipment Used for this Atlas 141 Holtfreter's Solution 142 Amphi bian Ringer's Solution 143 Howard Ringer's Solution 144 Glossary 145 Preface Th is alla$ includes light micrographs and scanning electron micrographs of sped mens used in most developmental biology and embryology courses. We include the Kanning micrographs to shOlvthree-dimensiOllal qualities such as texture and depth that wou ld not be apparent from light micrographs alone. All fjgures are labeled for easy study, and transver>e ~1iom inciLIle diagrams that indicate the position of the section in the whole embryo. Developmental timetables and sketches incl uded should help ,Iudents under­ stand the sequence of e\en ~ occurring during embryonic development from a strlJctural standpoint. tn addition, drawings have been placed in appropriate sections of this atlas that wil l help students grasp the nature of the tissue movements and rearrangements that lead to the observed strLCtural changes that are characteristic of different devekpmental stages. Finally, a glossary of terms is included that will faci litate the definition of structures labeled in the micrograph ,. We thank Mary Beth Finch, Jim Sm ith, Joh n Gi lman, Vicky Prescott and Sandi Kirshner for excellent assistance in the development and production of this Ixx:.>k and the entire staff of Allyn and Bacon for concerted effort;; in the final stages of its prod; ction and distribution. Spermatogenesis and Oogenesis prophiSe of mei o,;. J leptotene I p.chyten. I ~ d,plot.n~ ~ :.105" miY be arrested in diplotene for many month, or yurs (for example, ~ meuph= __' an. phue 12 to SO yeirs in hum. n beiniS) secondiry ooc;yte Figure 1. Meiosis I in vertebrate oogenesis. From S. B. Oppenheimer, Introduc­ tion to Embryonic Development, 2nd Ed. (BostOll : Allyn and Bacon, 1984). -- ~-- I J. -_• I I ~-_1..._, _.""- _ 'ot ___ 1 II ""'-- . I I -. SPERMATOGENESIS AND OOGENESIS J spermatogonia'" Figure J. Summary of spermatogenesis. From S. B. Oppenheimer, IntJoduction to Embryonic Development, 2nd Ed . (Boston: Allyn and Bacon, 1984). 4 SPERMATOGEN ESIS AN O OOGENESIS oocyle 1\ m""' AA ,, o 0 SP ERM ATOG ENES IS OOGENES IS Figure 4. Comparison of spermatogenesis and oogenesis. From S. B. Oppen­ heimer, Introducrion to Embryonic Dcvelopmcnt, 2n d Ed . (Boston: Allyn an d Bacon, 1984). I Th Fro THE FROG 7 TABLE 1. Development of Rana pipiens at la"c Stage Age in Size in number hours millimeters Characteristic s 0 1. 75 unfertilized egg 2 1. 0 1.8 gray crescent 3 3.5 1. 8 2 cell s 4 4.5 1. 8 4 cells 5 5. 7 1. 8 8 cells 6 6.5 18 16 ce ll s 7 7.5 1.8 32 cells 8 16 1.8 early blastula 9 21 1.8 late blastula 10 26 1.8 early gastrula (dorsal li p) 11 34 1. 9 middle ga strula (crescent blastopore) 12 42 2.0 late gastrula (yo lk plug) 13 50 2.2 neural pl ate 14 62 2.3 neu ral fo lds 15 67 2.4 cil ia rotation begins 16 72 2.5 complete neural tube 17 84 3. 0 tai l bud 18 96 4.0 muscular movement 19 11 8 5.0 heart beats 20 140 6.0 gil) ci rcu lation and hatching 21 162 7.0 mouth open; cornea is transparent 22 192 8.0 tail fi n circulati on 23 216 9.0 opercular fo ld; teeth 24 240 10.0 operCU lu m closed on righ t 25 284 11. 0 operculum complete IBa sed on results of W. Shumway, Anal. Rec. 78: 139-148 (1940)) 8 THE FROG fert ilized ••cleav ,1e.ge " ta ilbud ~ ~ ~ I I 'i]~ ) d ~. gill bud, y" V " ~ , '" ,1 V 11 , I I , , ] \' " d V' hatching. gill circuld!inn } "~ll ,I ~~: ,! , , r' e" ', , ... ' : J ! \ r } \0;' , 1" moulh orx' ~ Tab le 1. Stages of frog deve lopment (continurdi. d, View from Jl1imal po le (frontal view); c, CJlldJI (b l asto~ r JIJ vi ew; d, dOrs.ll view; >, left la tera l view; v, ventral view. {From Del'e!opment of the Vert r br<l t!'> by Emil Witsc hi. Copyrigh t 1956 by W B. Sallnder, Co. UsC'd with permis sion Of the W . B. Saunders Co.l THE FROG 9 ___ tailfin circulation opercula r foId_ d --- right operculum cI <»ed operculum complete _ . .; ." -. :;f" 1 ___ metamorpho,i. ~, .-.. ,; Table 1. Stages of frog development (continued) . .a, View from an imal pole (frontal view); c, caudal (blastoporal) view; d, dorsal view; 5, left lateral view; II, ventra l view. (From Development of the Vertebrates by Emil Witschi. Copyright 1956 by W. B. Saunders Co. Used with permission of the W. B. Saunders Co.) 10 THE FROG d d metamorphosis Table 1. Stages of frog development (continued) . il, View from animal pole (frontal view); c, caudal (blastoporal) view; d, dorsal view; s, left lateral view; v, ventral view. (From Development of the Vertebrates by Emil Witschi. Copyright 1956 by W. B. Saunders Co. Used with permission of the W. 13. Saunders Co.) A. Frog Gametes nucleoli (black dots) theca externa nuclear membrane oocyte oocyte nucleus (ge rm inal vesicle) shrinkage artifact Figure 5. Frog ovary. (66,6 x) 11 12 THE FROG nuclei of nuclear