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B. J. MEDICAL COLLEGE
CLASS HISTOLOGY
Guideline of Basic Histology
CLASS HISTOLOGY
Guideline of Basic Histology
B. J. MEDICAL COLLEGE
: Makers :
Aaditya Muniya
Student of 2nd year 1st term M.B.B.S.
&
Chintan Makwana
Student of 2nd year 1st term M.B.B.S.
IMPORTANT DECLARATION
Kindly note one thing that photographs of
ideal slide which are given in this booklet, are
taken from Inderbir singh`s Textbook of
Human Histology 7th edition and Difiore`s
Atlas of Histology 11th edition.
This booklet is not for sell.
Our aim for making this booklet is :
1. To understand the basic human histology.
2. To draw histologically correct diagrams in
your journal and all anatomy exam.
3. To identify the histology slide in your lab
and practical exam.
This booklet is only for students of 1st year
M.B.B.S.
This booklet doesn’t comparable with any
other authorized books and journals.
This booklet just gives an guideline about
basic histology.
Dedicated to ……
“All
Our
Lovely
Juniors .”
Plate 1 : SEROUS GLAND
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINT :
1. Triangular cells with rounded nuclei.
2. Their nuclei are centrally placed.
3. Cell boundaries are indistinct.
4. Lumen of these acini is smaller than the mucous acini.
Plate 2 : MUCOUS GLAND
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Tall cells with flat nuclei at their base.
2. Cell boundaries are distinct.
3. Lumen of these acini is larger than the serous acini.
4. Lightly stained and appear empty with H & E staining.
Plate 3 : MIXED GLAND
DRAWING :
Plate 4 : LOOSE AREOLAR TISSUE
DRAWING :
IDEAL SLIDE :
Plate 5 : ADIPOSE TISSUE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The cytoplasm of each cell is seen as a pink rim.
2. The nucleus is flat and lies to one side(eccentric).
3. In routine sections, the cells appear empty, giving it a
honeycomb appearance.
Plate 6 : MUCOID TISSUE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Component of mucoid tissue is a jelly like group
substance rich in hyaluronic acid.
2. Scattered and star-shaped fibroblasts, some delicate
collagen fibers and some rounded cells.
Plate 7 : Longitudinal Section OF TENDON
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Presence of collagen fibers arranged in orderly fashion
parallel to each other.
2. In longitudinal section of tendon, the fibroblasts and
their nuclei are seen to be elongated.
3. Ground substance is less in amount.
Plate 8 : Transverse Section OF TENDON
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. In transverse sections, the fibroblasts are stellate
shaped.
2. Ground substance is less in amount.
Plate 9 : RETICULAR TISSUE
DRAWING :
IDENTIFICATION POINTS :
1. It contain abundant reticular fibres.
2. Reticular fibres are composed of collagen type 3.
3. They differ from typical collagen fibres as follow :
 They are much finer and have uneven thickness.
 They form a network by branching, and by
anastomosing with each other.
 Reticular fibres stained black with silver
impregnation but type 1 collagen fibres stained
brown with silver impregnation.
Plate 10 : HYALINE CARTILAGE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. There is presence of isogenous cell groups of
chondrocytes called as cell nest.
2. Its intercellular substance appears to be
homogenous.
3. In H & E staining, the matrix is stained blue.
4. Around cell nests, the matrix stains deeper than
elsewhere is called the territorial matrix or lacunar
capsule.
5. The pale staining matrix separating cell nests is the
interstitial matrix.
6. Chondrocytes increases in size from periphery to
centre.
7. 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.
8. Using special techniques, it can be shown that many
collagen fibres are present in the matrix.
Plate 11 : ELASTIC CARTILAGE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The main difference between hyaline cartilage and
elastic cartilage is that instead of collagen fibres, the
matrix contains numerous elastic fibres that form a
network.
2. The elastic fibres are difficult to see in H & E stained
sections, but they can be clearly visualised if special
methods for staining elastic fibres are used.
3. Elastic cartilage is characterised by presence of
chondrocytes within lacuna surrounded by bundles
of elastic fibres.
Plate 12 : FIBROCARTILAGE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Presence of prominent collagen fibres arranged in
bundles with rows of chondrocytes intervening
between the bundles.
2. Perichondrium is absent.
3. This kind of cartilage can be confused with the
appearance of a tendon. However, the chondrocytes
in fibrocartilage are rounded but in a tendon,
fibrocytes are flattened and elongated.
4. The collagen in fibrocartilage is different from that in
hyaline cartilage in that it is type 1 collagen and not
type 2.
Plate 13 : Transverse Section OF COMPACT BONE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. A transverse section through compact bone shows
ring-like osteons.
2. At the centre of each osteon there is a haversian
canal.
3. Around the canal there are concentric lamellae of
bone amongst which there are small spaces called
lacunae.
4. Delicate canaliculi radiate from the lacunae, these
contain cytoplasmic processes of osteocytes.
5. Interstitial lamellae fill intervals between haversian
systems.
6. Near the surface of compact bone, the lamellae are
arranged in a parallel manner. These are
circumferential lamellae.
7. Volkmann`s canal interconnecting the adjacent
haversian canal may be seen.
Plate 14 : Longitudinal Section OF
COMPACT BONE
DRAWING :
IDEAL SLIDE :
Plate 15 : DEVELOPING BONE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. In the zone of resting cartilage, the cells are small
and irregularly arranged.
2. In the zone of proliferative cartilage, the cells are
larger and undergo repeated mitosis.
3. As they multiply, they come to be arranged in
parallel columns, separated by bars of intercellular
matrix.
4. In the zone of calcification, the cells become still
larger and the matrix becomes calcified.
