13 Differences between Osteoblast and Osteoclast (With Table)

Osteoblast and osteoclast are crucial types of bone cells that consist of bone tissues or osseous tissues. These types of bone cells play an essential role during metabolic activities.

The coordination of action between these two bone cells helps in the formation and breakdown of bones. According to science, bone remodeling is the coordination action of osteoblast and osteoclast.

So, what is the main difference between osteoblast and osteoclast? The former is responsible for the formation of bones and the latter for the breakdown of bones. 

The bone remodeling process helps to enhance bone maintenance and regulation of vital minerals. Calcium and phosphorus are among the most important minerals for the bones. 

This article provides a comprehensive explanation of the differences between osteoblast and osteoclast.  Take the time to read through it and also get to know their similarities. 

Comparison Table (Osteoblast vs Osteoclast)

Basic Terms




Bone cells responsible for bone formation.

Bone cells responsible for the breakdown of bones.

Cell Size

Comparatively smaller.

Comparatively larger.

Cell Type



Cell Organelles

Relatively lesser number.

Relatively larger number.


Make protein-osteoid.

Do not make protein osteoid.

Cells Appearance

Cells do not possess sealing zones and ruffled borders.

Cells possess sealing zones and ruffled borders.

Hormones Produced


No hormone produced.

Parathyroid Hormone Receptors



Cell Production

Produce a large amount of alkaline phosphatase enzyme.

Produce a large amount of tartrate-resistant acid phosphatase enzyme.

Derived from

Pluripotent mesenchymal stem cells.

Hematopoietic cells of the granulocyte

Phagocytic-like Mechanism



End Result

Osteoblasts become osteocytes at the end of the bone formation.

Osteoclasts do not become osteocytes.


Formation and mineralization of bones

Bone breakdown and bone resorption

What is Osteoblast?

The osteoblast is a single nuclei cell that operates in the group during the formation and mineralization of bones. The bone cell plays a vital role during initial bone formation and remodeling.

The cells occur in a closely packed group on the surface of the bones. The bone cells are developed from osteogenic cells in the outer surface of the bone known as the periosteum.

The bone cell produces many cell products that enhance bone formation. Some of these cell products are growth factors, collagen, hormones, and enzymes.

The bone formation process results in osteoblast being surrounded by a growth matrix where the cells get trapped in Lacuna.

The trapped osteoblast cells become mature to form osteocytes which form a medium of communication between the bone surface and canaliculi which is a receiver of nutrients.

What is Osteoclast?

The osteoclast is bone cells that release acid and collagenase enzymes to break down mineral deposits on the osteoblast.

These cells are usually found on the surface of the bones and the broken down materials are later absorbed into the bloodstream.

The enzymes secreted by osteoclast cause the formation of small depression on the bone known as Howship lacunae. This is the part where the osteoclast tends to occupy.

These bone cells are normally derived from bone marrow and circulating cells such as monocytes and macrophages.

Osteoclasts are multinucleated cells that comprise about 200 nuclei per cell. The bone cells have microvilli which occur on the surface to form the brush-like structure for bone resorption.

The bone cell secretes acid phosphatases which are responsible for dissolving calcium, collagen, and phosphorus in osteoclast.

Later, the products of the demineralization of bones such as phosphorus and calcium are released into the bloodstream. The good news is that osteoclast does not work on the osteoid.

Main Differences Between Osteoblast and Osteoclast

  1. The osteoblast entails the formation and mineralization of bones while the osteoclast involves bone breakdown and resorption.
  2. Osteoblasts are single cells that operate in groups while osteoclasts are multinucleated cells that comprise about 200 nuclei per cell.
  3. Osteoblasts are formed from the osteogenic cells whereas osteoclasts are developed from bone marrow, macrophages, and monocytes.
  4. Osteoblasts are derived from the mesenchymal osteoprogenitor cells that promote the bone remodeling process while osteoclasts are derived from hematopoietic cells responsible for bone resorption.
  5. Osteoclast cells are comparatively larger when compared to osteoblast cells.
  6. Osteoclast cells have a larger amount of organelles such as mitochondria, vacuoles, and lysosomes as compared to osteoblast.
  7. Osteoblast cells tend to make protein osteoid while osteoclast cells do make any proteins.
  8. Osteoblast cells contain a large amount of alkaline and phosphatase enzyme while osteoclast contains acid, tartrate-resistant, and phosphatase enzyme.
  9. Osteoclast cells are equipped with the phagocytic-like mechanism while osteoblast cells are not equipped.
  10. The end result of osteoblast cell is osteocytes while osteoclast does not have any end result.

 Similarities Between Osteoblast and Osteoclast

  1. Both are bone cells
  2. Both get involved in the bone remodeling process
  3. Both promote bone repair
  4. Both the cells have a nucleus
  5. Both are connective tissues
  6. Both are found in the bone
  7. Both are metabolically active cells

Frequently Asked Question

  • How Do Osteoblasts Differ from Osteoclasts?

Osteoblasts are large cells that dissolve in the bone and they are mainly found on the surface of the bone next to the dissolving one. Osteoclasts are bones that form new bones. They are found in the bone marrow and are related to structural cells. 

  • What Type of Cells Divides and Differentiate into Osteoblast or Osteoclast?

Osteogenic cells. They are bone cells that divide and differentiate to form new bones. They secrete a collagen matrix and calcium salts. 

  • What Stimulates Osteoblast Activity?

Parathyroid hormone. It is a protein made by the parathyroid gland under the control of serum calcium activity.

  • What are the Two Types of Bone Cells?

The main types of bone cells are osteoblastsosteoclastsosteocytes, and osteoprogenitors. They are unique in function and they are found in different parts of the body. 

  • What Activates Osteoblasts?

Primary murine osteoblasts and the osteoblast cell line MC3T3 will be activated with osteotropic agents (LPS, PTH, IL-1, etc.) or antibodies to specific cell surface determinants.

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Both osteoblast and osteoclast are two types of bone cells involved in the remodeling and repair of the bones. Besides that, they are both found in the bone.

The way they are derived and their roles are what make the two bone cells quite different. Use the above differences for better insight into their distinction.

I hope the article has been useful. Use the comment section to share your views and more insight into the differences between osteoblast and osteoclast.

More Sources and References

  1. Cell Types in Bones. Biology LibreText

  2. Osteoblast. Wikipedia 

  3. Osteocyte. Britannica 

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