chapter 15 ;The musculoskeletal system: support and movement Flashcards
(85 cards)
What are the four types of cells found within bone tissue?
Osteogenic cells, osteoblasts, osteocytes, and osteoclasts.
What is the function of osteogenic cells?
- high mitotic activity;
- they differentiate and develop into osteoblasts.
- located: DEEP layers of the periosteum and endosteum
What role do osteoblasts play in bone tissue?
Osteoblasts are responsible for forming new bone; they synthesize and secrete the collagen matrix and calcium salts.
Where are osteoblasts found in bone tissue?
Osteoblasts are found in the growing portions of bone, such as the periosteum and endosteum.
Do osteoblasts divide?
No, osteoblasts do not divide.
What are osteocytes, and where are they located?
Osteocytes are the primary cell of mature bone, located in a space called a lacuna.
What is the main function of osteocytes?
Osteocytes maintain the mineral concentration of the bone matrix.
How do osteocytes communicate and receive nutrients?
They use long cytoplasmic processes to communicate with each other and receive nutrients.
Do osteocytes have mitotic activity?
No, like osteoblasts, osteocytes lack mitotic activity.
What is the function of osteoclasts?
Osteoclasts are responsible for bone resorption (breakdown).
Where are osteoclasts found in bone tissue?
Osteoclasts are found on bone surfaces.
What is unique about the origin of osteoclasts?
Osteoclasts are multinucleated and originate from monocytes and macrophages (types of white blood cells), not from osteogenic cells.
What is the microscopic structural unit of compact bone called?
An osteon, or Haversian system.
What is each osteon composed of?
oncentric rings of calcified matrix called lamellae (singular = lamella).
What runs down the center of each osteon?
The central canal, or Haversian canal.
What does the central (Haversian) canal contain?
Blood vessels, nerves, and lymphatic vessels.
What are the canals called that branch off at right angles to the central canal?
Perforating canals, also known as Volkmann’s canals.
Where are osteocytes located in compact bone?
Inside spaces called lacunae (singular = lacuna).
What is the nature of spongy bone?
Light, soft, and spongy.
What structural units make up spongy bone?
Trabeculae.
What function does the bone marrow in spongy bone have?
Produces red blood cells (RBCs) and white blood cells (WBCs).
What is the nature of compact bone?
Heavy, tough, and compact.
What structural units make up compact bone?
Osteons.
What function does the bone marrow in compact bone have?
Stores fat.