exam review - quiz 8 Flashcards
1
Q
name: function of skeletal system (5)
A
- support
- bone = hard + rigid
⤷ not static (breaks and repairs)
- cartilage = flexible + strong
- ligaments - bone to bone - protection
- skull = brain
- ribs, sternum, vertebrae = organ of thorasic cav. - movement
- prod. by musc. of bones via tendons - storage
- Ca and P = released as needed
- fat = stored in musc.
⤷ yellow = adipose (stores E)
⤷ red = prod. different blood cells - blood cell production
- bone marrow -> blood cells and platelets
2
Q
explain: characteristics of cartilage (cartilage matrix, cell types)
A
- firm, smooth, resilient
- non vascular (no blood supply)
- cartilage matrix = 70 - 85% water (helps w/ resilience), protein (collagen/elastic fibers), ground substance (proteoglycans that trap water)
- main cell type = chondrocyte
⤷ immature version = chondroblast - chondroblasts prod. the matrix
3
Q
name: types of cartilage (3)
A
- hyaline
- most common
- formed in emb. development
- movable, in all joints
- nose, rings of trachea - elastic
- has elastic fibers
- in auricle of ear - fibrocartilage
- lots of prot. fibers (well organized)
⤷ makes it strongest cart.
- provides support and strength
- no perichondrium
- in between vertebrae and joints
4
Q
define + explain: perichondrium
A
- perichondrium = double later of CT covering cartilage
- is nerve + blood supply
- outer layer = dense, irregular CT
- inner layer = chondroblasts
- none in articular cartilage (joints don’t need blood) and fibrocartilage
- hard to repair cart. (esp. w/out perichondrium) bc no blood supply
⤷ needs to get it from bone
5
Q
explain: growth in cartilage (2)
A
- appositional: right under perichondrium
- chondroblasts secrete matrix -> trap themselves -> become part of mature cart.
- for puberty + onwards - interstitial: more in matrix
- mature chondrocytes divide -> secretes more matrix -> pushes cells away from each other -> become independent cells
- mvt. because matrix has water
- for young -> until puberty
6
Q
explain: bone matrix
A
- bone cells = trapped in matrix
⤷ constantly break down and replace old matrix - 65% inorganic (minerals)
⤷ hydroxyapatite = calcium phosphate crystals - 35% organic (collagen + proteoglycans)
⤷ flexible strength bc water
7
Q
explain: types of bone cells (3)
A
- osteoblasts
- prod. collagen and proteoglycans -> package them into vesicles -> vesicles pushed to mem. -> release prot. to form collagen framework outside of cell
- other vesicles have calcium and phosphate -> gets released out to fill in framework -> ossifies it
- osteochondral progenitor cells: stem cells that can become osteoblasts or chondroblasts - osteocytes
- osteoblasts surrounded by bone matrix
- inactive
- maintains ability to prod. components req. to maintain bone matrix
- connects cells to allow mvt/ of nutrients between -blasts - osteoclasts
- large multinuclear cells on surface of bones
- formed from fusion of monocytes (WBC)
- resorption of bone (break down)
- secretes acids and enz.
⤷ acids break down minerals, enz. breaks down prot.
- activation -> attaches to bone w/ podosomes -> makes a sealed compartment against bone, releases A and enz., bone fragments get taken up into osteoclast -> released into extracellular space as a blood supply
8
Q
name: classification of bone tissue (2)
A
- woven bone
- randomly oriented collagen fibers
- first type in dev. and repairs
- eventually gets remodeled - lamellar bone
- mature bone org. in sheets and layers (lamellae)
- in all bones
9
Q
name + explain: types of lamellar bone (2)
A
- spongy (cancellous, trabecular)
- less bone matrix = more space
- on inside of bones
- 20% of skeleton
- protected by compact bone
- trabeculae = connecting rods or plates
⤷ oriented along lines of stress
- spaces fill w/ blood vessels and marrow
- osteocytes in lacunae between lamellae
- gets nutrients through canaliculi - compact bone
- dense (less spaces)
- on outside of all bones
- 80% of skeleton
- blood vessels in bone
- central/haversian canals = parallel to long axis
⤷ connected by perforate Voltmann canals - lamellae = rings of calcified matrix
⤷ concentric = form series of circles around blood supply
⤷ circumferential = bundle osteons together
⤷ inferential = fills spaces between circles of osteons - periosteum = 2 layers
- endosteum = connective tissue lining all internal surfaces w/in bones
10
Q
explain: structure of long bone
A
- shaft = diaphysis = mostly compact bone
- end = epiphysis = mostly spongy bone
- in between = metaphysis
- growth plate = epiphyseal plate = hyaline cartilage
⤷ until growth stops - epiphyseal line = bone stops growing
⤷ replaces growth plate - medullary cavity = in children = red, in adults = yellow
⤷ except not yellow in proximal epiphyses, pelvic bones
11
Q
explain: bone development
A
- osteogenesis
- begins in emb. at 8 wks
⤷ blood vessels stim. mesenchyme -> osteochondral progenitor cells - intramembrane ossification: bone formation in connective tissue mems.
- endochondral ossification: bone formation in cartilage
- bone prod. first -> remodeled after
12
Q
explain: types of bone growth (2)
A
- length
- zone of resting cartilage = diving chondrocytes
- zone of proliferation = new cartilage prod. -> chondrocytes form stacks
- zone of hypertrophy = chondrocytes mature + enlarge
- zone of calcification = matrix gets calcified, chondrocytes die
- finishes w/ ossified bone - thickness
- osteoblasts under periosteum lay down bone -> ridges
- ridges meet -> tunnel forms
⤷ periosteum -> end of tunnel
- osteoblasts from endosteum form new concentric lamella
- osteoblasts from periosteum form new circumferential lamella
13
Q
question: what type of growth is bone growth?
A
- appositional growth
⤷ new bone grows on surface of old bone - no interstitial bc matric is solid
14
Q
name: types of skeleton (2)
A
- axial skeleton
- 80 bones
- skull, hyoid, vertebrae, ribs, sternum, auditory ossicles - appendicular
- 126 bones
- upper + lower limbs, pelvic + pectoral girdles
15
Q
explain: bones in skull (+ charac.)
A
- protects brain
- 22 separate bones + 6 ossicles + 1 hyoid
- 2 types: cranial and facial
