(BQ) Part 1 book Inderbir singh human histology has contents: Light microscopy and tissue preparation, cell structure, epithelia, glands, general connective tissue, cartilage, bone, muscular tissue,.... and other contents.
Trang 2Textbook of Human HisTology
Inderbir Singh’s
Trang 3Late Professor Inderbir Singh
(1930–2014)
Tribute to a Legend
Professor Inderbir Singh, a legendary anatomist, is renowned for being a pillar in
the education of generations of medical graduates across the globe He was one of
the greatest teachers of his times He was a passionate writer who poured his soul
into his work His eagle’s eye for details and meticulous way of writing made his
books immensely popular amongst students He managed to become enmeshed in
millions of hearts in his lifetime He was conferred the title of Professor Emeritus
by Maharishi Dayanand University, Rohtak
On 12th May 2014, he has been awarded posthomously with Emeritus
Teacher Award by National Board of Examination for making invaluable
contribution in teaching of Anatomy This award is given to honour legends
who have made tremendous contribution in the field of medical education and
their work had vast impact on the education of medical graduates He was a
visionary for his times and the legacies he left behind are his various textbooks on
gross anatomy, histology, neuroanatomy, and embryology Although his mortal
frame is not present amongst us, his genius will live on forever
Trang 4Textbook of Human HisTology
Inderbir Singh’s
with Colour atlas and Practical guide
Revised and Edited by
Director Professor and Head, Department of AnatomyMaulana Azad Medical College, New Delhi
Professor, Department of AnatomyMaulana Azad Medical College, New Delhi
Seventh Edition
New Delhi | London | Philadelphia | Panama
The Health Sciences Publishers
Trang 5Jaypee Brothers Medical Publishers (P) Ltd
Headquarters
Jaypee Brothers Medical Publishers (P) Ltd
4838/24, Ansari Road, Daryaganj
New Delhi 110 002, India
Phone: +91-11-43574357
Fax: +91-11-43574314
Email: jaypee@jaypeebrothers.com
Overseas Offi ces
J.P Medical Ltd Jaypee-Highlights Medical Publishers Inc
83 Victoria Street, London City of Knowledge, Bld 237, Clayton
SW1H 0HW (UK) Panama City, Panama
Phone: +44 20 3170 8910 Phone: +1 507-301-0496
Fax: +44 (0)20 3008 6180 Fax: +1 507-301-0499
Email: info@jpmedpub.com Email: cservice@jphmedical.com
Jaypee Medical Inc Jaypee Brothers Medical Publishers (P) Ltd
The Bourse 17/1-B Babar Road, Block-B, Shaymali
111 South Independence Mall East Mohammadpur, Dhaka-1207
Suite 835, Philadelphia, PA 19106, USA Bangladesh
Phone: +1 267-519-9789 Mobile: +08801912003485
Email: jpmed.us@gmail.com Email: jaypeedhaka@gmail.com
Jaypee Brothers Medical Publishers (P) Ltd
Bhotahity, Kathmandu, Nepal
Phone: +977-9741283608
Email: kathmandu@jaypeebrothers.com
Website: www.jaypeebrothers.com
Website: www.jaypeedigital.com
© 2014, Jaypee Brothers Medical Publishers
The views and opinions expressed in this book are solely those of the original contributor(s)/author(s) and do not
neces-sarily represent those of editor(s) of the book.
All rights reserved No part of this publication may be reproduced, stored or transmitted in any form or by any means,
electronic, mechanical, photocopying, recording or otherwise, without the prior permission in writing of the publishers.
All brand names and product names used in this book are trade names, service marks, trademarks or registered
trade-marks of their respective owners The publisher is not associated with any product or vendor mentioned in this book.
Medical knowledge and practice change constantly This book is designed to provide accurate, authoritative information
about the subject matter in question However, readers are advised to check the most current information available on
procedures included and check information from the manufacturer of each product to be administered, to verify the
recom-mended dose, formula, method and duration of administration, adverse effects and contraindications It is the responsibility
of the practitioner to take all appropriate safety precautions Neither the publisher nor the author(s)/editor(s) assume any
liability for any injury and/or damage to persons or property arising from or related to use of material in this book.
This book is sold on the understanding that the publisher is not engaged in providing professional medical services If
such advice or services are required, the services of a competent medical professional should be sought.
Every effort has been made where necessary to contact holders of copyright to obtain permission to reproduce copyright
material If any have been inadvertently overlooked, the publisher will be pleased to make the necessary arrangements
at the fi rst opportunity.
