histology of muscular, and skeletal tissues

1. Histology of muscle, cartilage
and bone
By
Dr. Abdul Waheed Ansari
Prof. &Chairperson Anatomy, RAKCODS.
RAKMHSU.
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2. Learning outcomes for this lab
The students are able to :
• Differentiate the between the skeletal, smooth
and cardiac muscles histologically.
• Classify the bone cells found in the bone tissue.
• Identify the microscopic features of hyaline
cartilage and sites where they occur in the body
• Compare, contrast microscopic features of elastic
cartilage and fibrocartilage. Mention the sites
where they are located.
• Compare and contrast the various bone cells and
their functions.
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3. The characteristic features of muscular
tissues
• They are made up of many cells that are close
together & there is little extracellular material
between muscle cells.
• The muscular tissue are well vascularized.
• The cells are elongated.
• The cells contain myofilaments (contractile
proteins).
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4. Three kinds of muscle tissues
• Skeletal muscle
• Cardiac muscle
• Smooth muscle
• Skeletal muscle cells are very long (up to
30 cm), cylindrical, striated and
multinucleated.
• The striations reflect the regular pattern
of distribution of the myofilaments inside
the cells.
• The nuclei are located on the periphery
of the cells.
• Skeletal muscle cells are arranged in
parallel, in bundles tied together by
connective tissue and anchored at both
ends by tendons to bones or other
supporting tissues.
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5. Cardiac muscle cells are shorter than the
skeletal muscle cells.
• Cardiac muscle cells are
elongated, branched and
striated.
• The striations reflect the
regular pattern of distribution
of the myofilaments inside the
cells.
• Cardiac muscle cells have one
nucleus, sometimes two at the
center of the cell.
• Cardiac cells fit together tightly
at dark-staining junctions called
intercalated discs.
• Intercalated discs are found
only in cardiac muscle tissue.
• Cardiac muscle cells are found
in9/ 2t4h/20e14 heart only. 5

6. Smooth muscle cells
• Are spindle-shaped, have
one nucleus and are not
striated.
• The nucleus is central in
position and oval in
shape.
• Smooth muscles are
found in the walls of
hollow organs, digestive
and urinary tract organs,
blood vessels, uterus.
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7. Hyaline cartilage
• The chondrocytes lie
within chambers in the
matrix called lacunae.
• The hyaline cartilage
contains a gel-like
amorphous matrix.
• Fine collagen fibers are
present in the matrix, but
they are not visible with
ordinary staining
technique.
• It is found at the ends of
long bones .
• It supports the tip of the
nose, the trachea and the
bronchi.
• It forms most of the larynx
and connects the ribs to the
sternum.
• It is also found in epiphyseal
plates of children.
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8. Fibrocartilage
• Fibrocartilage is quite
similar to hyaline cartilage
but its matrix contains
many coarse collagen
fibers running parallel to
each other.
• It is found in pubic
symphysis , intervertebral
discs and the menisci of
knees.
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9. Elastic cartilage
• Elastic cartilage is quite
similar to hyaline cartilage
but its matrix contains
many elastic fibers.
• It is found in the epiglottis
of the larynx, the external
ear and the (Eustachian)
auditory tubes.
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10. Bone histology
• Bone tissue is highly vascular
where as cartilage tissue is
avascular.
• An osteoblast is an immature
bone cell.The osteoblast is
the bone forming cell.
• A bone lining cell is a resting
osteoblast.
• osteoprogenitor cells are
derived from mesenchymal
cells and have the ability to
differentiaite into
osteoblasts.
• The mature bone cell is called
an osteocyte.
• An osteocyte rests in a space
called a lacuna.
• An osteoclast is a
multinucleated cell involved in
the degradation of bone.
• It is a bone resorbing cell.
• Howship's lacuna is a space
seen underneath an osteoclast.
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11. • A = osteoblasts,
• B = osteocytes,
• C = osteoid,
• D = cement line
• E = bone
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12. Histology of Compact Bone
• Compact bone is also
called dense bone.
• Compact bone is
composed of closely
packed osteons.
• An osteon is also called
a Haversian system.
• An osteon is the
cylindrical structure with
bone.
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13. Osteoclasts are the bone removing cells
• They work by sealing off an
area of bone surface, when
activated, they pump out
hydrogen ions to produce a
very acid environment,
which dissolves the
hydroxyapatite.
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14. References
• http://www.zoology.ubc
.ca/~biomania/tutorial/
tuthisto/smmry01.htm
• http://swc2.hccs.edu/bi
ol/labs/ap1/tissues/elas
ticCart.htm
• http://www.histology-world.
com/factsheets/b
one1.htm
• https://casweb.ou.edu/
pbell/histology/Caption
s/Cartilage/11.fibro.htm
l
• http://resources.school
science.co.uk/mrc/oste
opor/page3.html
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