follicle cells oocyte cytoplasm membrane nucleoli nucleus (germinal vesicle) Figure 6. Frog oocyte, enlarged. (621.6x) A. Frog Gametes 13 seminiferous tubules spermatocytes sperm lumen Sertoli cell Figure 7. Frog testis s~owing seminiferous tubule. (404.8x ) B. Frog Blastula and Gastrula anima l region blastocoel artifacts figure 8. Early frog blastu la. scanning electron micrograph. (137.2 x ) B. Frog Blastula and Gastrula 15 micromeres an ima) (dark spots are nuclei) pole fe rti lization membrane blastocoel shrinkage artifact macromeres vegetal pole figure 9. Frog blastula. (92.5 xl 16 THE FROG neur~ltube epidermis • notochord lip nQll-ootcx:hord~1 dOfS.Illip mesoderm be,in ning , , archenteron ,-"'m~."';; .. neur.1 plue epidermi, endoderm ~;<7 n,ural tuhe \'O;;;':!C->\\p'O.Pe<;tive ~rch en l . ron' notochord rr----.; r' ,.-: ' '--,-c' . Pro.~ti~ e' prospective . ' A _A • nOll'nQlcx:hord~1, i",~ , :,::::,"~"~_:::::":m:,:'~ mesoderm prospective , 1 notcx:hord - ::~::;,;~~. epidermis "I ,.J Figure to. Gastrulation in the amphibian. Keller and colleagues, working with Xenopus, a frog, found that prospective mesoderm may be located in deeper layers of the blastula instead of in surface regions. After W. Vogt., Raux Arch. 120, 385-706 (1929). From S. B. Oppenheimer, introduction to Embryonic De­ velopment 2nd Ed. (Boston; Allyn and Bacon, 1980). B. Frog Blastula and Ga<;trula 17 fertilization membrane blastocoel blastopore dorsal lip of blastopore Figure 11 . Early frog gostrulo. (92 S x ) 18 THE FROG archenteron roof archenteron dorsa! lip of blastopore yo lk plug ventral lip of blastopore fert il ization membrane Figure 12. Frog yolk plug. (97.5 x ) C. Frog Neurula non-notochordal mesoderm o (I.) tWO layered st.n . : oule, Ibl 1,1 ectoderm and inner mesendode,m neuf.ltu!>c notochord somite intermediate me.o<t.rm endoderm Id) Figure 13. Formation of the three-layered state in the amphibian. Coelom for­ mation occurs by mesodermal splitting. From S. 8. Oppenheimer, Introduction to Embryonic Development, 2nd Ed. (Boston: Allyn and Bacon, 1984). 20 THE FROG neural folds neural groove neural crest prospective epidermis foregut yolky endoderm fertilization membrane Figure 14. Frog embryo, neural fold stage, transverse section through foregut. (185 xl C. Frog Neurul a 21 neural groove neural fold fertilization membrane somite (epimere) notochord midgut hypomere prospective epidermis yolky endoderm Figure 15. Frog embryo, neural fold stage, transverse section through midgut. (185 x) 22 THE FROG fertilization membrane neural groove neural fold prospective epidermis hindgut Figure 16. Frog embryo, neural fold stage, transverse 5ection through hindgut.
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  • Semaphorin3a/Neuropilin-1 Signaling Acts As a Molecular Switch Regulating Neural Crest Migration During Cornea Development

    Semaphorin3a/Neuropilin-1 Signaling Acts As a Molecular Switch Regulating Neural Crest Migration During Cornea Development

    Developmental Biology 336 (2009) 257–265 Contents lists available at ScienceDirect Developmental Biology journal homepage: www.elsevier.com/developmentalbiology Semaphorin3A/neuropilin-1 signaling acts as a molecular switch regulating neural crest migration during cornea development Peter Y. Lwigale a,⁎, Marianne Bronner-Fraser b a Department of Biochemistry and Cell Biology, MS 140, Rice University, P.O. Box 1892, Houston, TX 77251, USA b Division of Biology, 139-74, California Institute of Technology, Pasadena, CA 91125, USA article info abstract Article history: Cranial neural crest cells migrate into the periocular region and later contribute to various ocular tissues Received for publication 2 April 2009 including the cornea, ciliary body and iris. After reaching the eye, they initially pause before migrating over Revised 11 September 2009 the lens to form the cornea. Interestingly, removal of the lens leads to premature invasion and abnormal Accepted 6 October 2009 differentiation of the cornea. In exploring the molecular mechanisms underlying this effect, we find that Available online 13 October 2009 semaphorin3A (Sema3A) is expressed in the lens placode and epithelium continuously throughout eye development. Interestingly, neuropilin-1 (Npn-1) is expressed by periocular neural crest but down- Keywords: Semaphorin3A regulated, in a manner independent of the lens, by the subpopulation that migrates into the eye and gives Neuropilin-1 rise to the cornea endothelium and stroma. In contrast, Npn-1 expressing neural crest cells remain in the Neural crest periocular region and contribute to the anterior uvea and ocular blood vessels. Introduction of a peptide that Cornea inhibits Sema3A/Npn-1 signaling results in premature entry of neural crest cells over the lens that Lens phenocopies lens ablation.