5. Next to the zone of calcification, there is zone where
cartilage cells are dead and the calcified matrix is
being replaced by bone.
Plate 16 : Longitudinal Section OF
SKELETON MUSCLE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. In a longitudinal section through skeleton muscle,
the fibres are easily distinguished as they show
characteristic transverse striations.
2. The fibres are long and parallel without branching.
3. Many flat nuclei are placed at the periphery.
4. The muscle fibres are separated by some
connective tissue.
Plate 17 : Transverse Section OF
SKELETON MUSCLE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Fibres seen as irregularly round structures with
peripheral nuclei.
2. Muscle fibres grouped into numerous fasciculi.
3. Dots within the fibres are myofibrils which are seen
at higher magnification.
4. The connective tissue of the muscle consists of :
 Epimysium : connective tissue sheath of muscle.
 Perimysium : connective tissue covering of each
fascicle.
 Endomysium : loose connective tissue surrounding
each muscle fibre.
Plate 18 : CARDIAC MUSCLE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The fibres of cardiac muscle do not run in strict
parallel formation, but branch and anastomose with
other fibres to form a network.
2. Each fibre of cardiac muscle is not a multinucleated
syncytium as in skeleton muscle , but is a chain of
cardiac muscle cells each having its own nucleus.
3. The nucleus of each myocyte is located centrally and
not peripherally as in skeleton muscle.
4. The myofibrils and striations of cardiac muscle are
not as distinct as those of skeleton muscle.
5. With the light microscope the junctions between
adjoining cardiac myocytes are seen as dark staining
transverse lines running across the fibres, but are
broken into a number of ‘steps’.
Plate 19 : SMOOTH MUSCLE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. It is fusiform/spindle shaped cells having broad
central part and tapering ends.
2. The nucleus, which is oval or elongated, lies in the
central part of the cell.
3. With the light microscope, the sarcoplasm appears
to have indistinct longitudinal striations but there
are no transverse striations.
4. In such a layer, the cells are so arranged that the
thick central part of one cell is opposite the thin
tapering ends of adjoining cells.
5. In longitudinal section, the nucleus is elongated and
centrally placed.
6. In transverse section, the nucleus is seen in those
cells which are cut through the centre but others do
not show nuclei.
Plate 20 : DIFFERENT TYPES OF NEURONS
AND NEUROGLIA CELLS
TYPES OF NEURONS :
1. Unipolar neuron
2. Bipolar neuron
3. Pseudo unipolar neuron
4. Multipolar neuron
TYPES OF NEUROGLIA CELLS :
1. Ependymal cell
2. Microglia
3. Protoplasmic astrocyte
4. Fibrous astrocyte
5. Oligodendrocyte
Plate 21 : PERIPHERAL NERVE
DRAWING : (H & E STAINING)
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. In a longitudinal section of peripheral nerve, the
central axons appear as slender threads stained lightly
with H & E staining.
2. In a longitudinal section, the individual axons usually
follow a characteristic wavy pattern.
3. Located among the wavy axons in the nerve fascicle
are numerous nuclei of the schwann cells and
fibrocytes of the endoneurium.
4. However, it is often difficult to distinguish between the
nuclei of schwann cells and the fibrocytes of the
endoneurium.
5. In a transverse section, the axons appear as thin, dark
central structures, surrounded by the dissolved
remnants of myelin.
Plate 22 : LYMPH NODE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. A thin capsule surrounds the lymph node and sends in
trabeculae.
2. Just beneath the capsule a clear space is seen. This is
subcapsular sinus.
3. A lymph node has an outer cortex and a inner medulla.
4. The cortex is packed with lymphocytes. A number of
rounded lymphatic follicles are present.
5. Each nodule has a pale staining germinal centre
surrounded by a zone of densely packed lymphocytes.
6. Within the medulla the lymphocytes are arranged in
the form of anastomosing cords.
7. Several blood vessels can be seen in the medulla.
Plate 23 : SPLEEN
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The spleen is characterised by a thick capsule with
trabeculae extending from it into the organ.
2. The substance of the organ is divisible into the red pulp
in which there are diffusely distributed lymphocytes
and numerous sinusoids and the white pulp in which
dense aggregation of lymphocytes are present. The
latter are in the form of cords surrounding arterioles.
3. When cut transversely, the cords resemble the
lymphatic nodules of lymph nodes and like them they
have germinal centres surrounded by rings of densely
packed lymphocytes.
4. The nodules of the spleen are easily distinguished from
those of lymph nodes because of the presence of an
arterioles in each nodules.
5. This arterioles occupies an eccentric position in the
nodules.
6. More than one arteriole may be present in relation to
one germinal centre.
Plate 24 : THYMUS
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The thymus is made up of lymphoid tissue arranged in
the form of distinct lobules.
2. The presence of this lobulation enables easy distinction
of the thymus from all other lymphoid organs.
3. The lobules are partially separated from each other by
connective tissue septae.
4. In each lobule an outer darkly stained cortex and an
inner lightly stained medulla are present.
5. Whereas the cortex is confined to one lobule, the
medulla is continuous from one lobule to another.
6. The medulla contains pink staining rounded masses
called the corpuscles of Hassall.
Plate 25 : PALATINE TONSIL
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Palatine tonsil is an aggregation of lymphoid tissue that
is readily recognised by the fact that it is covered by a
stratified squamous epithelium.
2. At places the epithelium dips into the tonsil in the form
of deep crypts.
3. Deep to the epithelium, there is diffuse lymphoid
tissue in which typical lymphatic nodules can be seen.
