development integumentary system (skin and appendages)
DESCRIPTION
Development Integumentary System (Skin and appendages). This is a sample chapter of the embryology book 'FETUS' by Dr Md Abedur Rahman.TRANSCRIPT
FETUSEssential elements of embryology
16th Edition
ABEDUR RAHMAN
MBBS (DMC), M Phil (DU)
Editorial Assistant Dr. Farzana Iqbal
Published byAfrazul Haque
Bhelejan Thakurgaon
On behalf of Fetus Publications
First published………. September, 1991. Second Edition………. September, 1993.
Third Edition………. February, 1995. Fourth Edition………. September, 995.
Fifth Edition……….January, 1997 Sixth Edition………. May, 1998
Seventh Edition……….March, 2000Eighth Edition……….August, 2000
Ninth Edition………. May, 2002 Tenth Edition………. October, 2003 Eleventh Edition………. April, 2004
Twelfth Edition………. December, 2004Thirteenth Edition………. February, 2006Fourteenth Edition……….October, 2006Fifteenth edition ……….January, 2008
Sixteenth edition ……….November, 2008
© MD. ABEDUR RAHMANAII rights reserved. No part of this book may be reproduced or transmitted in any form or
by any means without the written permission of the author.
Cover Design: Abedur Rahman
Price: Taka Three hundred and Twenty (320/-) only.
For all kinds of correspondence:DR MD ABEDUR RAHMAN Phone: +88 01819-050041
e-mail: [email protected]
FETUS
Dedicated to
My father
for the uncompromising
principle that guided his life.
ACKNOWLEDGEMENTS Integumentary System 332
Prof. Dr. Md. Nazrul Islam MBBS, M. Phil (DU), MS (Glasgow). MHPED (Australia) Principal, Dinajpur Medical College Ex Vice president, BMA
FETUS
I remember Dr. A. Hye Fakir
EX-Head of the department of anatomy, BSMMU. Dr. Habibur Rahman.
EX Head of the department of anatomy, SBMC Dr. Shahid-UlIah EX-Head of the department of anatomy, RPMC Dr. Kazi Rafiqul Haque
Head of the department of anatomy, USTC. Chittogong Late Dr. S.S. Banik. Ex-Associate Professor of anatomy, SSMC. Dr. Motahar Hossain. Ex-Head of the department of anatomy, DMC. Dr. Manjar-e-Shamim. Professor & head of the department of anatomy, BSMMU. Dr. Shamim Ara Head of the department of anatomy, DMC Dr. Shafiq Haider
Asst prof. of anatomy, CMC. for their good wishes to this publication Dr. Nazrul Islam
Principal, Dinajpur Medical College Dr. Rubaiual Morshed
Ex Asst. Professor, Pediatric Surgery, DMCH for their kind efforts in revising this book.
I am also grateful to Alauddin (SOMC) and other students who made constructive criticism to make the book more helpful for the students.
I want to acknowledge my students Juthy (K-63, DMC) and Sristi (K-63, DMC) for their whole hearted co-operation in editing this 16th edition of the book; Ilias (K-62, DMC), Juwel (K-63, DMC), Pritom (K-63, DMC), Fauzia (NUB) for their constructive criticism for making necessary correction of in this edition. I am also grateful to the doctors and students of different institutions and medical colleges who made constructive criticism to make the book more helpful for the embryology student.
Forewords
Excellent one
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Dr. Kazi Rafiqul Huq Head, dept. of Anatomy USTC, Chittogong.
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I have gone through the book and found that the author has been succeeded in presenting the essential elements of embryology in an excellent manner. The elements served here are authentic. I hope that this humble presentation will serve its purposes well. My best wishes go to the author.
Really charmed to find the simplicityI have gone through the book Fetus by Dr. Abedur Rahman with interest & have been really charmed to find the simplicity of its presentation & diagrams which depict the wide subject of embryology into the small space of this handy volume. Student can peep into the memory of the whole aspect of embryology through this book instantaneously and comfortably even at rest or in leisure like the cow which enjoys the taste of food by cutting its jaw while at rest.
