Bone Physiology Flashcards
(41 cards)
What are the primary functions of bones?
- Muscle attachment
- Protection and support of soft materials
- Blood cell production
- Storage of minerals and some triglycerides
These functions highlight the essential roles bones play in the human body.
What is ossification?
The process of bone formation
Ossification is also known as osteogenesis.
In what situations do bones form?
- During embryological and fetal development
- When bones grow before adulthood
- When bones remodel
- When fractures heal
Each situation outlines a different aspect of bone development and maintenance.
What are the two forms of ossification?
- Intramembranous bones
- Endochondral bones
These forms describe how bones develop from connective tissue or cartilage.
What type of bones form as intramembranous bones?
The broad, flat bones of the skull
Intramembranous ossification involves the direct formation of bone from connective tissue.
What are osteoblasts?
Cells that deposit a bony matrix around themselves
When completely surrounded by the matrix, osteoblasts become osteocytes.
What is the periosteum?
Connective tissue that surrounds the diaphysis of bones
It nourishes, protects, and provides attachment for tendons and ligaments.
What is the role of osteoprogenitor cells in intramembranous bone formation?
They cluster in ossification centers and become osteoblasts
This process initiates the formation of bone tissue.
What is compact bone known for?
Providing protection and support
Compact bone is dense and forms the outer layer of bones.
What is spongy bone’s characteristic?
Lightweight and provides tissue support
Spongy bone contains trabeculae and is found at the ends of long bones.
Where are osteocytes located?
Within lacunae that lie in concentric circles around central canals
This arrangement is crucial for nutrient and gas exchange.
What connects central canals in compact bone?
Transverse perforating (Volkmann’s) canals
These canals allow nerves and vessels to connect through the bone.
What is the medullary cavity?
The hollow space within the diaphysis of long bones
It stores yellow bone marrow and reduces the weight of the bone.
What occurs during the reactive phase of fracture healing?
An early inflammatory phase where blood vessels break and a fracture hematoma forms
This phase lasts several weeks.
What vitamins are important for bone growth?
- Vitamin D
- Vitamin C
- Vitamin A
- Vitamin K
- Vitamin B12
Each vitamin plays a specific role in bone health and function.
What is a greenstick fracture?
A partial fracture where one side of the bone is broken and the other side bends
This type of fracture typically occurs in children.
What is appositional growth in bones?
The thickening of bones through the action of osteoblasts and osteoclasts
This process allows bones to increase in diameter.
What role does parathyroid hormone (PTH) play in bone health?
Stimulates osteoclasts to increase bone resorption and release calcium into the bloodstream
PTH is crucial for maintaining calcium levels in the body.
What type of marrow occupies the spongy bone?
Red marrow
Red marrow is responsible for the formation of blood cells.
What is the role of calcitonin in bone metabolism?
Inhibits osteoclasts and accelerates calcium deposits in bone
Calcitonin helps lower blood calcium levels.
What happens to bone mass in post-menopausal women?
They experience a decrease in bone mass as resorption outpaces deposition
This can lead to osteoporosis.
What is the primary function of yellow marrow?
Stores fat and occupies most cavities of bone in adults
Yellow marrow is important for energy storage.
What type of fracture is a Pott fracture?
Fracture of the distal end of the fibula with serious injury to the distal tibial articulation
This type of fracture commonly affects the ankle.
What is the role of osteoclasts in bone remodeling?
Tear down bone tissue
They are essential for bone resorption.