Plate 26 : ELASTIC ARTERY
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Tunica intima consisting of endothelium, sub
endothelium connective tissue and internal elastic
lamina.
2. The first layer of elastic fibres is called the internal
elastic lamina.
3. The internal elastic lamina is not distinct from the
elastic fibres of media.
4. Well developed sub endothelial layer in tunica intima.
5. Thick tunica media with many elastic fibres and some
smooth muscle fibres.
6. Tunica adventitia containing collagen fibres with
several elastic fibres.
Plate 27 : MUSCULAR ARTERY
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. In tunica intima, the internal elastic lamina in the
muscular arteries stands out distinctly from the
muscular media and it is thrown into wavy folds due to
contraction of smooth muscle in the media.
2. Tunica media is made up mainly of smooth muscles.
3. Between groups of muscle fibres some connective
tissue is present, which may contain some elastic
fibres.
4. Tunica adventitia contains collagen fibres and few
elastic fibres.
Plate 28 : VEIN
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The tunica media contains a much larger quantity of
collagen than in arteries.
2. In arteries, the tunica media is usually thicker than
the adventitia. In contrast the adventitia of veins is
thicker than the media.
3. A clear distinction between the tunica intima, media
and adventitia cannot be made out in small veins as
all these layers consist predominantly of fibrous
tissue.
Plate 29 : SINUSOIDS & CAPILLARY
DRAWING :
Plate 30 : ARTERIOLE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Muscular arterioles can be distinguished from true
arteries :
 By their small diameter.
 They do not have an internal elastic lamina. They
have a few layers of smooth muscle in their
media.
2. Terminal arterioles can be distinguished from
muscular arterioles as follow :
 They have a diameter less than 50 micro meter.
 They have only a thin layer of muscle in their
walls.
3. All the three layers, i.e., tunica adventitia, tunica
media and tunica intima are thin as compared to
arteries.
Plate 31 : THIN SKIN
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Stratum corneum of epidermis is thin.
2. Stratum lucidum of epidermis is absent.
3. Epidermal ridges are absent.
4. Hair follicles, arrector pilli muscle and sebaceous
glands are present.
5. Sweat glands in the dermis are few.
Plate 32 : NAIL
DRAWING :
Plate 33 : THICK SKIN
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Stratum corneum of epidermis is very thick.
2. Stratum lucidum of epidermis is present.
3. Epidermal ridges are well developed.
4. Hair follicles, arrector pilli muscle and sebaceous
glands are absent.
Plate 34 : OLFACTORY & RESPIRATORY
EPITHELIUM
DRAWING :
IDEAL SLIDE :
Plate 35 : TRACHEA
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Mucosa is formed by pseudostratified ciliated
columnar epithelium with goblet cells, basal cells and
the underlying lamina propria.
2. Submucosa made up of loose connective tissue
containing mucous gland, serous gland and numerous
aggregation of lymphoid tissue.
3. C-shaped mass of hyaline cartilage is present.
4. The connective tissue in the wall of the trachea
contains many elastic fibres.
5. Adventitia is made of fibroelastic connective tissue
containing blood vessels and nerves.
Plate 36 : EPIGLOTTIS
DRWING :
IDENTIFICATION POINTS :
1. The surface of epiglottis is covered on oral side by
stratified squmous epithelium and on respiratory side
by pseudostratified ciliated columnar epithelium.
2. The core of the epiglottis is made up of a plate of
elastic cartilage covered by connective tissue in which
there are numerous blood vessels and mucous glands.
Plate 37 : LUNG
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The lung surface is covered by pleura. It consists of a
lining of mesothelium resting on a layer of
connective tissue.
2. The lung parenchyma is made up of numerous thinwalled spaces or alveoli.
3. The alveoli give a honey comb appearance and are
lined by flattened squamous cells. They are filled
with air.
4. The intrapulmonary bronchus is lined by
pseudostratified ciliated columnar epithelium with
few goblet cells. Its structure is similar to trachea i.e.
it has smooth muscles, cartilage and glands present
in its wall.
5. The bronchiole is lined by simple columnar or
cuboidal epithelium surrounded by bundles of
smooth muscle cells.
6. Bronchioles subdivide and when their diameter is
approximately 1mm or less, they are called terminal
bronchiole.
7. Respiratory bronchiole, alveolar duct and atrium are
also present.
Plate 38 : BRONCHUS
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Bronchus is lined by pseudostratified ciliated
columnar epithelium.
2. The cartilage in the wall of the bronchus become
irregular in shape, and is progressively smaller.
3. The amount of muscle in the bronchial wall increases
as the bronchus become smaller.
4. Both serous and mucous acini present between
cartilage and muscle layer.
Plate 39 : LIP
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The substance of the lip is formed by a mass of muscle.
2. Each lip has an ‘external’ surface covered by skin and
an ‘internal’ surface lined by mucous membrane.
3. The ‘external’ surface of the lip is lined by true skin in
which hair follicles and sebaceous glands can be seen.
4. The mucous membrane is lined by stratified squamous
nonkeratinised epithelium.
5. The epithelium has a well marked rete ridge system.
The term rete ridges is applied to finger like projections
of epithelium that extend into underlying connective
tissue, just like the epidermal papillae.
Plate 40 : TONGUE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The tongue is covered on both surfaces by nonkeratinised stratified squamous epithelium.
2. The ventral surface of the tongue is smooth, but on
the dorsum the surface shows numerous projections
or papillae.
3. Each papillae has a core of connective tissue covered
by epithelium. 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.
4. 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.
5. Numerous serous and mucous glands are present
amongst the muscle fibres.
Plate 41 : CIRCUMVALLATE PAPILLA
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. In sections through the papilla it is seen that papilla
has a circumferential ‘lateral wall’ that lies in the depth
of the groove.
