The key difference between bone deposition and resorption is that bone deposition is the process of depositing new bone matrix by the osteoblasts while bone resorption is the process by which osteoclasts break down the tissue in bones and release minerals to the blood.
Bone is a calcified piece of hard, whitish, living and growing tissue that makes the skeleton in humans and other vertebrates. It consists of different cell types including osteoblasts, osteocytes, osteoclasts, and bone lining cells. Bones change over their life span in order to protect the structural integrity of the skeletal system and balance the calcium and phosphorus in the body. Thus, this process is called bone remodeling. Bone resorption and bone deposition are the two major events of bone remodeling. Resorption occurs in old or damaged bones while creating new bone materials. Two types of bone cells are responsible for bone resorption and deposition phases of bone remodeling. They are osteoclasts and osteoblasts.
CONTENTS
1. Overview and Key Difference
2. What is Bone Deposition
3. What is Bone Resorption
4. Similarities Between Bone Deposition and Resorption
5. Side by Side Comparison – Bone Deposition and Resorption in Tabular Form
6. Summary
What is Bone Deposition?
Bone deposition is one of the two main events of bone remodeling. It is the process of depositing new bone materials. Osteoblasts are the bone-forming cells that carry out bone deposition. They secrete an organic matrix that is rich in collagen protein.
Figure 01: Bone Deposition
Once hydroxyapatite is deposited on the secreted organic matrix, it becomes hardened bone. In other words, bone deposition can be defined as the deposition of hydroxyapatite on the bones.
What is Bone Resorption?
Bone resorption is the second major event of bone remodeling. It is the process that breaks down old bones as well as damaged bones. Therefore, this prevents the accumulation of damaged bones in the new bones.
Figure 02: Bone Resorption
During the bone resorption, the bone matrix dissolves. In simple words, hydroxyapatites of the bones dissolve while releasing the minerals into the blood during bone resorption. Osteoclasts are the cells that are responsible for bone resorption.
What are the Similarities Between Bone Deposition and Resorption?
- Bone deposition and bone resorption are two major processes of bone remodeling.
- However, bone deposition involves the deposition of hydroxyapatites while bone resorption involves dissolving of hydroxyapatites.
- Importantly, the rate of bone deposition and rate of bone resorption are equal in a healthy individual.
- Both processes are important in order to maintain ion homeostasis in our body.
What is the Difference Between Bone Deposition and Resorption?
Bone deposition is the process of forming new bone materials while bone resorption is the process of breaking old or damaged bones. So, this is the key difference between bone deposition and resorption. Moreover, further difference between bone deposition and resorption is that the osteoblasts are responsible for bone deposition while osteoclasts are responsible for bone resorption.
Furthermore, osteoblasts have a mesenchymal origin while osteoclasts have a hematopoietic lineage. During bone deposition, osteoblasts deposit new collagen and minerals. However, during bone resorption, lysosomal enzymes and hydrogen ions of the osteoclasts break down the bone matrix. Therefore, this is also a significant difference between bone deposition and resorption.
Summary – Bone Deposition vs Resorption
In brief, bone remodeling is an essential process in order to prevent the accumulation of damaged bones and maintaining mineral homeostasis. It occurs via two major processes as bone deposition and resorption. Bone deposition refers to the process of deposition of new bone materials while bone resorption refers to the breakdown down of old or damaged bones. Osteoblasts are the cells that are responsible for bone deposition while osteoclasts are the cells that are responsible for bone resorption. Thus, this is the summary of the difference between bone deposition and resorption.
Reference:
1. Rowe, Paul. “Physiology, Bone Remodeling.” StatPearls [Internet]., U.S. National Library of Medicine, 9 Mar. 2019, Available here.
2. “Bone Resorption.” Wikipedia, Wikimedia Foundation, 13 Feb. 2019, Available here.
Image Courtesy:
1. “Osteoclast” By Robert M. Hunt at English Wikipedia – Transferred from en.wikipedia to Commons by Kauczuk using CommonsHelper. (Public Domain) via Commons Wikimedia
2. “Osteoblast Organization” By Physio Muse – (CC BY-SA 3.0) via Commons Wikimedia