USMLE Forums banner

1 - 3 of 3 Posts

·
Registered
Joined
·
76 Posts
Discussion Starter #1
Hey guys

is Type 1 collagen secretion mediated by osteoblasts or chondroblasts or chondrocytes?

In FA it states that "cartilaginous model of bone is first made by chondrocytes"

so confused, also a quick explanation and how to differentiate the three of these?

thanks in advance:eek::eek::eek::eek::eek::eek::eek::eek:
 

·
Registered
Joined
·
19 Posts
Osteoblasts (Bone cell) are specialized to to synthersize and secrete the components of osteoid, typeI collagen, and GAGs.
chondroblast and chondrocyte are differentiated from chondroid progenitor cells derived from mesenchyme, and they form hayaline cartilaginous template in endochondral bone formation.
 

·
Registered
Joined
·
133 Posts
There are two types of ossification. En-chondral and inter-membranous.
The type of ossification depends on the type of bone (location and shape).

Let me break it down for you.

1. Enchondrous - (has the word chondro; AKA cartilage)
• Long Bones
• Mesenchymal cells differentiate into CHONDROBLASTS > lay down cartilage. Think of this cartilage as a MATRIX TEMPLATE.
• this matrix gets INVADED later on by CLASTS AND BLASTS. >>>> calcified later to become COMPACT BONE

THIS ENCHONDROUS calcification IS SCREWES with PAGETS. (Aka woven bone)

2. Inter-Membranous
• flat bones (eg skull)
• the mama Mesenchymal cells DIRECTLY diff into BLASTS >>>> secrete OSTEOID MATRIX.

So now you know, why cartilage is present in the ENCHONDROUS calcification (name implies that there are CHONDROBLASTS).

As for type 1 collagen, a variety of cells can secrete collagen

1. Fibroblasts
2. CHONDROBLASTS (cartilage has type 1 collagen)
3. Osteoblasts (type 1 collagen in bone!!)
4. myo fibroblasts in a scar!

This is all I can recall for now Happy-2

Hey guys

is Type 1 collagen secretion mediated by osteoblasts or chondroblasts or chondrocytes?

In FA it states that "cartilaginous model of bone is first made by chondrocytes"

so confused, also a quick explanation and how to differentiate the three of these?

thanks in advance:eek::eek::eek::eek::eek::eek::eek::eek:
 
1 - 3 of 3 Posts
Top