2. They are characterised by their dome-shaped structure
lined stratified squamous epithelium.
3. Numerous oval shaped lightly stained taste buds can
be seen on the lateral wall of the papillae.
4. Ducts of serous gland of Von Ebner is open in groove
around the papilla.
5. Skeleton muscle can be seen extending into the
papillae.
Plate 42 : GROUND SECTION OF TEETH
IDEAL SLIDE :
Plate 43 : OESOPHAGUS
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The mucous membrane of the oesophagus shows
several longitudinal folds.
2. The mucosa is lined by non-keratinised stratified
squamous epithelium.
3. Finger like processes of the connective tissue of the
lamina propria project into the epithelial layer.
4. At the upper and lower ends of the oesophagus some
tubuloalveolar mucous glands are present in the
lamina propria.
5. The muscularis mucosae is absent or poorly developed
in the upper part of the oesophagus. It is distinct in the
lower part of the oesophagus.
6. The only special feature of the submucosa is the
presence of compound tubuloalveolar mucous glands.
Small aggregations of lymphoid tissue may be present
in the submucosa.
7. The muscle layer consists of the usual circular and
longitudinal layers. However, it is unusual in that the
muscle fibres are partly striated and partly smooth.
8. The muscle layer of the oesophagus is surrounded by
dense fibrous tissue that forms an adventitial coat for
the oesophagus.
Plate 44 : CARDIAC PART OF STOMACH
DRAWING :
IDENTIFICATION POINTS :
1. At low magnification, the cardiac end of stomach
shows all the four layers seen in stomach :
 Mucosa
 Submucosa
 Muscularis externa
 Serosa
2. At its cardiac end the stomach is lined by simple
columnar cells. The epithelium is sharply demarcated
from the stratified squamous epithelium lining the
lower end of the oesophagus.
3. Important distinguishing points of cardiac end of
stomach are the columnar epithelium lining, the
absence of goblet cells, and the simple tubular nature
of cardiac glands.
Plate 45 : FUNDUS PART OF STOMACH
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. Mucosa is lined by simple tall columnar epithelium. It
shows invaginations called gastric pits that occupy the
superficial one fourth of the mucosa.
2. The area between pits and the muscularis mucosae is
packed with tubular gastric glands.
3. The glands are lined mainly by blue staining chief cells
or peptic cells. Amongst these there are pink staining
oxyntic cells. These are large cells that are placed
peripherally in the wall of the gland. They are more
numerous in the upper parts of the gastric glands.
4. Muscularis externa is composed of three layers of
smooth muscle- inner oblique , middle circular and
outer longitudinal.
5. Observe that the gastric pits occupy the upper one
fourth of the lamina propria of mucosa.
Plate 46 : PYLORIC PART OF THE STOMACH
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. In the pyloric part of the stomach the gastric pits are
much deeper than in the body of the stomach.
2. Deep to the pits, there are pyloric glands that are
lined by mucous secreting cells. These are pale
staining.
3. The muscularis mucosae, submucosa, and part of the
muscle coat are also seen.
4. It is important to note that the stomach does not
have villi. In the photomicrograph folds of epithelial
lining may be confused with villi.
5. Observe that each fold merges with underlying
connective tissue completely. When true villi are
present , small parts of them appear as circular or
oval masses not attached to a villus or to the
submucosa . these are villi that have been cut
transversely or obliquely.
6. Another important feature to note is that the lining
epithelium does not have typical goblet cells, but
some epithelial cells are mucous secreting.
Plate 47 : DUODENUM
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The mucosa consists of :
 Numerous finger-like processes, or villi, that project
from the surface of the mucosa into the lumen.
 Numerous depressions or crypts that invade the
lamina propria.
2. The duodenum is easily distinguished from the jejunum
or ileum because of the presence of glands in the
submucosa. (No glands are present in the submucosa
of the jejunum or ileum)
3. These duodenal glands of Brunner are compound
tubule-alveolar glands.
4. Their ducts pass through the muscularis mucosae to
open into the intestinal crypts of Lieberkuhn.
5. The cells lining the alveoli of duodenal glands are
predominantly mucous secreting columnar cells having
flattened basal nuclei.
Plate 48 : JEJUNUM
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The Jejunum is distinguishing from the ileum by
following points :
 A larger diameter
 A thicker wall
 Larger and more numerous circular folds
 Larger villi
 Fewer solitary lymphoid follicles. Aggregated
lymphoid follicles are absent in the proximal
jejunum, and small in the distal jejunum
2. The mucosa consists of :
 Numerous finger-like processes, or villi, that project
from the surface of the mucosa into the lumen.
 Numerous depressions or crypts that invade the
lamina propria
3. Some goblet cells also seen in the section of the
jejunum.
Plate 49 : ILEUM
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The general structure of the ileum is similar to that of
the jejunum except for :
 The entire thickness of the lamina propria is in
filtrated with lymphocytes amongst which typical
lymphatic follicles can be seen which may extend
into the submucosa. These lymphatic follicles are
called as Peyer`s patches.
 In the region overlying the Peyer`s patch villi may be
rudimentary or absent.
2. The villi are thin and slender in the region of ileum.
3. M cells are found overlying the lymphoid follicles.
Plate 50 : COLON
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The most important feature to note is the absence of
villi.
2. The mucosa shows numerous tubular glands or crypts.
The surface of the mucosa , and the crypts, are lined by
columnar cells amongst which there are numerous
goblet cells.
3. A section of the large intestine is easily distinguished
from that of the small intestine because of the absence
of villi; and from the stomach because of the presence
of goblet cells (which are absent in the stomach)
4. The muscularis mucosa, submucosa and circular muscle
coat are similar to those in the small intestine.
