Skeletal System Flashcards
What is the diaphysis portion of bone?
The long main portion of the bone
What is the epiphysis portion of a bone?
The ends of the bone
What is the metaphysis region? What does this region contain?
Region between diaphysis and epiphysis. Contains the epiphyseal growth plate
What is the epiphyseal growth plate? Once growing is done what does it turn into?
A cartilaginous area within the metaphysis of a growing bone. Once growing stops you are left with an epithelial line
If on an X-ray you see epiphyseal growth plate what does that tell you about the bone?
There is potential for that bone to grow
What is the periosteum? What is its function?
Tough connective tissue that covers and surrounds bone
Nourishes, protects and heals bone
Attachment point for tendons and ligaments
How is the periosteum structured? I.e. Layers
Outer layer tough which supports and protects
Inner layer ha bone forming cells
Well vascularised and innervated
What is articular cartilage?
A layer of hyaline cartilage that covers epiphyses
What is bone made up of %
25% water
25% collagen
50% mineral salts
Bones medullary cavity is also known as?
What is it? What does it contain?
Aka marrow cavity
It is space within the diaphysis that contains red marrow (for blood cell formation) and yellow marrow (for fat storage)
Which bones have red marrow?
Pelvis, vertebrae, ribs, breastbone, skull, proximal ends of femur and humerus
What are osteoprogenitor cells? Where are they found?
Cells line inner portion of periosteum, not yet osteoblasts but when they are needed they will turn into them. Active during normal growth healing and cyclical bone replacement.
What are osteoblasts?
Bone building cells. They build bone all around them and then just maintain
What are mature bone cells called?
Osteocytes
What are osteoclasts?
Bone eating cells. They break down old bone that needs to be replaced
What are two types of bone?
Compact and spongey
Where is compact bone found? What’s its function?
It is the external layer of all bones. Provides protection and support
What makes up compact bone?
Osteon aka Haversian systems
What is the central canal in a bone?
A hole through centre of osteon through which blood and lymphatic vessels run.
What are concentric lamellae?
Rings of hard calcified bone matrix around the central canal
What are lacunae?
Spaces between the rings that circle the central canal.
In the lacunae are osteocytes
What are canaliculi?what are they filled with?
Small channels sticking out in all directions from the lacunae. They are filled with extra cellular fluid and allow osteocytes to communicate
What is volkmann’s canal? What is it also known as?
Aka transverse perforating canals. Holes which run transversely to connect the inner and outer portions of the bone.
What is spongey bone also known as?
Cancellous bone
What are features of spongey bone?
Lighter
Spaces can contain red bone marrow
Designed for lower stresses or stresses from different directions
Trabecular contain osteocytes in lacunae connected by canaliculi
Are bones vascularised or not?
Yes, well vascularised
What are the different ways bone is supplied with blood?
Periosteum arteries enter the diaphysis at multiple points (volkmann’s canals) to supply the periosteum and outer compact bone.
Nutrient arteries enter the diaphysis via nutrient for amen to supply inner compact bone, spongey bone and red bone marrow
Which arteries supply the metaphysis? Epiphysis?
Metaphysical arteries, epiphyseal arteries
What are the three stages of bone growth?
Birth, adolescent growth, loss
Where does long bone grow from? Where do they get thicker?
Lengthens from the epiphyseal growth plates.
They get thicker by osteoblasts in periosteum laying new bone at the periphery
What are the functions of bone?
Support Protection Movement Blood cell production Mineral homeostasis Storage
