Skeletal System Flashcards
Function of skeletal system (bones, joints and muscles)
- forms body framework
- enables body to move
- protects and supports internal organs
- stores calcium, magnesium and produces blood cells
What type of tissue is the bone?
4 functions of the bone:
the bone is a specialised type of connective tissue
functions:
- haematopoiesis: formation of blood cells from haematopoietic stem cells found in bone marrow
- lipid and mineral storage: bone is a reservoir holding adipose tissue within the bone marrow and calcium within the hydroxyapatite crystals
- support: bones from the framework and shape of the body
- protection: protects esp axial skeleton which surrounds major organs of body
What components can bone be divided into?
- cellular components (osteoblasts, osteocytes and osteoclasts)
- extracellular matrix (ECM): molecules that provide biochemical and structural support to the cells
three types of cells in bones + explain:
osteoblasts: synthesize osteoid (uncalcified / unmineralized ECM). This later becomes calcified / mineralized to form bone.
osteocytes: As osteoid mineralizes, osteoblasts become entombed between lamellae in lacunae where they mature into osteocytes. They then monitor the minerals and proteins to regulate bone mass
osteoclasts: derived from monocytes, reabsorb bone by releasing H+ ions and lysosomal enzymes.
Large and multinucleated.
Balance of osteoblast to osteoclast activity is crucial in maintenance of tissue’s structural integrity.
It also plays a role in conditions like osteoporosis
Describe long bones (parts and the inside)
top: Epiphysis
- proximal (top) and distal (bottom)
- has spongy bone
- has red bone marrow (in infant bones and adult flat bones)
- articular cartilage (on top): thin flexible substance that provides protection at movable points
middle: diaphysis
- medullary cavity: contains yellow bone marrow (in the middle)
- compact bone on either side of medullary cavity covered by periosteum
metaphysis: space between epiphysis and diaphysis
label a full skeleton
Describe the vertebral column
5 sections, types and degrees of curvatures , spine disorders
- cervical vertebrae (7) : 2 degrees curvature
- thoracic vertebrae (12) : 1 degree
- lumbar vertebrae (5): 2 degrees
- sacrum (1) and coccyx (1) : aka sacral curvature 1 degree
primary curvature: present from fetal life (thoracic and sacral
secondary : develops later on in childhood (cervical and lumbar
scoliosis: crooked back, abnormal lateral curvature
kyphosis: hunchback, abnormal increase in thoracic curvature
lordosis: hollow back, abnormal increase in lumbar curvature
What is a sinus? 4 types?
sinus: cavities that reduce the weight of a bone
- frontal sinus (forehead next to eyebrows)
- ethmoid sinuses (glasses nose place)
- maxillary sinuses (next to long bit of nose)
- sphenoid sinuses (between eyes)
Skull
no. of bones, connected by
2 parts of the skull
- 22 bones or 29 including inner ear and hyoid bones
- connected by: sutures
- neurocranium (8 bones) : protects brain
occipital, frontal, sphenoid (outer side of eye), parietal (2), temporal (2), ethmoid (eye corner) - viscerocranium (14 bones) : facial and jaw bones
mandible, maxilla (2), vomer, inferior nasal concha (2), palatine (2), nasal (2), lacrimal (2), zygomatic (2)
2 parts of the neurocranium
cranial roof: (calvarium)
frontal, occipital, 2 parietal bones
cranial base:
frontal, sphenoid, ethmoid, occipital, parietal and temporal
Cranial Fossae
- anterior cranial fossa
- middle cranial fossa
- posterior cranial fossa (next to foramen magnum hole)
Most important cranial sutures
- coronal: between frontal and parietal bones
- sagittal: between parietal bones
- lambdoidal: runs horizontal between occipital and parietals
Label vertebral structure
- spinous process
- transverse process
- lamina
- vertebral arch
- vertebral foramen (spinal cord)
- superior articular process and facet
- pedicle
- body (centrum)
Chest Bones (thoracic cavity)
- clavicle (collar bone)
- scapula (shoulder blade connecting scapula to humerus)
- sternum:
jugular notch, clavicular notch
manubrium
angle of louis (sternal angle)
facets for ribs (costal cartilages)
The body (gladiolus)
xiphisternal joint, xiphoid process - ribs:
true ribs: attach directly to sternum
false ribs: attach to 7th costal cartilage
floating ribs: no anterior attachment
Bones of the pelvis
- ilium
- ischium
- pubes
- pelvic cavity (pubic symphysis where both pubic bones join
