musculoskeletal- option topic Flashcards
(31 cards)
what are the four properties of cartilage
hard, flexible, compessible, elastic
what is cartilage made of
chondrocyte cells embedded into a matrix (chondrin) which is mainly glycoprotein which is secreted by chondrocyte cells
how does cartilage get its nutrients and can it repair itself
- nutrients diffuse through the matrix to cells
- can repair itself but is slow
what are the different types of cartilage
hyaline cartilage
yellow elastic cartilage
white fibrous cartilage
what is hyaline cartilage
- long bones grow as hyaline cartilage and grdauallt turns into bone (ossify)
- coats bone ends at joints and is called articular cartilage- has parallel collagen molecules coated with smooth glycoprotein to resist wear
- makes up rings in trachea and bronchi
- high proportion of collagen fibres for added strength but is still weakest type
- blood vessels dont penetrate so nutrients diffuse leading to slow healing
what is yellow elastic cartilage
- contains yellow elastic fibres
- extra elastin within matrix for felxibilty and shape retention
- location- external ear, nose
what is white fibrous cartilage
- contains many fibres of collagen within the chondrin matrix
- gives increased tensile strength and resilence
- location- discs between vertebrae
structure of chondrocyte cells in cartialge going outer to inner
- didvidng chondrocytes
- mature chondrocytes
- matrix of chondrocytes
what are the functions of bone
- structural support in skeleton
- movement
- protection of organs
- mineral regulation- stores calcium and phosphorus, traps lead and regulates calcium
what is compact bone
surrounds most bone, is strong
- made of osteoytes
how is bone formed (ossifocation)
- begins as hyaline cartilage that hardens to form bone
- a small plate of cartilage is left near tips- articular cartilage
- cartilage cells flattern and calcium salts are deposisted around them and harden the bone
- osteoblasts secerte layers of bone matrix around cartilage
- osteoclast break down bne
- dense fibrous connective tissue surrounding bone- periosteum
what are the two types of bone
spongy and compact
what is spongy/cancellous bone
- found at ends of long bones or vetebrae
- has network of spaces containing bone marrow, flexible tissues in which blood cells are made
what is the matrix secreted by osteoblasts that holds the osteocytes made of
- 30% organic- manly collagen so reists fracture
- 70% inorganic- manly hypoxyapatite (calcium and phosphorus salt) which resits compression
together resist twisting and sheer forces
what makes up the haversian system in compact bone
- built in concentric rings or lamellae, around a haversian canal
- osteoblasts secrete the hydroxyapatite that make lamallae which sit in the spaces called lacunae
- canaliculi are channels that radiate out of the lacunae into the bone lamallae- they process the osteoblasts which bathe in fluid derived from blood vessels in the haversian and volkmann canal
what is the haversian canal
contains an arteriole, a venule, lymph vessel, nerve fibre
what is volkamann canal
carry blood vessels from the bone surface through to haversian canals in the centre of each system
what are the two ways osteoblasts get nutrients and remove waste
- matrix of lamellae is slightly permeable so food and o2 brough by blood diffuses through bone to cells
- the fluid and the processes from osteoblasts in the canaliculi exchange material as it runs through bone matrix and neighboroughing lacunae making a three dimenstional network
what is the structure of compact bone
- haversian canals (osteons)- channel through bone containing blood vessels, lymph vessels and nerves
- canaliculi- fine threads of cytoplasm which connect the cells to the haversian canals for material exchange
- osteocytes- bone cells
- lamella- a ring of oseocytes and collagen fibres
what is rickets
a disease in which minerals are not adequately absored into the childs bones while the bones are still growing
whats the symptoms of rickets
- enlarged wrists
- bones break easily
- low calcium blood levels (hypcalcemia)
- bowed legs
/knock knees - childs physical growth height affected
- spinal, pelvic, cranial deformities
what are the causes of rickets
- lack of calcium- milk, leafy greens
- lack of vitamin D- eggs, fish, red meat
what are the risk factors of rickets
sunlight- children have to dpenden on nutrition due to lack of sun
malnutrition- common in areas of drought and starvation
what is rickets in adults
osteomalacia
