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Associated tissues

Bones

  • Provide the framework and internal core structure for the attachment of muscles
  • Bone is a living rigid tissue which forms the support structures for the rest of the body. The process of bone formation is called ossification.
  • The matrix of bone contains a dense arrangement of collagen fibres together with mineral salts of calcium, magnesium and phosphates.
  • The calcium salts give bone its hardness and rigidity while collagen fibres give bones its flexibility and strength.

Functions of bone

  • To serve as a firm support framework for the whole body.
  • To protect such delicate structures as the brain and spinal cord
  • To serve as levers, working with attached muscles to produce movement.
  • To serve as a storehouse for calcium salts , which may be reabsorbed into the blood if there is not enough calcium in the diet,
  • To produce blood cells in the red marrow.

Microscopic structure of a long bone

  • Numerous hollow tunnels called Haversian canals occur within the matrix of bone tissue and run parallel with the length of the bone. Under the microscope they appear as black circles against a lighterbackground.
  • Each Haversian canal is surrounded by concentric rings of compact bone called lamellae
  • Each of these layers contains a ring of fluid-filled cavities called lacunae. Each of these lacuna will contain a number of bone cells called osteocytes.
  • The lacunae are linked to each other and to the Haversian canal by a system of very tiny interconnecting canals called canaliculi. Strands of cytoplasm extend through these canals which supply the osteocytes with oxygen and nutrients and remove waste products
  • The Haversian canals, lacunae, osteocytes and canaliculi together form a unit called a Haversion System and a number of these systems make up compact bone.
  • Apart from osteocytes which are embedded in the lacunae of bone there are two other types of bone cells

Osteoblasts : Bone forming cells. These cells allow the bone to change and remodel its shape as the organism grows and responds to stresses. If a bone is broken or if strengthening is needed, bone cells lay down new tissue and repair damaged tissue

Osteoclasts: Special bone cells for destroying and reabsorbing bone tissue.

Cartilage

Main features

  • cartilage is a tough semi-transparent flexible tissue
  • it is enclosed by a fibrous capsule called the perichondrium
  • consists of living cells called chondrocytes which secrete a rubbery protein matrix called chondrin
  • chondrocytes occur in small fluid-filled spaces called lacunae which are scattered throughout the matrix.
  • There are no blood vessels or nerves in the matrix.

Cartilage and bone

Infant and young children do not have bones like those of adults. Their bones are made mostly of cartilage, a firm elastic fibrous material.

As the individual grows and matures, the cartilage is gradually replaced by bone cells which deposit crystals of calcium carbonate and calcium phosphate.

This process called ossification greatly increases the strength of the bone.

Bones usually continue to grow through adolescence. During this time a layer of cartilage still exists between the head and shaft at either end of thebone. The growth of the bone does not interfere with the way joints fit together.Eventually once all the cartilage has become ossified bone growth will stop

Types of cartilage

Hyaline Cartilage:

Appearance: glass-like, bluish-white in colour, few fibres present

Location:

  • at the ends of bones as articular cartilage
  • where the ribs are joined to the sternum
  • forms rings in the trachea
  • larynx and tip of nose
  • as temporary cartilage in bones.

Functions:

  • reduces friction at the joints.
  • allows a degree of movement during breathing
  • keeps the trachea open.
  • Forms permanent structures
  • Allows for bones to increase in length.

Fibrocartilage

Appearance: has numerous white collagen fibres in the matrix.

Location:

  • as cartilaginous discs between the vertabrae
  • in the rim of sockets of ball and socket joints
  • between the pubic bones

Functions:

  • act as shock absorbers
  • make the cavity deeper without hampering movement
  • allows for limited movement

Elastic cartilage

Appearance: has a network of yellow elastic fibres in the matrix.

Location:

  • in the pinna of the ear
  • in the epiglottis

Functions:

  • maintains the shape of the ear but also allows for changes in shape.
  • strengthens the epiglottis which prevents food from entering the trachea.

Ligaments

  • Ligaments consist of white collagen fibres and a network of yellow elastic fibres.
  • The collagen fibres are less orderly and more randomly arranged than in tendons and ligaments have varying amounts of elastic fibres.
  • Ligaments join bone to bone and they also control the degree of movement allowed between the two bones. This is achieved by the amount of elasticity in aligament i.e. a ligament will only stretch enough to allow a particular movement to happen.
  • The more elastic fibres in the ligament the greater the articulation between two bones. Thus the attachment of ligaments between bones keep the bones of a jointin position.
  • By restricting bone movement ligaments will prevent any dislocation during normal actions.

Tendons

Attach muscles to bones and facilitate the various positions of the body related to movement and balance.

  • Tendons consist of non elastic collagen fibres only.
  • These are densely packed, arranged in parallel bundles and are extremely strong, less flexible and more resistant to stress
  • The fibres give tendons a white shiny appearance.
  • There is a minimal amount of matrix present.

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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why and for what was five kingdom of classification of organisms introduced
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SUBHIKSHA
Comment on the ozone depletion over the period of 1982 to 1996
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Source:  OpenStax, Siyavula: life sciences grade 10. OpenStax CNX. Apr 11, 2012 Download for free at http://cnx.org/content/col11410/1.3
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