Inquiries for bulk sales may be solicited at: jaypee@jaypeebrothers.com
Inderbir Singh’s Textbook of Human Histology
First Edition : 1987 Fifth Edition : 2006
Fourth Edition : 2002 Sixth Edition : 2011
Reprint : 2005 Seventh Edition : 2014
ISBN 978-93-5152-322-2
Printed at
Trang 6Textbook of Human Histology by Professor Inderbir Singh has remained an authoritative
and standard textbook for the past many decades and it is our proud privilege to revise this
book and bring out the 7th edition The strength and popularity of this textbook has been its
simple language and comprehensiveness that has essentially remained unchanged since its
inception Professor Singh’s eye for details and his meticulous writing style has always been
popular amongst the generations of medical students Although all the chapters have been
revisited and thoroughly revised, we have taken special care to retain the basic essence of the
book
To make this standard textbook fulfill the needs of today's generation of students, some
new features have been introduced in this edition A new chapter on Light Microscopy and
Tissue Preparation has been added to acquaint the students with the basics of histology Every
student of histology is expected to identify the slides and differentiate amongst them in a
perfect manner To make the students familiar with the various slides, Histological Plates have
been added in each chapter that include a photomicrograph, line drawing, and salient features
that are visible while examining under the microscope
Each chapter has been rearranged to provide sequential learning to the students All
the diagrams have been redrawn and many new illustrations have been added for easy
comprehension of the basic concepts Clinical and Pathological Correlations have been added
at relevant places for creating an interest of the students in the understanding of pathologies
associated with various tissues
For providing an overview of histology to the student and for quick recall, an atlas has been
provided at the beginning of the book The atlas includes more than 80 slides of histological
importance along with their important features
As envisioned by Professor Inderbir Singh, this textbook is of utmost utility not only for
the undergraduate students but also for the students pursuing postgraduation in Anatomy
Keeping this in mind, advanced information on various topics has been included as Added
Information to cater to the needs of postgraduate students
The revision of this book was a team effort We are thankful to our colleagues for their
constant encouragement throughout our venture We extend our heartfelt thanks to our staff in
the Histology laboratory for preparing the slides for photography We are thankful to Dr Sawti
Tiwari for her important contribution in drawing some of the figures
We are grateful to Professor Ivan Damjanov, an esteemed teacher and expert in the field
of pathology well known across the globe, for allowing us to use some of the slides from
his collection We gratefully acknowledge Professor Harsh Mohan, a well known surgical
pathologist of India, for providing pathological correlations in the book We are thankful to
Dr Sunayna Misra [M.D (Path.), PGI Chandigarh] for her valuable suggestions and inputs
especially in the pathological correlations
Preface
Trang 7Textbook of Human Histology
We extend our heartfelt thanks to Shri Jitendar P Vij (Group Chairman) and Mr Ankit Vij
(Group President) for providing us the opportunity to revise Text of Human Histology and for
their persistent support in publication of this book
Dr Sakshi Arora (Chief Development Editor), the driving force of this endeavour, deserves
a special thanks for her tireless efforts She has perservered throughout this venture with a
smile on her face We are thankful to her entire development team comprising Dr Mrinalini
Bakshi, Dr Swati Sinha, and Ms Nitasha Arora (Editors), and Mr Prabhat Ranjan, Mr Neeraj
Choudhary, Mr Ankush Sharma, Mr Phool Kumar, Mr Deep Dogra and Mr Sachin Dhawan
(Designers and Operators) for providing insights and creative ideas that helped in polishing
this book to best meet the needs of students and faculty alike
We present the 7th edition of this most popular textbook to the medical fraternity as our
tribute to a legendary anatomist, Professor Inderbir Singh for being a pillar in the education of
generations of doctors throughout the world
Neelam Vasudeva Sabita Mishra
Trang 8Colour Atlas A1–A48
Chapter 1: Light Microscopy and Tissue Preparation
