Chapter 6- Skeletal system Flashcards
what is the skeletal system?
consists of bones, and other structures that make up the joints of the skeleton
what tissues are found in the skeletal system?
bone tissue
cartilage
fibrous connective tissue (ligaments)
what are the functions of the skeleton?
- provide frame work - support body
- protect internal organs from injury
- contains and protect red bone marrow
- provide storage site for excess calcium
define bones
organ composed of 2 tissues (compact bone and spongy bone)
osteocyte cells and a matrix made up of calcium salts and collagen
what is compact bone?
solid but very structured- made up of osteons or haverison systems
what is spongy bone?
contain red bone marrow in cavities.
contains osteocytes, matrix, and blood vessels
There are 4 types of bones. what are they?
- long: arms, legs, hands, feet
- short: wrist and ankles
- flat bones- ribs, shoulders, hipbones, and cranial
- irregular bones- vertebrae and facial bones.
Long bones have a shaft which is called diaphysis and the ends are called epiphyses. Describe the diaphysis and epiphysis parts of long bones
Diaphysis: made up of compact bone and is hallow, forming a cannel within the shaft. The marrow cannel contains yellow bone marrow (adipose tissue).
epiphyses- spongy bone covered with a thin layer of compact bone.
Describe the characteristics of short, flat and irregular bones
spongy bone covered with thin layer of compact bone.
Red bone marrow.
how are bones made?
in the embryonic phase, the matrix is made via ossification and starts in a centre of ossification of each bone. the bones start as fibrous connective tissue, and then fibroblast become specialized and differentiate into osteoblasts , which produce bone matrix.
what are fontanels?
areas of fibrous connect tissues remaining between the bones of the skull in a baby.
they ossify by age 2.
Describe the growth of long bones in children
they develop centres of ossification in their epiphyses, its not complete at birth and the bones continue to grow in the epiphyseal discs.
What are osteoclasts?
special large bone cells with several nuclei and a “ruffled skirt” appearance.
secretes acid and enzymes to dissolve and digest bone matrix > process known as resorption.
* keeps to form marrow cannel in long bones and establish red bone marrow- after birth red marrow turns to yellow in the shaft, but stays red in the spongy bone of short, flat and irregular bones.
what is bone remodelling?
calcium is removed by osteoclasts to raise the blood calcium levels, or calcium salts are made and deposited by osteoblasts to lower blood calcium level.
what are 5 factors that affect bone growth and maintenance?
- heredity
- nutrition
- hormones
- chemical communication from other tissues
- exercise or stress
what is osteocalcin?
a protein created by osteoblasts, which decrease fat storage by adipose tissue and increase insulin production by the pancreas
define a “bone fracture”
Medical term for broken bone
name 6 types of fractures
- simple: bone is still in normal anatomic position
- compound: broken end of bone moved, and possibly pierced skin (risk of infection)
- greenstick- bone split longitudinally, more common in children
- comminuted- two or more intersecting breaks create several bone fragments
- impacted- bones are forced into one another
- pathologic - bone breaks without trauma.
How is Growth Hormone (from the anterior pituitary gland) involved in bone growth and maintenance?
- increases rate of mitosis of chondrocytes and osteoblasts
- increases rate of protein synthesis
How is thyroxine (from the thyroid gland) involved in bone growth and maintenance?
- increases the rate of protein synthesis
2. increases energy production from all food types
How is insulin (from the pancreas) involved in bone growth and maintenance?
- increases energy production from glucose
How is parathyroid hormone (from the parathyroid) involved in bone growth and maintenance?
- increases the reabsorption of calcium from bones to the blood.
- increases the absorption of calcium by the small intestine and kidneys (to the blood)
How is thyroxine (from the thyroid gland) involved in bone growth and maintenance?
decreases the reabsorption of Calcium from bones
How is estrogen (ovaries) or testosterone (testes) involved in bone growth and maintenance?
Estrogen: promotes closure of epiphyses of long bones
Testosterone: helps retain calcium in bones to maintain a strong bone matrix
The human skeleton has which two divisions?
The axial skeleton, which forms the axis of the body and appendicular skeleton which supports the appendages or limbs.
what is a sprain?
stretching or tearing of the ligaments of a joint and though the bone is not broken, the joint is weak and unsteady.
What grouping of bones make up the skull
(2)?
8 cranial bones and 14 facial bones.
what are the cranial bones?
frontal bones, parietal bones (2), temporal bones (2), occipital bones.
sphenoid bone and ethmoid bone form part of the braincase and the sockets for the eyes.
define osteoporosis
excessive loss of calcium from bones without sufficient replacement.
