Exam 2 Study Guide Flashcards
What is the Skeletal System?
- an organ system with tissues that grow and change throughout life
- includes: bones, cartilages, ligaments, and other supportive CT
What are the functions of cartilage? What are the 3 different of cartilages?
Functions: Supports body movement and protects body
1. Hyaline
2. Fibrocartilage
3. Elastic
What is the function of Hyaline Cartilage and where is it found?
Function: supports movement of joints between bones
- most common, but also the weakest cartilage
Located in: nose, articular cartilage of a joint, costal cartilage
What is the function of Fibrocartilage and where is it found?
Function: serves as a cushion within joints to bear weight/resistance
Located in: cartilage of intervertebral disc and meniscus (pad like cartilage in knee joint)
What is the function of Elastic Cartilage and where is it found?
Function: supports flexibility of body parts that need to move
Located in: external ear
Bone Covering: What is the Periosteum and Endosteum
Periosteum: irregular CT, covers external surfaces
Endosteum: covers internal surfaces
What are the Classifications for bones?
- long
- short
- flat
- irregular
- pneumatic
- sesamoid
What is the function of Long Bones?
- provide stability, structure and strength
- made up of epiphysis (2) and diaphysis (1)
ex. humeros, femur (thigh), radius (connected to thumb in forearm), Ulna (lower forearm), tibia & Fibula (legs), and
What are Short Bones?
- enable concentrated movement/articulation
- mobility, strength & support
- short and can be of any shape
ex. carpal and tarsal bones (cuboid, cuneiform, scaphoid, trapezoid etc.)
What are Flat Bones?
- Flat appearance, 2 prominent surfaces, form boundaries of certain body cavities
- made up of 2 compact bones on the outer surface and spongy bone in the middle (sandwich)
ex. scapula, ribs, sternum etc.
What are Irregular Bones?
- shape is irregular and do not fit any category in shape
ex. vertebrae, hip bones and bones in the base of skull
What are Pneumatic Bones?
- have an irregular shape but they have large air spaces that make them lightweight and are found in the skull
- help with resonance of sound and as air conditioning chambers for inspired air
ex. skull, sphenoid, ethmoid, and maxilla
What are Sesamoid Bones?
- in the form of nodules embedded in tendons and joint capsules
- ossification takes place after birth
ex. patella, pisiform and fabella
What are Osteoprogenitor cells?
STEM cells that become osteoblasts
What are Osteoblasts?
- IMMATURE
- Secrete osteoid which hardens & produces new bone
- many become osteocytes
What are Osteocytes?
- MATURE bone cells
- trapped in a matrix (vomit capsule) & forms callus
What are Osteoclasts?
- get rid of excess bone
- remodeling of bone/callus
What is Intramembranous Ossification? Name the 4 steps!
- when cartilage develops into bone from mesenchyme or fibrous tissue
1. Ossification center forms w/ in thickened region of mesenchyme
2. Osteoid undergoes calcification
3. Woven (primary) bone and surrounding periosteum form (immature)
4. Lamellar (mature) -> 2 compact & 1 spongey
What are the 4 steps of Intramembranous Ossification?
When bone develops from mesenchyme or fibrous tissue
1. Ossification center forms w/ in thickened regions of mesenchyme
2. Osteoid undergoes calcification (calcium salts being deposited on osteoid and entrap osteoblast
3. Woven (primary) bone and surrounding periosteum form (IMMATURE)
4. Lamellar (MATURE) 2 compact and 1 spongey
What is a callus and how is it remodeled?
A callus form to heal a fracture and osteoclasts remodel it and leave a bump.
What are the major sets of blood vessels of the bone and what do they supply?
- Nutrient Artery: main blood vessel that enters the diaphysis. Supply bone marrow in medullary cavity
- Metaphyseal: enters at the metaphyses to supply blood to the spongey bone
- Epiphysial: enters at the epiphyses and supply red bone marrow and spongey bone
- Periosteal Arteries: supplies blood to outer compact bone via haversian canals of osteons
- Venous system: drains blood away from the bone
What makes up the Axial Skeleton?