Principles of a conventional bright field microscope 3
Practical tips in using a bright field microscope 5
Chapter 2: Cell Structure
Trang 9Textbook of Human Histology
Chapter 5: General Connective Tissue
Intercellular ground substance of connective tissue 71
Summary of the functions of connective tissue 78
Chapter 8: Muscular Tissue
Trang 10Contents
Chapter 10: The Blood and the Mononuclear Phagocyte System
Chapter 11: Nervous System
Tissues constituting the nervous system 162
Spinal cord; cerebellar cortex; cerebral cortex 180
Chapter 12: Skin and its Appendages
Blood vessels, lymphatics and nerves supplying blood vessels 221
Mechanisms controlling blood flow through the capillary bed 221
Trang 11Textbook of Human Histology
Chapter 14: The Respiratory System
Chapter 15: Digestive System: Oral Cavity and Related Structures
Chapter 16: Digestive System: Oesophagus, Stomach and Intestines
Distinguishing features of duodenum, jejunum, and ileum 277
Chapter 17: Hepatobiliary System and Pancreas
Trang 12Chapter 19: Male Reproductive System
Chapter 21: Endocrine System
Subdivisions of the hypophysis cerebri 367
Blood supply of the hypophysis cerebri 372
Control of secretion of hormones of the adenohypophysis 373
Trang 13Textbook of Human Histology
Some other organs having endocrine functions 385
Chapter 22: Special Senses: Eye
Chapter 23: Special Senses: Ear
Specialised end organs in the membranous labyrinth 422
Some elementary facts about the mechanism of hearing 425
Trang 14Colour Atlas
HiSTology & iTS STudy
Th e study of histology is very important for the understanding of the normal functioning of the
human body It also forms the essential basis for the study of the changes in various tissues
and organs in disease (Th is is the science of pathology) From these points of view the study
of histology is best done taking one organ system at a time Th at is the approach most teachers
prefer to take in practical classes of histology It is also the basis on which the chapters of this
book have been organised
However, in practical examinations, the emphasis is on the ability of the student to recognise
a tissue or organ that is being viewed through a microscope Here it becomes necessary to know
how to distinguish between similar looking tissues or organs belonging to diff erent systems
Th is atlas has been organised to serve this objective Tissues and organs that have a similar
appearance are considered in one lot For example, if a slide presents something that looks
like a tube, whether it be an artery or the ureter or the ductus deferens, these are considered
together Th is makes the grouping unusual, but this is exactly what the student needs at the
time of an examination
At the same time it is true that an organ can be composed of several tissues, (or layers), and
the ability to recognise them can go a long way is arriving at a correct diagnosis of the organ being
seen We will, therefore, fi rst try to study and identify the various tissues that make up diff erent
organs We will then have a good basis for identifying any organ that we are required to recognise
BASiC TiSSuES THAT CAN BE RECogNiSEd iN HiSTologiCAl SECTioNS
EPiTHEliA
Th e outer surface of the body, and the luminal surfaces of cavities (big or small) lying within
the body are lined by one or more layers of cells that completely cover them Such layers of cells
are called epithelia Epithelial tissue forms the lining of the general body surfaces, passages
and cavities within the body Basement membrane connects the epithelium to the underline
subepithelial tissues
Classifi cation of epithelial tissue is based on shape of the cells, number of cell layers and
special modifi cations seen on the cells Epithelia may be simple, when they consist of only one
layer of cells, or stratifi ed when there are several layers of cells Epithelial cells may be fl at (or
squamous), cuboidal, columnar etc
Several types of epithelia can be recognised Learning to identify an epithelium can be of
considerable help in fi nding out what organ you are seeing
Trang 15Textbook of Human Histology
Fig A1.1: An alveolus of the lung showing a lining of simple
squamous epithelium (arrows)
In surface view (Fig A1.3) the cells have polygonal outlines that interlock with those of adjoining cells
A simple squamous epithelium lines the alveoli of the lungs, the free surfaces of peritoneum, pleura and pericardium
Here it is given the name
mesothelium It also lines the
inside of blood vessels,where
it is called endothelium, and
of the heart where it is called
endocardium.
