Skeletal System Flashcards
1
Q
What are the functions of the skeletal system?
A
- supports the body
- facilitates movement
- protects internal organs
- produces blood cells
- stores and releases minerals and fat
2
Q
Function of cartilage
A
- provide flexible strength and support for body structures
- Unite adjacent bones/provide cushioning at joints
3
Q
Function of ligaments
A
- Strong connective tissue bands that hold bones at a moveable joint together
- Prevent excessive movements of the joint that would result in injury
- Dense regular connective tissue
4
Q
Describe long bones and give examples
A
- cylindrical (longer than wide)
- Function: levers (move when they contract)
- Central chamber in the shaft (medullary or marrow cavity)
- Eg: humerus, ulna, radius, femur…
5
Q
Describe short bones
A
- cube-like shape
- Function: stability, support and limited motion
- E.g: carpal bones, tarsal bones
6
Q
Describe sesamoid bones
A
- Sesame shape (small, round)
- Contained within tendons/joint capsules
- Function: protect tendons by preventing wear and tear when a tendon moves adj to bony surface or joint
- also important in increasing the distance between the tendon and a joint. This improves the leverage of the muscle so that it requires less energy to move the joint providing the muscle a mechanical advantage in movement.
- E.g: patella
7
Q
Describe flat bones
A
- quite thin
- curved rather than flat
- Function: serve as points of attachment for muscles and often protect internal organs
- E.g: cranial bones, scapulae, sternum, ribs
8
Q
Describe irregular bones
A
- bones that don’t fulfil the above criteria
- E.g: vertebrae, facial bones
9
Q
Main parts of long bone
A
- diaphysis: walls are cortical bone tissue
- epiphysis: trabecular bone tissue, red bone marrow in spaces of this tissue
- medullary cavity: hollow region in diaphysis (yellow bone marrow)
- metaphysis: between epiphysis and diaphysis
- epiphyseal growth plate: at junction b/n epiphysis and metaphysis. hyaline cartilage
- changes to epiphyseal line once growing stops
10
Q
What is the endosteum?
A
- membranous lining of medullary cavity
- dense irregular connective tissue
- function: bone growth, repair and remodelling
11
Q
What is the periosteum
A
- dense irregular connective tissue
- covers external surface of the bone
- has BVs, nerves, lymph vessels that nourish cortical bone tissue
- Attachment site for tendons and ligaments
- covers the entire external surface except where the epiphyses meet other bones to form joints (covered with articular cartilage (hyaline) that reduces friction and is a shock absorber)
12
Q
Describe primary ossification centre
A
- first site of bone ossification - in diaphysis (central part for short and irregular)
- typically forms prenatally
- Some bones have > 1 (e.g os coxae/vertebrae)
13
Q
What are secondary ossification centres
A
- additional ossification sites at ends of the bone
- appear postnatally (around puberty)
14
Q
How do bones grow?
A
- occurs at epiphyseal plate (hyaline cartilage)
- Longitudinal growth: cartilage forms on epiphyseal side, and diaphyseal side cartilage is ossified and it grows in length
- Rate of growth controlled by hormones
15
Q
Epiphyseal line
A
Osseuous scar of where epiphyseal plate was
16
Q
Appositional growth
A
While bones are increasing in length, they are also increasing in diameter; growth in diameter can continue even after longitudinal growth ceases.
17
Q
Appositional growth
A
While bones are increasing in length, they are also increasing in diameter; growth in diameter can continue even after longitudinal growth ceases.
18
Q
What are the 3 classes of bone markings?
A
- articulation: where 2 bone surfaces come together
- projection: projects out from bone surface. attachment points for tendons and ligaments
- depression: hole/groove in the bone that allows BVs and nerves to go through
19
Q
Types of projections
A
- Process: Prominent projection, often elongated
- Protuberance: Roughened elevation
- Spine: Pointed process
- Tubercle: Small, rounded process
- Tuberosity: Rough surface
- Crest: Ridge
20
Q
Types of articulations
A
- Head: Prominent rounded surface (ball-like)
- Facet: Flat surface
- Condyle: Rounded convex surface
21
Q
Types of depressions
A
- Fossa: Elongated basin
- Sulcus: groove
- Canal: passage in bone
- Fissure: slit through bone
- Foramen: hole through bone
- Meatus: opening into canal
- Sinus: air-filled space in bone
22
Q
What is a suture?
A
- immobile joint b/n adj bones of the skull
- narrow gap is filled with dense, fibrous conenctive tissue
23
Q
What are the sutures of the skull?
A
- Coronal suture: joins frontal bone to R and L parietal bones
- Sagittal suture: joins R and L parietal bones
24
Q
Frontal bone
A
flat bone forming the forehead
25
Parietal bone
- paired
- forms superior lateral side of the skull, convex
26
Temporal bone
- Forms inferior lateral side of skull
- External auditory canal
- Mastoid process
- Carotid canal and its openings
- Auditory ossicles
27
Occipital bone
* formen magnum
* jugular foramen
28
Sphenoid bone
Sella turcica and hypophyseal fossa
29
Ethmoid bone
- single midline bone that forms the roof and lateral walls of superior nasal cavity
- Osseous nasal septum
- Nasal conchae (superior and middle)
30
Maxillae
- paired bones that form upper jaw
- hard palate
31
Mandible
- forms lower jaw
- articulates w temporal bone to form temporomandibular joint
32
Inferior nasal conchae
- Paired
- form a curved bony plate that projects into the nasal cavity space from the inferior lateral wall
33
Hyoid bone
- Small U shaped bone in superior aspect of neck (U points posteriorly)
- independent (doesn't contact others)
- function: base for the tongue
34
Hyoid bone
- Small U shaped bone in superior aspect of neck (U points posteriorly)
- independent (doesn't contact others)
- function: stabilisation of tongue during speech and swallowing
35
Describe each region of the vertebral column and the number of bones in each region
- Cervical (C1-C7)
- Thoracic (T1-T12)
- Lumbar (L1-L5)
- Sacrum
- Coccyx
36
Structure of typical vertebrae
- body: supports body weight
- vertebral arch: 2 pedicles and 2 laminae (and intervertebral foramen)
- vertebral foramen
**processes**:
- spinous process
- transverse process
- superior articular process
- inferior articular process
37
Primary curvature
- concave anteriorly
- retained from original foetal curvature (thoracic, sacral and coccygeal regions)
38
Secondary curvature
- convex anteriorly
- Cervical and lumbar regions
- develop postnatally
39
Intervertebral disc
- nucleus pulposus: central part. High water content to resist compression and support weight bearing
- Annulus fibrosus: outer tough layer of intervertebral disc. develop postnatally
40
Sternum
- Manubrium
- Body of sternum: contains lateral notches which articulate with costal cartilage
- Sternal angle: Articulation b/n manubrium and body. Lies at level of T4/5 intervertebral disc
- xiphoid process
41
Ribs
True ribs: 1-7. articulate by their costal cartilage directly w sternum
False ribs: 8-10
Floating ribs: 11-12. Dont connect with sternum at all via costal cartilages
42
Sacrum
- auricular surface
- pelvic/anterior surface
- ventral sacral foramina
- dorsal/posterior surface
- median sacral crest
43
Clavicle
* S shaped bone on anterior side of shoulder
* Sternal end: rounded, articulates w sternum
* Acromial end: flattened, articulates w/ acromion of scapula
44
Sternum
- Spine
- Ac
