The Skeletal System Flashcards
Describe the structure of hyaline cartilage
-Spherical chondrocytes
-has a perichondrium appart from the shoulders and synovial joints
Describe the function of the Hyaline cartilage
-most abundant
-support and flexability
-connects ends of bones (articular cartilages)
-connects ribs to sternum
(costal cartilages)
-supports nose in respiratory system
(respiratory cartilages)
-supports external nose (nasal cartilages)
Describe the structure of fibrocartliage
-parralel rows of chondrocytes alternating with thick collagen fibres
-high tensile strength
Describe the function of fibrocartilage
-shock absorber
-strong
-compressable
What is the axial skeleton?
consists of bones of the head and trunk of the vertebrate
What is the overall main function of the skeleton and bones?
-support for body and soft organs
-protection for spinal cord and vital organs
-movement-levers for muscle action
Name the seven important functions of the skeleton and bones
-support
-protection
-anchorage
-mineral storage
-blood cell formation
-triglyceride storage
-hormone production
What is anchorage?
skeletal muscles attaching to bones by tendons, use bones as levers to move the body and its parts.
Why is mineral storage important in bones?
most important mineral is calcium phosphate found in ground substance
The stored minerals are released into the bloodstream in their ionic form to be distributed into all parts of the body.
Why is hormone production important in bones?
bones release osteocalcin which helps regulate insulin secretion, glucose homeostasis and energy expenditure
What is a sesmoid?
embedded in tendons protecting them from stress and wear.
name 4 types of bone shape
-long
-short
-flat
-irregular
What is the appendicular skeleton?
compromises of the lower and upper extremeties.
Describe the structure of compact bone
-smooth
-solid
Describe the function of compact bone
-provides resistance
-makes RBC as it contains red marrow and trabculae
Describe the structure of spongy tissue
-trabeculae-flat spongy pieces, bones spines
-open spaces between trabeculae are filled with red or yellow bone marrow
Describe the function of spongy bone
-allow bones to be less dense
-allows for RBC formation
-puts up with the stress and strains of the bone
Where would you find the diaphysis
middle of the bone, its the main structure
Where would you find the epiphysis?
End of the bone, articulate cartilage that covers the joints
What is the epiphyseal line?
-growth plate
-a disk of hyaline cartilage that grows during childhood lengthening the bones.
Name the parts involved in the gross anatomy of the bone
-proximal and distal epiphysis
-diaphysis
-articular cartilage
-spongy bone
-epiphyseal line
-periosteum
-compact bone
-medullary cavity
What is the periosteum?
the membrane of blood vessels and nerves that wrap around your bones
-connected to bone by sharpey fibres
-lots of collogen fibres
What is the medullary cavity?
The hollow part of the bone containing bone marrow
Describe the gross anatomy of the periosteum
-yellow bone marrow
-red bone marrow
-periosteum
-sharpey’s fibres
What are the two layers in the periosteum?
-fibrous layer
-osteogenic layer
What is the osteogenic layer of the peristeum?
rich in blood cells and acts as a source of bone cells
what is the function of the endosteum?
-supply osteoclasts which remove some of the inner bone as they grow to maintain a similar level of thickness.
-lines the canals that pass throught the compact bone
-covers trabeculae of spongy bone
Describe the function of osteoclasts
-remodel or remove cells
-pushes the ruffles edge against material
-releases enzymes to dissolve the bone
Function of osteoblast?
building cell
Function of osteocyte?
-helps control the function of blast and clast cells
-sensory network for the stresses and strains on the bone
Function of bone lining cells
Squamous cells communication with osteocytes
List the microscopic structures of compact bone
-Haversian system (osteon)
-periosteum
-volkmann’s canal
-Haversian canal
-Canaliculi
-osteocytes
-lacuna
-artery
-vein
-nerve fibre
Main features of dense bone
-lacuna with osteocytes (black ovals)
-interstitial llamelae (fluid)
Function of volkmanns cannal
allows blood vessesl and nerves to enter the haversian canal
Structure and function of osteons
-thick lamellar rings-provide ridigty and mechanical support and strength
-protect vascular supply via nutrient canal
-collagen fibres offer resistance in different directions for twisting and bending
How are canaliculi formed?
1- osteoblasts secrete bone matrix
2-maintain close contact with esch other and other bone cells
3-mature osteocytes develop as matrix calcifies
What are canaliculi?
-hair cannals connecting lacunae to each other and central cananals
what are crystals of hydroxyapatite?
calcium phosphate- not very strong in crystalin form, need a lattice of bone matrix and collagen fibres to support them
structure of spongy bone
-no osteon
-irregulary arranged lamellae
-osteocytes interconncted by canaliculi
Main features of the synovial joints
-joint cavity containing synovial fluid
-articular cartilage
-inner synovial membrane
-outer fiborous layer
Structure of outer fiborous layer in the synovial joint
-lots of interlocking collogen fibres in all directions for strength
Features of the synovial fluid
-contains lubricin
-contains HCl
-Contains macrophages- control,engulf , destroy
How does the articular cartilage get its nutrients in the synovial joints?
-synovial fluid secreted by the synocial membrane provides a rich network of blood vessels providing nutrients to the AC
Name 6 types of synovial joints
-ball and socket joint
-hinge joint
-saddle joint
-pivot joint
-gliding joint
-condyloid joint
List the synovial joint accesory structures
-bursae
-fat pads
-ligaments and tendons
-menisci
What are bursae?
synovial pouches fill of synovial fluid
Function of bursae
allow bone structures to move against each other without grinding the bones and joints protecting them.
-protection in tight sections of the body allowing smooth movement
-eg in shoulders and knee
Function of fat pads
-found around the synovial joint
-store fat- made of adipose tissue
highly sensitive, highly vascularised
structure of ligaments
-dense connective tissue
-lots of collogen fibres
function of ligaments
-support synovial capsule- help prevent knee dislocation /lateral sliding
-holds bones together and supports joints
function of the menisci
-provides increased stability to the femorotibial articualtion
-distribure axial load
-absorb shock
-provides lubrication to knee joint
Menisci structure
c-shaped pad of cartilage in the knee
Structure and function of tendon sheaths
-semitubules that wrap around the tendons.
-allows tendons to smoothly move against each other
-protective and malleable sheath
