Types of bone, Biology

TYPES OF BONE -

On the basis of its texture, a bone is of two types -

  1. Spongy or cancellous or tubercular bone and
  2. Compact or periosteal or dense bone.

213_difference between bones.png

2330_difference between bone and cartilage.png

Ossification (Bone formation)

The skeleton is formed entirely of cartilage in an early embryo.

The process of bone formation is called ossification or osteogenesis.

Bones are of the following types according to their source of formation -

1.      Cartilaginous or Replacing Bones -

  1. These bones develop from the pre-existing cartilage and practically replace the cartilage.
  2. They are also called endochondrial bones. Examples: humerus, femur.

2.      Investing or Dermal or Membrane Bones -

  1. These bones develop in the dermis of the skin as thin plates and sink to get attached over the original cartilaginous endoskeleton.
  2. In fact these bones become invested upon original cartilages hence their name.
  3. Examples: frontal, nasals, vomers and parietals of the skull.

3.      Sesamoid Bones -

  • These bones are formed in the tendons at the joints. Example: patella (knee-cap).

4.      Visceral Bones -

  1. These are formed in the soft organs (= viscera).
  2. Examples:

os cordis in the heart of some ruminants (e.g., deer),

os penis in the penis of most bats, insectivores, rodents (e.g., rats), carnivores (e.g., dog,walrus), whales, some primates (not man),

os clitoris in the clitoris of many carnivores, and

os palpebrae in the eyelids of crocodiles.

  • A small bone also develops in the crest of a bird and snout of a hog.

OSTEOCLASTS -

  1. These cells are derived from osteoblasts and osteocytes, rich in acid phosphatase and contain slightly basophilic cytoplasm and are lysosome-rich, multinucleate cells which destroy bone matrix.
  2. They are also called bone destroying cells.

OSTEOMYELITIS -

  • Inflammation of the bone marrow and adjacent bone and epiphysial cartilage.

PAGET'S DISEASE-

  • Irregular thickening and softening of bones. A bone kept in KOH remains unaffected

OSTEOMYELODYSPLASIA

  1. Enlargement of the bone marrow cavities, thinning of the osseous tissue, thinning of osseous tissue, large thin- walled vascular spaces, leukopenia (fall in WBC count) and irregular fever.
  2. When required, calcium and phosphate are released from the bone into the blood under the influence of the hormones, parathormone from the parathyroid glands and calcitonin from the thyroid gland.
Posted Date: 10/1/2012 3:15:49 AM | Location : United States







Related Discussions:- Types of bone, Assignment Help, Ask Question on Types of bone, Get Answer, Expert's Help, Types of bone Discussions

Write discussion on Types of bone
Your posts are moderated
Related Questions
Explain the Filtration - Air Sampling? Filtration - Air stream may also be filtered through a micro-filter.  Microorganisms are released from the filter using a suitable diluen

PHYLUM  NEMATODA (= NEMATHELMINTHES ) Definition and Introduction                                                                             Bilateral  and protostomial

how much classification of protozoa

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Q. Can mitosis occur in haploid (n) cells and in triploid cells? The mitotic cell division can occur in haploid (n) cells, diploid (2n) cells, triploid (3n) cells, and so on. M

you are setting up a pcr reaction to amplify a 1000 basepair long dna grament. in your 50 microliter reaction volume you have 100 nanogrM OD RWMPLrw sn QIRH eoufly 50/50 at/gc 100

Rainfall is high, sometimes higher than tropical rain forests but seasonal. There are pronounced wet and dry periods, and so are winter and summer seasons. The soils are brown in c

Cellular Respiration: General Formula For aerobic respiration (in the presence of O 2 ) C 6 H 12 O 6 + 6O 2 --> 6H 2 O + 6CO 2 + 36ATP (theoretical)

I know the answer to the question but when I selected buy it said $80, now I want to know if it is $80 more or if you will subtract what I already paid to $80 and therefore will on

Ecological isolation is based on the fact that population shows preference to one habitat over the other. This extensive forests become barriers to the dispersal of organims living