- vertebral column
- thoracic cage (ribs)
- skull
How many bones in human adult?
206
Axial: 80
Appendicular: 126
How many bones are in the skull?
22
Facial: 14 no contact w/ brain
Cranial: 8 contact w/ brain
What are the Cranial Bones?
PESTOF
- Parietal (2)
- ethmoid
- sphenoid
- temporal (2)
- occipital
- frontal
What are the Facial Bones?
VAIN
- vomer
- auditory ossicles
- inferior nasal concha
- nasal bone
MM
- maxilla
- mandible
PLZ
- palatine
- lacrimal
- zygomatic
What are the bones associated with the skull?
- Auditory Ossiclele (malus, incus, stapes)
- Hyoid: located inferior to mandible, attachment site for tongue and muscles of larynx used in swallowing
What are the 4 sutures?
Where do they all meet?
- Coronal
- Lambdoid
- Sagittal
(1-3 fuse in late 20’s-30’s) - Squamous (fuse in 60’s)
They all meet at the Pterion (weakest part of skull)
What are fontanels and their 2 roles when they ossify.
Holes in the skull that are made up of dense regular CT
1. Anterior: ossifies @15m
2. Posterior: ossifies @ 9m
Two main roles:
1. All skull to get bigger for growing brain
2. Allows for passage through the vagina (molding of head)
What is the Thoracic Cage? How many ribs are there?
Bone frame around the chest
- 24 ribs in total
True Ribs: 1-7 that touch the sternum
False Ribs: 8-12 don’t touch the sternum
Floating ribs: 11-12 don’t touch anything
What are the landmarks of the scapula?
Articultion: Glenoid cavity where the head of the humerous sits
- 3 borders (superior, lateral and medial) and 3 angels (superior, inferior, and glenoid cavity at lateral angle)
- spine, acromion process
Discuss: Arthritis, Craniosynostosis, kill blow, and cleft palate
Arthritis: Rheumatic disease that affects synovial joints
Craniosynostosis: congenital defect that causes one or more sutures on a baby’s head to close earlier than norma
kill blow: When the Ethmoid bone penetrating the brain.
Cleft Palate: When the palate does not fuse together properly in a a developing baby.
What are the structural classes of joints/articulation
- Fibrous: Bones held together by collagen fibers
- Cartilaginous: bones held together by cartilage and bone separated by fluid
- Synovial: bones ends are covered with articular cartilage
What are the functional classes of joints and how do they move?
- Synarthroses: immobile joints (MOST STABLE)
- Amphiarthroses: slightly mobile joints mobile joints
- Diarthroses: FREELY mobile joints (NOT STABLE)
Compare Symphysis Gomphosis and Sychondrosis Syndesmosis
Symphysis (BONES JOINED BY FIBROUS CT) Gomphosis: where teeth articulates between maxilla and mandible
ex. front root of tooth -> alveolar process of mandible
Sychondrosis (BONES JOINED BY HYALINE CARTILAGE) Syndesmosis: Between parallel bone. Also known as “interosseous membrane”.
ex. between ulna and radius so the two bones can move as one
Describe the following Synovial Joint: Condyloid, Ball and Socket, Saddle, and Hinge
Condyloid: in metacarpals
Ball and socket: move in all axis ex. hip and shoulder
Saddle: move in multiple axis ex. carpal and metacarbal bones
Hinge: movement on one axis -> allows flexion and extension ex. elbow
How does the femur articulate?
The femoral head of the proximal femur articulates with the acetabulum of pelvis. Femur head= ball
Acetabulum = socket
also aarticultes with patella & tibula
What is the pelvic girdle?
- strongly attached to axial skeleton (sacrum)
- deep sockets
- more stable than pectoral girdle
- less freedom of movement
What bones make up the Os Coxae?
Hip bone made up of 3 separate bones in childhood which fuse (IPI)
1. Ilium
2. Pubis
3. Ischium