5. However, the longitudinal muscle coat is gathered into
three thick bands called taenia coli. The longitudinal
muscle is thin in the intervals between the taenia.
Plate 51 : APPENDIX
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The appendix is the narrowest part of the
gastrointestinal canal and is seen as a tubular
structure.
2. The inner most layer of the mucosa, is lined by simple
columnar epithelium with goblet cells.
3. The crypts are poorly formed.
4. Scattered lymphocytes and aggregated nodules are
present in the lamina propria and they may extend into
the next layer.
5. The next layer, submucosa may show a variable
number of lymphatic nodules.
6. The submucosa is surrounded by smooth muscle layer
followed by serosa.
7. The longitudinal muscle coat is complete and equally
thick all round. Taenia coli are not present.
Plate 52 : LIVER
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The view of Liver shows many hexagonal areas called
hepatic lobules. The lobules are partially separated by
connective tissue.
2. Each lobule has a small round space in the centre. This
is the central vein.
3. A number of broad irregular cords of cells seem to pass
from this vein to the periphery of the lobule. These
cords are made up of polygonal liver cells- hepatocytes.
4. The cords are separated from each other by spaces
called sinusoids.
5. The sinusoids are lined by endothelial cells and kupffer
cells (macrophage cells).
6. Along the periphery of the lobules there are angular
intervals filled by connective tissue.
7. Each such area contains a branch of the portal vein, a
branch of the hepatic artery, and an interlobular bile
duct.
8. These three constitute portal triad. The identification
of hepatic lobules and of portal triads is enough to
recognise liver tissue.
Plate 53 : GALL BLADDER
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The mucous membrane is lined by tall columnar cells
with striated border.
2. The mucosa is highly folded and some of the folds
might look like villi.
3. Crypts may be found in lamina propria.
4. Submucosa is absent.
5. The muscle coat is poorly developed there being
numerous connective tissue fibres amongst the muscle
fibres. This is called as fibro muscular coat.
6. A serous covering lined by flattened mesothelium is
seen.
7. Gall bladder can be differentiated from small intestine
by Absence of villi
 Absence of goblet cells
 Absence of submucosa
 Absence of proper muscularis externa
Plate 54 : PANCREAS
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. This is a gland made up of serous acini.
2. The lumen of the acinus is very small.
3. In section stained with H & E , the cytoplasm of acinar
cell is highly basophilic particularly in the basal part.
4. Numerous secretory granules can be demonstrated in
the cytoplasm, specially in the apical part of the cell.
These granules are eosinophilic.
5. Some acini may show pale staining centroacinar cell in
the centre.
6. Centroacinar cell really belong to the intercalated
ducts.
7. Amongst the acini some ducts are seen.
8. The ducts have a distinct lumen, lined by cuboidal
epithelium.
9. At some places, the acini are separated by areas where
we see aggregation of cells quite different from those
of the acini.
10.
These aggregations form the pancreatic islets, pale
staining cells arranged as groups, surrounded by blood
vessels.
Plate 55 : RENAL CORTEX
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The kidney is covered by capsule.
2. Deep to the capsule, there is the cortex.
3. In the cortex, we see circular structure called renal
corpuscles surrounding which there are tubules cut in
various shapes.
4. The dark pink stained tubules are parts of the proximal
convulated tubules, there lumen is small and indistinct.
It is lined by cuboidal epithelium with brush border.
5. Lighter staining tubules, each with a distinct lumen, are
the distal convulated tubules, they are lined by simple
cuboidal epithelium.
6. PCT are more in number than DCT.
Plate 56 : RENAL MEDULLA
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. A high power view of a part of the renal medulla shows
a number of collecting ducts cut transversely or
longitudinally.
2. They are lined by a cuboidal epithelium, the cells of
which stain lightly. Cell boundaries are usually distinct.
The lumen of the tubules is also distinct.
3. Sections of the thin segment of the loop of Henle are
seen. They are lined by flattened cells, the walls being
very similar in appearance to those of blood very
capillaries.
4. Sections through the thick segments of loops of Henle
are seen. They are lined by cuboidal epithelium.
 NOTE : When we look at a section of the kidney we see
that most of the area is filled with a very large number
of tubules. These are of various shapes and have
different types of epithelial lining. This fact by itself
suggests that the tissue is the kidney.
Plate 57 : URETER
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The Ureter can be recognised because it is tubular and
its mucous membrane is lined by transitional
epithelium.
2. The epithelium rests on a lamina propria.
3. The mucosa shows folds that give the lumen a starshaped appearance.
4. 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.
5. The muscle coat is surrounded by connective tissueadventitia in which blood vessels and fat cells are
present.
6. The ureter is differentiate from ductus deferens by thin
muscle coat and presence of transitional epithelium.
Plate 58 : URINARY BLADDER
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The mucous membrane is lined by transitional
epithelium. There is no muscularis mucosae.
2. In the empty bladder the mucous membrane is thrown
into numerous folds that disappear when the bladder
is distended.
3. The muscle layer is thick. The smooth muscle in it
forms a meshwork. Internally and externally the fibres
tend to be longitudinal. In between them there is a
thicker layer of circular fibres.
4. The distinct muscle layers may not be distinguishable.
Plate 59 : URETHRA
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The mucous membrane consists of a pseudostratified
columnar epithelium. A short part adjoining the urinary
bladder is lined by transitional epithelium, while the
part near the external orifice is lined by stratified
squamous epithelium.
