Skeletal System 1 - Structure and Function Flashcards
What is the function of bone?
Support, Protection, Assists movement, Mineral homeostasis, Blood cell protection, Triglyceride storage
What is the function of bone with regards to support?
Structural framework for soft tissue | Attachment points for tendons & muscle
What is the function of bone with regards to protection?
Protects internal organs
What is the function of bone with regards to assisting movement?
Muscle attach to bone & produce movement
What is the function of bone with regards to Mineral homeostasis?
Calcium & phosphorus | Storage & release
What is the function of bone with regards to blood cell production?
Produce red blood cells | White blood cells | Platelets
What is the function of bone with regards to Triglyceride storage?
Stored in yellow bone marrow | Potential energy reserve
What are the Proximal & distal ends of bone called?
Ephipyhses
What is the Main shaft of bone called?
Diaphysis
What Contains the epiphyseal growth plate?
Metaphyses
What Contains the epiphyseal growth plate?
Metaphysis
What Covers epiphyses | Reduces friction & absorb shock?
Articular cartilage
What Surrounds external bone surface | Osteogenic layer |
Connective tissue?
Periosteum
What houses the bone marrow?
Medullary Cavity
What lines internal bone surface?
Endosteum
What are Osteoblasts?
Form bone matrix - build bone
What are osteocytes?
Maintain bone tissue
What are osteoclasts?
Resorption of the bone matrix - dismantle the bones
What are osteogenic cells?
What cells do you need for bone homeostasis?
Osteoblasts and Osteoclasts
What percentage of the human body is comprised of spongy bone?
20%
What percentage of the human body is comprised of compact bone?
80%
What is the strongest form of bone tissue in the body?
Compact bone
Blood vessels & nerves penetrate bone via what?
Volkmann’s canals
Compact bone is arranged into structural units called?
Osteons
What is the scientific name for rings of calcified bone tissue?
concentric lamellae
What cells do Lacunae contain?
Osteocytes
What are canaliculi?
Connect osteocytes - forms intricate canal network in bone
Spongy bone contain osteocytes, osteoblasts & osteoclasts. True or false?
True
Spongy bone is arranged into Trabeculae. True or false?
True
Spaces between trabeculae help makes bones slighter. True or false?
True
Is spongy bone as strong as compact bone?
No
What is stored in the spongy bone?
Red bone marrow
Do compact and spongy bone support against weight stress?
Yes
How do Periosteal arteries enter diaphysis?
through Volkmann’s canals
Nutrient artery passes through compact bone via…
nutrient foramen
Nutrient artery divides into proximal & distal branches – Supplying what?
inner compact bone, diaphysis & spongy bone
What do Metaphyseal arteries supply?
Supply red bone marrow & metaphyses
What do Epiphyseal arteries supply?
Supply red bone marrow & epiphyses
True or False. Nutrient veins – Accompany nutrient artery | Exit in diaphysis
True
Where do periosteal veins exit?
Exit in periosteum
Where do Epiphyseal & metaphyseal veins exit?
epiphysis
Blood vessels are accompanied by…
sensory nerves
What is Endochondral ossification?
Replacement of cartilage by bone
What is intramembranous ossification?
initial bone development
What are the 6 steps of Endochondral ossification?
Development of cartilage model
Growth of cartilage model
Development of primary ossification centre
Development of medullary cavity
Development of secondary ossification centres
Formation of articular cartilage & epiphyseal plate
In the Development of cartilage model, What do mesenchymal cells form?
Chondroblasts
In the Development of cartilage model, What do chondoblasts form?
Cartilage model
In the Growth of cartilage model, What is interstitial growth?
Continuous cell division of chondrocytes
In the Growth of cartilage model, What is appositional growth?
Addition of extracellular matrix material on the cartilage model – Increases thickness
In the Development of primary ossification centre,
Perichondrium forms into the?
Periosteum
In the Development of primary ossification centre,
Chondroblasts differentiate into?
Osteoblasts
In the Development of primary ossification centre, Capillaries grow in calcified cartilage inducing?
Growth of the primary ossification centre
Hyaline cartilage covering epiphyses becomes?
Articular cartilage
What is responsible for lengthwise growth of long bones?
Epiphyseal growth plate
In the Growth of cartilage model, what is appositional growth?
Addition of extracellular matrix material on the cartilage model – Increases thickness
What is Interstitial growth of cartilage?
Cartilage growth on the epiphyseal side of epiphyseal plate
What is Replacement of cartilage?
Replacement of cartilage on the diaphyseal side of the epiphyseal plate
What is the Epiphyseal growth plate?
Layer of hyaline cartilage in the metaphysis
The Epiphyseal growth plate is divided into how many zones?
4
What are the 4 zones of the Epiphyseal Cartilage?
Zone of resting cartilage - Nearest epiphysis | Scattered chondrocytes
Zone of proliferating cartilage - Larger chondrocytes | Undergo interstitial growth | Divide & secrete extracellular matrix
Zone of hypertrophic cartilage - Mature chondrocytes | Arranged in columns
Zone of calcified cartilage - Few chondrocytes | Extracellular matrix around chondrocytes has calcified | Forms diaphysis
What age does the epiphyseal growth plate close in females?
18
What age does the epiphyseal growth plate close in males?
21
What does the closure of the epiphyseal growth plate form?
Ephiphyseal line
Bone thickness increases via?
Appositional growth
What is a bone scan?
A diagnostic scanning procedure that uses a gamma camera & tracer (ingestible or injectable) to measure the radiation emitted from bones
Bone scans detect abnormalities how many months before x-ray?
3-6 months
True or False? Rate of tracer uptake is related to
amount of blood flow to bone
True
In a bone scan, hot spots arise due to increased?
increased blood flow in region
Can bone scans be used to detect bone cancer?
Yes
What does DEXA stand for and what is it used for?
Dual-energy X-ray absorptiometry used to determine bone mineral density
similar to X-Ray
Measures mineral content of bone
Used to determine osteoporosis & changes in bone
mineral density when ageing