Simple Squamous Epithelium
Fig A1.2: A capillary lined by endothelium
(arrow)
Fig A1.3: Simple squamous epithelium (surface view)
Trang 16Colour Atlas
Simple Cuboidal Epithelium
Simple Columnar Epithelium
Fig A1.4: A thyroid follicle lined by simple cuboidal epithelium
In this epithelium the height of the cells is much greater than their width
Trang 17Textbook of Human Histology
Columnar Epithelium showing Striated Border
Pseudostratified Ciliated Columnar Epithelium
Fig A1.6: Columnar epithelium with a striated border in the small
a thickening with vertical striations in it: this is called a striated border
to be multi-layered However, there is actually only one layer
of cells The multi-layered appearance is due to the fact that the nuclei lie at different levels in different cells Such
an epithelium is seen in the ductus deferens
Trang 18 The deepest cells are columnar
or cuboidal The middle layers are made up of polyhedral or pear-shaped cells
Trang 19Textbook of Human Histology
Stratified Squamous Epithelium (Non-keratinised)
Stratified Squamous Epithelium (Keratinised)
Fig A1.10: Stratified squamous epithelium (non-keratinised) seen
Although this is called stratified squamous epithelium, only the most superficial cells are squamous (flattened)
Here the deeper layer are covered by additional layers that represent stages in the conversion of cells into non-living fibres This process
is called keratinisation (or cornification)
The nuclei are oval in the basal layer, rounded in the middle layer, and transversely elongated
in the superficial layers
Trang 20Colour Atlas
CoNNECTivE TiSSuE
In most organs there are areas filled in by fibres that are described as connective tissue The
main constituent of connective tissue is collagen fibres that stain pink In stretch preparations
they are seen as wavy bundles Other fibres present (elastic, reticular) can be seen with special
stains Connective tissue also contains many cells but only their nuclei can be made out
irregular Connective Tissue
Fig A2.1: Irregular connective tissue as seen in dermis of skin
Thin elastic fibres are present, but are not seen with H & E stain
Tendons are also made up of collagen fibres, but here the fibres (or fibre bundles) are arranged in orderly fashion parallel to each other
Nuclei of some cells (mainly fibroblasts) are seen between the bundles of collagen They are elongated (elliptical)
Trang 21Unlike connective tissue, that can be deformed easily, cartilage is a special form of connective
tissue that is firm, and retains its shape
Hyaline Cartilage
Fig A2.3: Adipose tissue
Fig A2.4: Hyaline cartilage
Adipose tissue is made up mainly of compactly arranged fat cells
In routine sections the cells appear empty as the fat gets dissolved during preparation
a homo-geneous matrix which separates the cells widely
Near the surface of the cartilage the cells are flattened and merge with the cells of the overlying connective tissue
This connective tissue forms the perichondrium
Costal cartilage and articular cartilage of synovial joint are example of hyaline cartilage
Key
1 Chondrocytes
2 Homogenous matrix
3 Perichondrium
Trang 22Colour Atlas
Elastic Cartilage
fibrocartilage
Fig A2.5: Elastic cartilage
Fig A2.6: Fibrocartilage
In elastic cartilage cytes are surrounded by matrix containing many elastic fi bres
chondro-
Perichondrium covering is present over the cartilage
Perichondrium is absent
Fibrocartilage is seen typically
in pubic symphysis and manubrio sternal joint
Trang 23Textbook of Human Histology
Fig A2.7: Compact bone; transverse section
Fig A2.8: Spongy (cancellous bone)
Delicate canaliculi radiate from the lacunae containing processes of osteo cytes
Interstitial lamellae fill intervals between Haversian systems
It is made up of a network of bony trabeculae (pink) in which the nuclei of some osteocytes can be seen
The spaces of the network are filled in by bone marrow in which numerous fat cells are present
The spaces between the fat cells are occupied by numerous blood forming cells (only nuclei
of which are seen)
Volkmanns canal interconnecting the adjacent haversian canal may be seen
Trang 24Fig A3.1: Longitudinal section through skeletal muscle
Fig A3.2: Longitudinal section through smooth muscle
In a longitudinal section through skeletal muscle the fibres are easily distinguished
as they show characteristic transverse striations
The muscle fibres are separated
by some connective tissue
Smooth muscle is present
in the walls of parts of the alimentary canal, in the urogenital tract etc
Key
1 Oval centrally placed nuclei
Trang 25Textbook of Human Histology
Cardiac muscle
Fig A3.3: Longitudinal section through cardiac muscle
Fig A3.4: Spinal cord A Panoramic view B Grey matter
The fibres are made up of
‘cells’ each of which has a centrally placed nucleus and transverse striations
Adjacent ‘cells’ are separated from one another by transverse lines called intercalated discs
Trang 26Colour Atlas
STRuCTuRES THAT ARE uSuAlly SEEN AS SiNglE TuBES
ARTERiES
The structure of an artery varies greatly with its size Each artery shows three layers, the tunica
intima, tunica media and the tunica adventitia (in internal to external order) The lumen is
lined by endothelium (flattened cells)
Elastic Artery
Fig A4.1: Elastic artery
Elastic artery is characterised by presence of
Tunica intima consisting of endothelium, subendothelial connective tissue and internal elastic lamina
The first layer of elastic fibres
of tunica media is considered the internal elastic lamina
Thick tunica media with many elastic fibres and some smooth muscle fibres
Tunica adventitia containing collagen fibres and vasa vasorum
Key
1 Endothelium
2 Subendothelial connective tissue
3 Internal elastic lamina
4 Tunica media
5 Tunica adventitia
Tunica intima
Trang 27Textbook of Human Histology
Fig A4.2: Muscular artery
In muscular arteries, the tunica intima is made of endothelium and internal elastic lamina (arrow) which is thrown into wavy folds due to contraction
of smooth muscle in the media
Fig A4.3: Large vein
The vein has a thinner wall and a larger lumen than the artery The tunica intima, media and adventitia can be made out, but they are not sharply demarcated The media is thin and contains only a small quantity of muscle The adventitia is relatively thick Note again that the luminal surface appears as a dark line, with
an occasional nucleus along it.
