Question

Immature bone cells are called as
A. Osteoclasts
B. Osteocytes
C. Osteo Cells
D. Osteoblasts

Answer 1

Hint:-Bone consists of four types of cells, and each cell has its unique function which is found
in different locations of bones, and mainly bone related cells are progenitor cells of bone, from which
osteoblast and other cells are formed by differentiation, and all of them together and responsible for
growing, shaping and maintenance of bones.

Complete step-by-step solution:-
1. Bone consists of 4 different types of cells which include osteogenic progenitor cells, and
osteoblast, Osteocytes and osteoclast.
2. Osteogenic progenitor cells are undifferentiated cells which have high mitotic activity, and they
are only bone cells which divide and they are the immature osteogenic cells found in deep layers
of periosteum and bone marrow cells.
3. So the precursor cells undergo differentiation and form the osteoblast cells, this are the bone
cells which are responsible for forming the new bone and they are found in the growing portion
of the bone, which include periosteum and endosteum.
4. This osteoblast cells which formed from precursor cells do not divide, instead they synthesize
and secrete the collagen matrix and calcium salts, as the secreted matrix surrounding the
Osteoblast calcifies where this osteoblast gets trapped within it.
5. Because of all this secretions, there is change in the structure of osteoblast, and it is formed to
osteocyte, which is the primary mature bone cell.
6. Osteocytes are located in the space surrounded by bone tissue, and they maintain the mineral
concentration of the matrix through secretion and enzyme.
7. So both osteoblast and osteocytes lack the mitotic activity. And these both are able to
communicate with each other, and they receive nutrients through long cytoplasmic process
which extend through canaliculi.
8. There are 3 rd category of cells which are differentiated from the osteogenic cells that are
osteoclast, and this are the cells which are responsible for resorption.
9. Osteogenic cells- precursor bone cells
Osteoblasts—immature bone cells
Osteocytes—mature bone cells
Osteoclasts resorptive bone cells.
So, the correct option is D.

Note:- Osteogenic cells are stem cells which differentiate to form osteoblast, and this cells do not divide where they secrete calcium salts and collagen matrix and get trapped to form mature bone cells called osteocytes, both osteoblast and osteocytes do not divide, and other cells are osteoclast, responsible for resorption all together maintain the activity of bone.