I wish the promising young author & his book a glorious success in the days to come.
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AUTHOR’S SAYINGS
“The history of man for nine months preceding his birth would, probably, be far more interesting, and contain events
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of greater moment than all three score and ten years that follow it.”
--- Samuel Taylor Coleridge
It is now well proved that ‘Fetus’ is the most read embryology book in our country. The last 15 editions of the book have proven that it is unique in its field. In this edition, I have tried my best to make it more useful for the students making necessary changes elsewhere.
New to this edition- Development of different organs at a glance Answers of all first professional SAQ Some new information Some figures and information are modified.
All praises for the Almighty. Thanks to all the anatomy teachers and students – past, present, and future.
November 2008 Dr Md Abedur Rahman
ContentsIntegumentary System 336
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Part-1: Introduction
1. Introduction to embryology 1
2. Reproduction and Development 33. Some basic concepts in embryology 84. Some historical elements on embryology 12
Part-2: General Embryology
5. Gametogenesis: Conversion of germ cells into male & female gamete
21
6. Female reproductive cycles and ovulation 347. Pre-embryonic period – I: Fertilization, cleavage and
implantation68
8. Pre-embryonic period-II: Formation of germ layers (Gastrulation) 909. Embryonic period: Derivatives of germ layers 11510. Fetal period Some facts concerning the fetus 12311. Fetal membranes and placenta 12712. Congenital malformations 15513. Developmental genetics 159
Part-3: Systemic Embryology
14. Cardiovascular system 16515. Digestive system 19016. Respiratory system 23117. Diaphragm and septum transversum- 23718. Urogenital system 24119. Head neck and ear 27920. Nervous system 30421. Skeletal system 32522. muscular system 32923. Integumentary system 332Glossary 339
Fetus 2 contentsSAQ in EmbryologyDevelopment of Different organ at a Glance
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Look for the other books by the same author1. D”P evW †cÖmvi: cÖwZKvi I cÖwZ‡iva2. Medical Genetics3. Research methodology4. How to Write a thesis5. Essentials of Biostatistics
Sample chapter
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23
Integumentary System
Questions for written examination (1) Give the developments of skin(2.) Give the development of mammary gland IntroductionSkin & all its appendages (nail, hair, sebaceous, sweat & mammary gland) develop from surface ectoderm except dermis & melanocytes.
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Development of Skin Skin develops as follows—1. Epidermis with nails and hairs - from surface ectoderm. This is at first
single layered. By proliferation it gives rise to typical stratified sq. epithelium
2. Melanocytes-From neural crest
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3. Dermis — from underlying mesenchyme which comes from dermatome of the somites.
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Fig.: Derivation of components of the skin.
Viva Q.; How do you explain the supply of nail beds by palmer and
plantar nerves?
Ans. developmentally nails are thickening of epidermis and are found initially
on the palmar and plantar aspects of the palm & sole. It is their gradual
migration to the dorsal aspect which explains such nerve supply.
Development of mammary gland (breast)
An ectodermal ridge extending from axilla to the groin on each side of the body is called milk line. From a small part of this milk line breast develops through following sequence of events.
1. Thickened masses of epidermal cells project into dermis
2. Branching occurs in it and branches are canalized. Proximal ends of the branches form lactiferous duct and distal end proliferates to form secretory elements.
Milk line
Figure: A and B sections through the (developing mammary) gland at the third and eight months, respectively. C diagram showing the positions of
accessory nipples (broken line indicates position of mammary line).
Developmental Anomalies of Breast
Common anomalies of breast are (a) Amastia (absence of breast). (b) PoIymastia (Multiple breast), (c) Athelia (absence of one or both nipples). (d) Polythelia (Supernumerary nipples) (e) Gynaecomastia (occurrence of female breasts in the male)