Key
1 Tunica inti ma
2 Tunica media
3 Tunica adventi ti a
Trang 28 Th e innermost layer of the mucosa, is lined by simple columnar epithelium with goblet cells and lymphocytes
Vermiform appendix can be easily recognised due to its tubular form bearing resemblance to the colon with
presence of lymphoid tissue.
Trang 29Textbook of Human Histology
uRETER
duCTuS dEfERENS
Fig A6.1: Ureter
Fig A7.1: Ductus deferens
The ureter can be recognised because it is tubular and its mucous membrane is lined by transitional epithelium
The epithelium rests on a layer
of connective tissue (lamina propria)
The mucosa shows folds that give the lumen a star shaped appearance
The muscle coat has an inner layer of longitudinal fibres and an outer layer of circular fibres This arrangement is the reverse of that in the gut
This is a tube that is distinguished from the ureter
as its mucous membrane
is lined by pseu dostratified columnar epithelium
The muscle coat is very thick Three layers, inner longitudinal, middle circular and outer longitudinal are seen
The muscle coat is surrounded
by adventitia containing blood vessels and nerves
The muscle coat is surrounded by adventitia made of fibroelastic connective tissue in which
blood vessels and fat cells are present
Trang 30 The uterine tube is characterized by presence of numerous branching mucosal folds that
almost fill the lumen of the tube
Trang 31Textbook of Human Histology
STRuCTuRES mAdE uP mAiNly of lymPHoid TiSSuE
lymPHoid TiSSuE
Lymphocytes are one variety of cells of blood Collections of them are frequently seen in
many tissues Such aggregations constitute lymphoid tissue Such tissue is seen in the form of
aggregations of dark staining nuclei Some organs (lymph nodes, spleen) are made up almost
entirely of such tissue At some sites lymphoid tissue shows nodules where the lymphocytes
are more densely packed than elsewhere The nodule may show a central area that is lighter
staining (because the cells are less densely packed)
by a zone of densely packed lymphocytes
Trang 32 Th e substance of the organ is divisible into the red pulp in which there are diff usely
distributed lymphocytes and numerous sinusoids; and the white pulp in which dense
aggregations of lymphocytes are present Th e latter are in the form of nodules surrounding
arterioles
When cut transversely the cords of spleen resemble the lymphatic nodules of lymph nodes, and like them
they have germinal centres surrounded by rings of densely packed lymphocytes However, the nodules of
the spleen are easily distinguished from those of lymph nodes because of the presence of an arteriole in
each nodule The arteriole is placed eccentrically at the margin of the germinal centre
Trang 33Textbook of Human Histology
Fig A12.1: Palatine tonsil
PAlATiNE ToNSil
Palatine tonsil is an aggregation
of lymphoid tissue that is readily recognized by the fact that it is covered by a stratified squamous epithelium on its oral surface
At places the epithelium dips into the tonsil in the form of deep crypts
Deep to the epithelium there
is diffuse lymphoid tissue
in which typical lymphatic nodules can be seen
The presence of this lobulation enables easy distinction of the thymus from all other lymphoid organs
The lobules are partially separated from each other by connective tissue
In each lobule an outer darkly stained cortex (in which lymphocytes are densely packed); and an inner lightly stained medulla (in which the cells are diffuse) are present
The medulla contains pink staining rounded masses called the corpuscles of Hassall
Key
1 Cortex
2 Medulla
3 Corpuscle of Hassall
Trang 34Colour Atlas
Fig A13.1: Thick skin
SomE STRuCTuRES CovEREd By STRATifiEd SquAmouS EPiTHElium
SKiN
The skin consists of two layers The most superficial layer is the epidermis which consists of
stratified squamous epithelium (keratinised) The epidermis rests on a thick layer of connective
tissue which is called the dermis
3 Dermis
4 Sweat glands
Thin Skin
Fig A13.2: Thin skin
Thin skin or hairy skin is characterized
by
Presence of thin epidermis made up
of keratinized stratified squamous epithelium (stratum corneum is thin)
