Module 2 - Skeletal system Flashcards
what do the following prefixes mean:
intra-
meso-
peri-
intra= within
meso= middle
peri= around
what do the prefixes os/osteo mean
bone
what do the following suffixes mean:
-blast
-clast
-cyte
blast= create/ to form
clast= breakdown
cyte= cell
what are 4 connective tissues related to the skeletal system
- bone
- cartilage
- tendons
- ligaments
what are the 5 function of connective tissue that relate to the skeletal system
- connects
- supports moving parts
- protection (bone protects immune cells)
- store compounds (calcium and phosphate)
- enclose separate tissues (eg. periosteum)
what are the 2 function of connective tissue that dont relate the the skeletal system
- cushioning and insulation
- transportation
what are the 6 major functions of the skeletal system
- assists with movement
- support
- protection
- mineral homeostasis
- blood cell production
- triglyceride storage
what are chondroblasts
cells that make cartilage
what are chondrocytes
cells that maintain the extracellular matrix and produce the matrix
what are the mature and immature cartilage cells
chondroblasts are immature
condrocytes are mature
what is lacunae
spaces in the cartilage matrix that host chondrocytes
what is the structure of cartilage
matrix (dense network of collagen and elastic fibres)
and fluid
note- it is fairly metabolically inactive and there is no direct blood supply
what are the key features of cartilage
- avascular (nutrients comes from underlying bone)
- no nerves
- cartilage cells are formed from cells in the perichondrium (connective tissue covering cartilage) + these cells produce the matrix
describe the 2 types of cartilage growth
Appositional growth - cartilage added to the outside
Interstitial growth - chondrocytes within matrix divide and add more matrix between them
name the 3 types of cartilage and where are they needed
hyaline - areas where strong support and flexibility is needed
fibro - areas with lots of mechanical pressure (+mechanical stress)
elastic - where flexibility but rigidity is needed
what are the characteristics of hyaline cartilage
- gelatinous, glossy cartilage with evenly distributed collagen fibres
- found in ribcage and bronchi
what are the characteristics of fibrocartilage
- more collagen bundles than hyaline
- slightly compressible and very tough
- found in the knee, jaw, intervertebral disks
what are the characteristics of elastic cartilage
- matrix is similar to hyaline but has the addition of lots more elastic fibres
- somewhat flexible
- rigid
- found in external ear, epiglottis, auditory tubes
Describe the relationship between cartilage cells
- chondroblasts produce the matrix, once they are surrounded by it their name changes to chondrocytes and they stay in the lacunae
what are the 3 types of bone cells and what is their role
osteoblasts- bone forming cells, produce the matrix, found in the periosteum
osteocytes- maintain the matrix, located in lacunae
osteoclasts- bone destroying cells (specialised macrophages to break down matrix), large, multinucleated cells, originate in red bone marrow
how much of our bone matrix is organic and inorganic and what does this mean
35% organic and 65% inorganic
organic is made up of:
- collagen fibres and proteoglycans
- C,H,O,N
- made from carbs, proteins, lipid elements
inorganic is made up of:
- hydroxyapatite CaPO4 crystals
- Ca++ and PO4–
- made from absorbed inorganic ions
both are made by osteoblasts, the organic matter is also maintained by osteocytes
what is the process of making the bone matrix called
ossification/osteogenesis
why are mineral and collagen both needed in bone
- minerals stop it from being too bendable, collagen stops it from being too brittle
describe the 2 types of bone growth + when they are used
- woven - collagen arranged randomly - used in fetal development and initial repair
- lamellar - collagen fibres are parallel within sheets and different sheets run in different directions - replaces woven bone
what are the 2 types of bone DEVELOPMENT
- intramembranous ossification - takes place within connective tissue membrane
- endochondral ossification - takes place within cartilage template
what is the embryonic precursor cell for bone
mesoderm / mesenchymal tissue
describe the steps in forming woven bone via intramembranous development in fetal development
mesenchymal cells in connective tissue-> osteoprogenitor cells -> osteoblasts -> form woven bone
describe the process for endochondral ossification
Steps:
1.mesenchymal cells aggregate to become osteochondral progenitor cells
2. then differentiate to become chondroblasts (forming the cartilage framework)
3. blood vessels invade framework + osteochondral dells in perichondrium differentiate into osteoblasts
4. osteoblasts move into calcified cartilage framework and deposit new bone matrix
5. osteoblasts and osteocytes produce woven bone - this step continues until 18/20yrs old
what are the 2 directions of bone growth
interstitial (between) - to make them longer
appositional (on top) - to make them wider/thicker
what are the 2 types of bone
spongy and compact
describe spongy bone
- appears porous, contains columns of trabeculae
- weight bearing
- surrounded by a sleeve of compact bone
where is spongy bone found
- spine
- articulating joints
- ends of long bones
describe compact bone
- it is the strongest part of the bone
- basic unit is an osteon
- there are less osteocytes
- the osteocytes are located around the central canal not in lacunae (this is important for strength and support)
describe the composition of an osteon from innermost to outermost
- central canal
- concentric lamellae (around central canal)
- circumferential lamellae (around the surface of bone)
- lamellae interstitial (between osteons/remnants of previous osteons)
- perforating canal (connects periosteum BVs to central canal BVs
how do nutrients and waste travel within a bone
- interstitial fluid of lacunae and canaliculi (smaller canals radiating outward from central canal)
- from osteocyte to osteocyte by gap jumping
describe the path of blood flow to supply bones
- arteries pass through periosteum into medulla (the cavity with bone marrow)
- medullary arteries branch into ascending and descending
*blood moves into capillaries via perforating canals
*and move into the central canal.