2. The submucosa consists of loose connective tissue.
3. The muscle coat consists of an inner longitudinal layer
and an outer circular layer of smooth muscle. This coat
is better defined in the female urethra. In the male
urethra, it is well defined only in the membranous and
prostatic parts.
Plate 60 : TESTIS
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The testis has an outer fibrous layer, the tunica
albuginea deep to which :
 A number of seminiferous tubules cut in various
directions are seen.
 The tubules are separated by connective tissue,
containing blood vessels and groups of interstitial
cells of Leydig.
 Each seminiferous tubule is lined by several layers of
cells.
 Cells are of two types :
o Spermatogenic cells which produce spermatozoa,
o Sustentacular (Sertoli) cells which have a
supportive function.
2. Details of cells lining a seminiferous tubule seen at a
high magnification :
i) The outer most row of nuclei belongs to
sustentacular cells and to spermatogonia.
ii) Passing inwards towards the centre of the tubule we
have large darkly staining nuclei of spermatocytes,
and many smaller nuclei of spermatids.
iii) Towards the centre of the tubule a number of
developing spermatozoa are seen.
3. In the practical class you may not be able to recognise
these cells. Observe that the presence of many cells
located at different levels gives the appearance of a
stratified epithelium which are actually the
spermatogonia at different stages of maturation.
Plate 61 : EPIDIDYMIS
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The duct is lined by pseudostratified columnar
epithelium which is made of 2 types of cells tall
columnar cells, and shorter basal cells that do not
reach the lumen.
2. The luminal surface of each columnar cell bears nonmotile projections that resemble cilia. They do not
have the structure of true cilia.
3. The basal cells are precursors of the tall cells.
4. Beneath the epithelium there is a layer of circularly
arranged smooth muscle fibres. This muscle layer
increases in thickness gradually from head to tail.
Plate 62 : DUCTUS DEFERENS
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The mucous membrane shows a number of
longitudinal folds so that lumen appears to be stellate
in section.
2. The lining epithelium is simple columnar, but becomes
pseudostratified columnar in the distal part of the
duct.
3. The epithelium is supported by a lamina propria.
4. The muscle coat is very thick and consists of smooth
muscle. It is arranged in the form of an inner circular
layer and outer longitudinal layer.
5. The fibroelastic connective tissue forms the adventitial
layer containing blood vessels and nerves.
Plate 63 : SEMINAL VESICLE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The mucous lining is thrown into numerous thin folds
that branch and anastomose. The lining epithelium is
simple columnar, or pseudostratified. Goblet cells are
present in the epithelium.
2. The seminal vesicles consists of a thin intermediate
layer of smooth muscles. The muscle layer contains
outer longitudinal and inner circular fibres.
3. The outer covering of loose connective tissue forms the
adventitial layer containing blood vessels and nerves.
Plate 64 : PROSTATE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The prostate consists of glandular tissue embedded in
prominent fibromuscular stroma.
2. The glandular tissue is in the form of follicles with
serrated edges. They are lined by columnar epithelium.
The lumen may contain amyloid bodies.
3. The amyloid bodies or corpora amylacea are more
abundant in older individuals. These consist of
condensed glycoprotein.
4. The follicles are separated by broad bands of
fibromuscular tissue.
Plate 65 : PENIS
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The penis is covered all round by thin skin that is
attached loosely to underlying tissue.
2. The substance of the penis is made up of three masses
of erectile tissue. The dorsal masses are the right and
left corpora cavernosa, while the ventral mass is the
corpus spongiosum.
3. The corpus spongiosum is traversed by the penile
urethra throughout its length.
4. The tip of urethra at glans penis is lined by stratified
squamous non-keratinised epithelium.
5. Many small mucous glands of Littre are scattered along
the length of urethra that secrete mucus.
Plate 66 : OVARY
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The surface is covered by a cuboidal epithelium. Deep
to the epithelium there is a layer of connective tissue
that constitutes the tunica albuginea.
2. The substance of the ovary has an outer cortex in
which follicles of various sizes are present; and an
inner medulla consisting of connective tissue
containing numerous blood vessels.
3. Just deep to the tunica albuginea many primordial
follicles each of which contains a developing ovum
surrounded by flattened follicular cells are present.
4. Large follicles have a follicular cavity surrounded by
several layers of follicular cells.
5. The cells surrounding the ovum constitute the cumulus
oophoricus.
6. The follicle is surrounded by a condensation of
connective tissue which forms a capsule for it.
7. The capsule consists of an inner cellular part, and an
outer fibrous part collectively called as theca folliculi.
The follicle is surrounded by a stroma made up of
reticular fibres and fusiform cells.
Plate 67 : UTERUS IN PROLIFERATIVE PHASE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. The wall of the uterus consists of a mucous membrane
(called the endometrium) and a very thick layer of
muscle(the myometrium). The thickness of the muscle
layer helps to identify the uterus easily.
2. The endometrium has a lining of columnar epithelium
that rests on a stroma of connective tissue.
3. Numerous tubular uterine glands dip into the stroma.
4. The appearance of the endometrium varies
considerably depending upon the phase of the
menstrual cycle
 The endometrium is thin and progressively
increases in thickness.
 The uterine glands are straight and tubular in this
phase.
Plate 68 : UTERUS IN SECRETORY PHASE
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1. In the secretory phase :
 The thickness of the endometrium is much
increased.
 The uterine glands elongate, become dilated, and
tortuous as a result of which they have
sawtoothed margins in sections.
 Blood vessels extend in the upper portion of
endometrium.
2. In this phase the appearance of the endometrium
becomes so distinctive that the uterus cannot be
confused with any other organ.
Plate 69 : VAGINA
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
 The mucous membrane shows numerous longitudinal
folds, and is firmly fixed to the underlying muscle layer.