Presence of hair follicles, sebaceous glands and sweat glands in the dermis
Trang 35 The undersurface of the tongue
is smooth, but on the dorsum the surface shows numerous projections or papillae
Each papilla has a core of connective tissue (lamina propria) covered by epithel-ium Some papillae are pointed (filiform), while others are broad at the top (fungiform)
A third type of papilla is circumvallate, the top of this papilla is broad and lies at the same level as the surrounding mucosa
The main mass of the tongue is formed by skeletal muscle seen below the lamina propria
Muscle fibres run in various directions so that some are cut longitudinally and some
transversely Numerous serous glands and mucous glands are present amongst the muscle
fibres
Key
P Papillae 2 Lamina propria
1 Stratified squamous epithelium 3 Skeletal muscle
Trang 36Colour Atlas
oESoPHAguS
Fig A15.1: Oesophagus (Low power)
Fig A15.2: Oesophagus (High power)
In transverse section the oesophagus shows the following layers (from within outwards):
Lining of non-keratinised stratified squamous epithe-lium
The lining epithelium, lamina propria and muscularis mucosa collectively constitute the mucosa
The submucosa having oesophageal glands (mucous secreting)
The layer of circular muscle, and the layer of longitudinal muscle constituting the muscularis externa
muscle is of the striated variety in the upper one third of the oesophagus, mixed in the middle one third, and smooth in the lower one third.
Trang 37Textbook of Human Histology
Fig A22.1: Vagina
Th e vagina is a fi bromuscular structure consisting of an inner mucosa, a middle muscular layer and an outer adventitia
Th e mucosa consists of Stratifi ed squamous non-keratinised epithelium
Loose fi broelastic connective tissue (lamina propria) with many blood vessels and no glands
Th e mucosa of vagina is rich
in glycogen and hence stains palely which distinguishes it from oesophagus
Muscular layer consists of smooth muscle fi bres
vAgiNA
The structure of the vagina has a superfi cial resemblance to that of the urinary bladder However, the two can
be distinguished by the fact that the mucosa of the vagina is lined by stratifi ed squamous epithelium
Trang 38Colour Atlas
CoRNEA
Fig A16.1: Cornea
The cornea is made up of five layers
Most of the thickness of the cornea is formed by the substantia propria (or corneal stroma)
made up of collagen fibres embedded in a ground substance
Deep to the substantia propria there is a thin homogeneous layer called the posterior
limiting lamina
The posterior surface of the cornea is lined by a single layer of flattened or cuboidal cells
Trang 39Textbook of Human Histology
SomE oRgANS iN wHiCH TiSSuES ARE ARRANgEd iN PRomiNENT lAyERS
In this group we will consider organs that have a thick wall and a fairly large lumen Some of
these are tubular, but as the tube has a large diameter, only part of it is seen in a section The
wall in most of these organs is made up of an inner mucosa, a submucosa and layers of muscle
One such organ, the oesophagus, has already been seen in Fig A15.1 The vermiform appendix
(Fig A5.1) also has a similar structure
STomACH
Fig A17.1: Stomach
The basic structure of stomach
is similar to oesophagus i.e it
is composed of (from within outwards):
Muscularis externa is composed of three layers of smooth muscle–inner oblique, middle
circular and outer longitudinal
Trang 40 Mucosa is made of simple columnar absorptive epithelium with goblet cells The epithelium
and the underlying lamina propria shows finger-like evaginations called intestinal villi
Epithelium also shows tubular invagination from the base of the villi into the lamina propria
known as crypts of Lieberkuhn (intestinal glands) These crypts are lined by columnar and
goblet cells
Lamina propria consisting of connective tissue
Muscularis mucosa is made of smooth muscle fibres This layer is responsible for
movement and folding of mucosa
Submucosa shows presence of Brunner's gland in duodenum and Peyer's patches in ileum
Muscularis externa and serosa corresponds exactly with stomach
Fig A18.1: Small intestine
JEJuNum
The structure of jejunum should
be regarded as typical for small intestine