what are the 4 bone classifications by shape
- long
- short
- flat
- irregular
what are the features of flat bones
- no diaphysis (shaft) or epiphyses (end knob)
- sandwich of spongy bone between compact bone
- some have sinuses
what are the features of short and irregular bones
- no diaphysis (shaft)
- whole structure is similar to the epiphysis
- compact bone surrounding spongy centre
what are the features of long bones
- have a diaphysis and epiphysis
- epiphyseal plate - hyaline cartilage between diaphysis and epiphysis ( present until growth stops and then the cartilage is replaced by bone and is call the epiphyseal line
- it has a medullary cavity that contains bone marrow
what is the difference between red and yellow bone marrow and when do we have them
children have red bone marrow everywhere
adults have red marrow everywhere except in the limb bones and skull where it turns yellow
- the difference comes from a change in adipose content
what are the 3 classes of fibrous joints and how do they join bones
suture - opposing bones interdigitate (like clasping hands) eg. coronal suture
syndesmosis - bones joined by ligaments eg. tibiofibular
gomphosis - pegs fitting into sockets eg. teeth
what are the 2 classes of cartilaginous joints and how do they join bones
synchondrosis - 2 bones joined by hyaline cartilages eg. epiphyseal plate or ribs to sternum
symphysis - 2 bones joined by fibrocartilage eg. intervertebral or symphysis pubis
what are the 3 classifications of joints
fibrous, cartilaginous, synovial
what classes of joints have NO movement and what class is freely moveable
NO movement - fibrous suture and symphysis
free movement - synovial
describe a synovial joint
- has a joint cavity filled with lubricating synovial fluid
- all contain the following structures/ features:
- bone
- articular cartilage (covering bones where there is contact)
- tendon
- joint cavity and joint capsule
- tendon
- bursa (extension of joint cavity that acts as a cushion)
what 4 features vary the stability of the synovial joint
- depth of joint cavity
- ligaments and tendons crossing the joint
- tension of muscles crossing the joint
- complementary shape of the articulating surfaces
why does the shoulder joint have less stability but more mobility than the hip joint
it has a shallow joint cavity
is calcium organic or inorganic and what form is it found in in bones, what happens if a bone is decalcified
it is inorganic because it is a mineral and it is found in hydroxyapatite,
without calcium it would be bendy
if you burnt a bone what would be left behind and how would it feel
it would leave behind the inorganic parts (organic bits burn) and the bone would be very brittle
what is the periosteum
a layer of dense irregular connective tissue surrounding the bones surface (where there is not articular cartilage) that supports blood and nerve supply.
- 2 layers: outer is fibrous and inner is a single layer of bone cells
- tendons are continuous with periosteum
what role of the periosteum
- protect the bone
- contain cells for bone formation
what is found in the central canal of an osteon
- blood and nerves
what are some flat bones that develop via intramembranous ossification
occipital, parietal and temporal skull bones
what are 2 long bones that develop via endochondral ossification
all bones in the arms and legs + phalanges
what is the bone between the temporal bone and zygomatic bone
sphenoid bone
in which bone do we find the Foramen magnum
occipital bone
in which bone do we find the External auditory meatus what is it
temporal bone - for the ear hole
where do you find the pituitary fossa or sella turcica and what is it
in the sphenoid bone, it is a saddle shaped depression that the pituitary gland sits in
identify the spinous process in a vertebrae
pointy stick out the top (pointing posteriorly)
identify the transverse processes in a vertebrae
project laterally from each side
where are the lamina and pedicle
the lamina joins the spinal process and the transverse process and the pedicle joins the body and the transverse process
what is distinguishing about lumbar vertebrae, how many do we have and what is its purpose
- large body + short spinous process
- 5
- weight and load bearing, muscle attachment
what is distinguishing about cervical vertebrae, how many do we have and what is its purpose
- small in size, have a transverse foramen (holes next to the body)
- 7
- support the weight of our head, for vertebral arteries
what is distinguishing about thoracic vertebrae, how many do we have and what is its purpose
- large round body, long spinous process, circular vertebral foramen.