Bones become thin and brittle, and at risk for fracture.
what do you call the immovable joints between cranial bones?
sutures.
the serrated, or sawtooth, edges of adjacent bones fit into each-other.
what are paranasal sinuses?
air cavities located in the maxillae and frontal, sphenoid and ethmoid bones. They open into the nasal cavities and are lines with ciliated epithelium continuous with the mucosa of the nasal cavities.
what are the 3 auditory bones in the middle ear cavity?
the malleus
incus
stapes
what is the vertebral column?
back bone- which is made up of individual bones called vertebrae.
how many vertebras are there?
cervical: 7,
thoracic: 12
lumbar: 5
sacral fused: 5 into 1 scarum
coccygeal vertebar 4-5 fused into 1 coccyx.
what is the vertebral canal?
continuous tunnel that contains the spinal cord and protects it from mechanical injury
what do you call the fibrous tissue that cushion and absorb shock and permit some movement between vertabrae (symphysis joint)
discs
whats forms the rib cage
12 pairs of ribs and the sternum (breast bone)
what are the 3 parts of the sternum?
upper mamnubrium
central body
lower xiphoid process
describe the rib characteristics
> articulate posterior with the thoracic vertebrae
first 7 ribs are true ribs, next 3 are false ribs, last 2 are called floating ribs
encloses and protects heart and lungs, other organs
Breathing expansion
what is a herniated disc?
the nucleus pulposus is forced out, often posteriorly where it puts pressure on a spinal nerve. This causes pain and impairs function of the muscles supplied by the nerve.
what is scoliosis?
abnormal lateral curvature which may be congenital.
what is Kyphosis?
exaggerated thoracic curve- hunch back
what is lordosis?
exaggerated lumbar curve- sway back
what are the bones involved in the pelvic girdle
2 hip bones- Coxae or innominate bones
each hip bone has 3 parts: ilium, ischium and pubis.
define these parts of the scapula
1) glenoid fossa
2) spine
3) Acromion process
depression that articulates with humerus
long, posterior process for muscle attachment
articulates with clavicle
Define these parts of the clavicle
1) Acrominal end
2) Sternal end
1) articulates with scapula
2) articulates with Manubrium of Sternumn
Define these parts of the humerus
1) head
2) deltoid tubercle
3) olecranon fossa
4) capitulum
5) trochlea
1) round process that articulates with scapula
2) round process for the deltoid muscle
3) posterior, oval depression for the olecranon process of ulna
4) round process superior to radius
5) concave surface that articulates with Ulna
Define the head of the radius
articulated with the ulna
Define these parts of the Ulna
1) olecranon process
2) smulunar notch
1) fits into olecranon fossa of humerus
2) “half-moon” depression that articulates with the trochlea of ulna
which parts of the carpals make up the proximal row?
scaphoid, lunate, triquetrum, pisiform
which parts of the carpals make up the distal row?
Trapesium, Tapezoid, capitate, jamate
what is a joint?
where two bones meet, or articulate
How are joints classified?
by the amount of movement.
1) synarthrosis - immovable joint
2) amphiarthrosis- slightly movable joint
3) diarthrosis- freely moveable
True or False
All diathroses are synovial joints
yes, because they are of similar structure.
what do you call the cartilage on the joint surface of each bone, that provides a smooth surface?
articular cartilage.
What is a joint capsule?
fibrous connective tissue, encloses the joint in a strong sheath, like a sleeve.
* contributes to stability of the joint
lining the capsule is the synovial membrane- secreting synovial fluid into the cavity
Many synovial joints have bursae. what is that?
small sacs of synovial fluid between the joints and the tendons that cross over the joint.
permits tendons to slide easily as the bones are moved.
what do you call the condition in which the bursae become inflammed and painful?
bursitis.
what are some consequences of aging on bones?
loss of calcium bone matrix thining bone weakening fractures erosin
what is arthritis?
inflammation of the joint
Define osteoarthritis
smooth joint surface becomes rough and this becomes painful.
What is Rheumatoid arthritis?
autoimmune disease, that afffects the synovial membrane and joints become painful and stiff. the joint calcifies and then is fused and has no mobility at all.
Name are the parts of the pelvic bones.
illium illiac crest posterior superior iliac spine ischium pubis pubis symphysis acetabulum
what are the parts of femur
head neck greater trochanter lesser trochanter condyles
What the parts of the tibia
condyles
tibial tuberosity
anterior crest
medial malleolus
what are the parts of the fibula?
head
lateral malleolus
what are the parts of the Tarsal (7)
Calcaneus
talus
Cuboid, navicular
cuneiform
describe and provide examples of the synarthrosis joint
suture: fibrous connective tissue between bone surfaces
eg: between cranial bones and facial bones
Describe amphiarthrosis joints and provide examples
symphysis- disc of fibrous cartilage between bones
eg: between vertebrae and pubic bones
describe ball and socket diarthrosis joints
movement in all places
eg: Scapula and humerus, pelvic bone and femur
describe hinge diarthrosis joints
movement in one place
eg: humerus and ulna, femur and tibia, between phalanges
describe condyloid diarthrosis joints
movement in one place with some lateral movement
eg: temporal bone and mandible
describe pivot diarthrosis joints
rotation
eg: atlas and axis, radius and ulna
describe gliding diarthrosis joints
side to side movement
eg: between carpals, sacrum and ilium
describe saddle diarthrosis joints -
movement in several planes
eg: carpometacarpal of thumb