It is lined by non-keratinised stratified squamous
epithelium.
 No glands are seen in the mucosa. The mucosa of
vagina is rich in glycogen and hence the cells are pale
stained which distinguishes it from oesophagus.
 The muscle coat is made up of an outer layer of
longitudinal fibres, and a much thinner inner layer of
circular fibres.
 The muscle wall is surrounded by an adventitia made
up of fibrous tissue containing many elastic fibres.
Plate 70 : PLACENTA
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
 A slide of placenta shows numerous chorionic villi.
 A villus is lined with inner cytotrophoblasts and outer
syncytiotrophoblasts.
 Cytotrophoblasts are cuboidal in shape.
 Syncytiotrophoblasts layer is consists of
multinucleated cytoplasm with indistinct cell margins.
 Core of villi contains umbilical blood capillaries
embedded in thin layers of foetal connective tissue.
 Cross sections of villi are surrounded by maternal
blood.
Plate 71 : UMBILICAL CORD
DRAWING :
IDENTIFICATION POINTS :
 It contains two umbilical arteries, which carries
deoxygenated blood from foetus to placenta.
 It also contains one umbilical vein, which carries
oxygenated blood from placenta to foetus.
 Amniotic membrane lined by flattened epithelial cells.
 Deep to amniotic membrane, mucoid connective
tissue [Wharton`s Jelly] is present which contains
fibroblasts, collagen fibres and ground substance.
Plate 72 : INACTIVE MAMMARY GLAND
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
 Mammery gland consists of lobules of glandular tissue
separated by considerable quantity of connective
tissue and fat.
 Non lactating mammary glands contain more
connective tissue and less glandular tissue.
 The glandular elements or alveoli are distinctly
tubular. They are lined by cuboidal epithelium and
have a large lumen so that they look like ducts. Some
of them may be in form of solid cords of cells.
 Extensive branching of duct system seen.
Plate 73 : ACTIVE MAMMARY GLAND
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
 In lactating mammary gland the glandular elements
proliferate so that they become relatively more
prominent than the connective tissue.
 The interlobular connective tissue septum is very thin.
 The lobules are formed by compactly arranged alveoli.
 The alveoli are lined by simple cuboidal secretory
epithelium and associated myoepithelial cells. Their
lumen contains eosinophillic secretory material which
appear vacuolated due to the presence of fat droplets.
Plate 74 : PITUITARY GLAND
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
 The pars anterior of the hypophysis cerebri consists of
cells separated by fenestrated sinusoids.
 The cells are of three types
 The pink staining cells are alpha cells or acidophils.
 The cells with bluish cytoplasm are beta cells or
basophils.
 Cells in which the cytoplasm is not conspicuous,
and the nuclei are closely packed, are
chromophobe cells.
 The pars intermedia is poorly developed in the human
hypophysis.
 In ordinary preparations the most conspicuous feature
is the presence of colloid filled vesicles. These vesicles
are remnants of the pouch of Rathke.
 The pars posterior consists of numerous unmyelinated
nerve fibres which are the axons of neurons located in
the hypothalamus.
 Situated between these axons there are supporting
cells of a special type called pituitocytes.
 The collection of secretory granules at the terminal
portion of axonal processing is called as Herring
bodies.
Plate 75 : THYROID GLAND
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
 The thyroid gland is made up of follicles lined by
cuboidal epithelium.
 In photomicrograph in low magnification it can be
seen that follicles vary in shape and size.
 Each follicle is filled with a homogenous pink colloid
proteinaceous material composed primarily of
thyroglobulin that has been produced by the follicular
epithelial cells.
 Parafollicular cells are present in relation to the
follicles and also as groups in the connective tissue.
 Note the blood vessels between follicles.
Plate 76 : PARATHYROID GLAND
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
 The cells of parathyroid glands are of two main types
 Chief cells or principal cells.
 Oxyphil cells or eosinophil cells.
 The chief cells are much more numerous than the
oxyphil cells.
 The chief cells are seen to be small round cells with
vesicular nuclei. Their cytoplasm is clear and either
mildly eosinophil or basophil.
 The oxyphil cells are much larger than the chief cells
and contain granules that stain strongly with acid dyes.
Their nuclei are smaller and stain more intensely than
those of chief cells.
 Adipose cells are also seen.
Plate 77 : SUPRARENAL GLAND
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1) In zona glomerulosa, the cells are arranged as inverted Ushaped formations. The cells of the zona glomerulosa are
seen to be small, polyhedral or columnar, with basophilic
cytoplasm and deeply staining nuclei.
2) In zona fasciculata, the cells are arranged in straight
columns, two cell thick. Sinusoids intervene between the
columns. The cells of the zona fasciculata are seen to be
large, polyhedral, with basophilic cytoplasm and vesicular
nuclei.
3) The cells in zona reticularis are smaller and more
acidophilic than other two layer. The zon reticularis is
made up of cords of cells that branch and form a
network.
4) The medulla of the suprarenal gland is made up of
chromaffin cells. The chromaffin cells are arranged in
groups or columns which are separated by wide
sinusoids.
Plate 78 : CEREBRUM
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1) A slide of cerebral cortex shows outer grey and inner
white matter. Multipolar neurons of various shapes are
arranged in six layers in the grey matter.
2) From the superficial surface downwards these laminae
are :
 Plexiform or molecular layer
 External granular layer
 Pyramidal cell layer
 Internal granular layer
 Ganglionic layer
 Multiform layer
3) The plexiform layer is made up predominantly of fibres
although a few cells are present.
4) The external and internal granular layers are made up
predominantly of stellate cells.