- 12
- for muscle attachment and hold the spinal cord
how many sacral and coccyx vertebrae do we have
5 sacral (fused)
1 vertebrae (3-5 bones semifused)
what is the tubercle of the ribs
a small prominence on the posterior side of the rib between the head and neck that is the corresponding articulating surface to the transverse projection of the numerically equal vertebrae.
how many ribs do we have and how are they ordered
1-12 superior-inferior
what are the characteristics of high, medium and low ribs and how many do we have of each
high (1-2) tight curve, short, flat horizontally
middle (3-10) large curve, long, flattened vertically
low (11-12) slight curve, very short, flattened vertically
what are the parts of the sternum ordered superiorly to inferiorly
- manubrium
- body
- xiphoid process
what are the names of each side of the scapula is a defining difference
Costal = anterior (facing cartilage) -
Dorsal = posterior (dorsal fin)
dorsal side has the scapular spine
what is the acromion process
projection off the top corner of the scapular from the scapular spine
what does the clavicle join to medially and laterally
medial = sternum
lateral = scapula
how many carpal bones are there
8 in each hand
how many metacarpals in each hand and how are the numbered
5 - lateral to medial (thumb to pinky)
what 3 bones make up the coxal bones, and what is the common term for coxal bones/ os coxae
- Hip bones:
- pubis, ilium, ishium
which of the hip bones do you sit on
ishium
what is the pelvic girdle
the ring of bone formation of the pelvis
what is the pubic symphysis and what type of joint is it
- articulation that joins the 2 os coxae anteriorly (little gap at the front of the pelvic girdle)
- it is a cartilaginous joint that allows slight movement (childbirth)
what is the name for the heel bone
Calcaneus
how are the metatarsals numbered
medially to laterally (big toe to pinky toe)
what are the 5 types of movement that are possible at the shoulder joint
- flexion and extension
- abduction and adduction
- rotation
what factors effect bone growth
- shape and size are determined genetically
- can be influenced by: nutrition, hormones, exercise
how does lack of nutrients affect bones
- can cause bones to be smaller
what does vit D do for bones
- necessary for absorption of calcium from intestines
what does Vit C do for bones
- necessary for collagen synthesis by osteoblasts, a lack of it can causde scurvy
what is the relationship between Vit A and bones
- excess can have neg effects on bone health
how does vit K affect bones
can modify several bone matrix proteins
what is the correct blood level of Ca++
9-11mg/100ml
what are 3 function of Ca++
- release of neurotransmitters
- muscle contraction
- blood clotting (enzyme cofactor)
what are the daily requirements of calcium intake for men over and under 50 yrs
over 50 = 1200 mg / day
under 50 = 1000 mg /day
what are the daily requirements of calcium intake for women over and under 50 yrs
over 50 = 1300 mg / day
under 50 = 1000 mg / day
what factors influence the changing of bones
- activity
- stress
- Ca++ regulation
- bone repair
what are the 2 divisions of the skeletal system
Axial (80 bones) - skull, vertebral column and rib cage
Appendicular (126 bones) - arm and leg bones
what are the condyle and facet of a bone
condyle is a smooth rounded articular surface
facet is a small flattened articular surface
(they are the pivotal points)
what is a bone projection
a raised area for attachment of muscle or ligaments
what is a bone process
prominent projection
what is a tubercle
small round bump
what is a tuberosity
knob
what is a trochanter
tuberosity on proximal femur
what is an epicondyle
near or above a condyle (smooth rounded articular surface)
describe 2 key features of sutures
- periosteum is continuous between bones
- in adults they may ossify completely
what is a key feature differentiating syndesmosis from sutures
- bones are further apart and are joined by ligaments
what are the 4 movement classifications at synovial joints
- gliding
- angular (flexion or extension)
- circular (rotation, pronation vs supination, circumduction)
- combination
describe the types of circular movement at synovial joints
rotation - medial or lateral rotation
pronation - into prone position
supination - into supine position
circumduction - widest movement possible that reflects flexibility of action of joint
what are the 4 pairs of specialised movement
- elevation and depression
- protraction vs retraction (underbite vs overbite)
- inversion vs eversion
- opposition vs reposition ( touch pinky and thumb vs anatomical position)