5) The predominant neurons in the pyramidal layer and
ganglionic layer are pyramidal.
6) The largest pyramidal cells are found in the ganglionic
layer.
7) The multiform layer contains cells of various sizes and
shapes.
Plate 79 : CEREBELLUM
DRAWING :
IDEAL SLIDE :
IDENTIFICTION POINTS :
1) The section of cerebellum shows leaf-like folia.
2) The cortex is covered by piamater which appears as a
thin layer of collagen fibres. Blood vessels may be seen
just beneath the piamater.
3) Outer grey mater is arranged in three layers from
without inwards :
 Molecular layer- very few nuclei of neurons seen.
Many cell processes present. Appearance of the
layer is pale.
 Purkinje cell layer- single layer of big flask shaped
pink neurons
 Granular cell layer- appears very dark blue
because of presence of abundant nuclei of
neurons.
4) Inner white matter shows axons which appear as pink
fibres.
5) Nuclei of neuroglia are present both in grey and white
matter.
Plate 80 : SPINAL CORD
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1) The spinal cord has a characteristic oval shape. It is
made up of white matter which containing mainly of
myelinated fibres; and grey matter which containing
neurons and unmyelinated fibres.
2) The grey matter lies towards the centre and is
surrounded all round by white matter.
3) The grey matter consists of a centrally placed mass and
projections(horns) that pass forwards and backwards.
4) The grey matter of the right and left halves of the
spinal cord is connected across the middle line by the
grey commissure that is traversed by the central canal.
5) The cental canal of the spinal cord contains
cerebrospinal fliud. The canal is lined by ependyma.
Plate 81 : SENSORY GANGLIA
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1) In H & E stained sections the neurons of sensory
ganglia are seen to be large and arranged in groups
chiefly at the periphery of the ganglion.
2) The neurons of sensory ganglia can be seen to be
unipolar.
3) The groups of cells are separated by groups of
myelinated nerve fibres.
4) The cell body of each neuron is surrounded by a layer
of flattened capsular cells or satellite cells.
5) Outside the satellite cells there is a layer of delicate
connective tissue.
Plate 82 : AUTONOMIC GANGLIA
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1) The neurons of autonomic ganglia are smaller than
those in sensory ganglia, they are seen to be
multipolar.
2) The neurons are not arranged in definite groups as in
sensory ganglia, but are scattered throughout the
ganglion.
3) The nerve fibres are non-myelinated and thinner.
4) Satellite cells are present around neurons of autonomic
ganglia, but they are not so well defined.
Plate 83 : CORNEA
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1) The cornea is made up of five layers :
 The outer most layer is of non-keratinised
stratified squamous epithelium .
 The corneal epithelium rests on the structureless
anterior limiting lamina [also called Bowman`s
membrane]
 Most of the thickness of the cornea is formed by
the substantia propria made up of collagen fibres
embedded in a ground substance.
 Deep to the substantia propria there is a thin
homogenous layer called the posterior limiting
lamina.
 The posterior surface of the cornea is lined by a
single layer of flattened or cuboidal cells.
2) The structure of the cornea is fairly distinctive and its
recognition should not be a problem.
Plate 84 : EYELID
DRAWING :
IDENTIFICATION POINTS :
1) Anteriorly, there is a layer of true thin skin.
2) Considerable thickness of the lid is formed by fasciculi
of the palpebral part of the orbicularis oculi muscle.
3) The ‘skeleton’ of each eyelid is formed by a mass of
fibrous tissue called the tarsus, or tarsal plate.
4) On the deep surface of the tarsal plate, there are a
series of vertical grooves in which tarsal glands or
meibomian glands are lodged.
5) Modified sweat glands, called cillary glands or glands
of Moll are present in the lid near its free edge.
6) Sebaceous glands present in relation to eyelashes
consistitute the glands of Zeis. They open into hair
follicles.
7) The inner surface of the eyelid is lined by the palpebral
conjunctiva.
Plate 85 : PINNA
DRAWING :
IDENTIFICATION POINTS :
1) The auricle [pinna] consists of a thin plate of elastic
cartilage covered on both sides by true skin.
2) Epithelium is stratified squamous keratinising, hair
follicles, sebaceous glands, and sweat glands are
present in the skin, adipose tissue is present only in
lobule.
Plate 86 : EYEBALL & RETINA
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1) The wall of the eye ball is made up of several layers as
follows :
 Sclera, made up of collagen fibres.
 Choroid, containing blood vessels and pigment
cells. The remaining layers are subdivisions of the
retina.
 Pigment cell layer
 Layer of rods and cones
 Outer nuclear layer
 Outer plexiform layer
 Inner nuclear layer
 Inner plexiform layer
 Layer of ganglion cells
 Layer of optic nerve fibres.
2) The appearance is not likely to be confused with any
other tissue.
Plate 87 : COCHLEA & ORGAN OF CORTI
DRAWING :
IDEAL SLIDE :
IDENTIFICATION POINTS :
1) The cochlea is embedded in the petrous temporal
bone. It is in the form of a spiral canal.
2) The cone-shaped mass of bone surrounded by these
turns of the cochlea is called the modiolus which
contains a canal through which fibres of the cochlear
nerve pass.
3) A mass of neurons belonging to the spiral ganglion lies
to the inner side of each turn of the cochlea.
4) The parts to be identified in each turn of the cochlea
are the scala vestibule, scala media, the scala tympani,
the vestibular membrane, the basilar membrane, the
membrane tectoria, the organ of corti and the spiral
lamina.
5) Outer wall of the cochlear turn is the spiral ligament
and it is lined by avascularised epithelium (stria
vascularis).
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