Chapter 6 Flashcards
Skeletal system
provides a framework that supports the body
protects some internal organs from injury
contains and protects red bone marrow
provides a storage site for excess calcium
Bones
Bone cells are called osteocytes
Matrix-calcium salts and collagen
joint surfaces of bones are covered with articular cartilage; covering the rest of the bone is the periosteum
Two types of bone tissue
Compact bone- made of osteons or Haversian systems
Spongy bone- contains osteocytes and bone matrix but not arranged in Haversian systems. Cavities contain red bone marrow.
Long Bones
arms, legs, hands, and feet
each consists of a diaphysis made of compact bone and epiphyses made of spongy bone
the marrow canal contains yellow bone marrow
Short bones
wrist and ankles bones
made of spongy bone covered with a thin layer of compact bone
the spongy bone contains red bone marrow
Flat bones
ribs, shoulder blades, hip, and cranial bones
made of spongy bone covered with a thin layer of compact bone
the spongy bone contains red bone marrow
Irregular bones
the vertebrae and facial bones
made of spongy bone covered with a thin layer of compact bone
the spongy bone contains red bone marrow
Embryonic growth
Osteoblasts- cells that produce bone matrix
Ossification- hardening of bone
Fontanels- permit compression of the baby’s head during birth without breaking the still thin cranial bones
Epiphyseal discs- occurs in long bones
Osteoclasts- destroying cells
Growth Hormone (anterior pituitary gland)
•Increases the rate of mitosis of chondrocytes and osteoblasts
• Increases the rate of protein synthesis (collagen, cartilage matrix, and enzymes for cartilage and bone formation)
Thyroxine (thyroid gland)
•Increases the rate of protein synthesis
• Increases energy production from all food types
Insulin (pancreas)
Increases production from glucose
Parathyroid hormone (parathyroid glands)
• Increases the reabsorption of calcium from bones to the blood (raises blood calcium level)
• Increases the absorption of calcium by the small intestine and kidneys (to the blood)
Calcitonin (thyroid gland)
• Decreases the reabsorption of calcium from bones (lowers blood calcium level)
Estrogen (ovaries) or testosterone (testes)
• Promotes closure of the epiphyses of long bones (growth stops)
• Helps retain calcium in bones to maintain a strong bone matrix
The skeleton
Axial Skeleton- which forms the axis of the body
Appendicular skeleton- which supports the appendages or limbs
206 bones in total
Skull
8 cranial bones and 14 facial bones
3 small bones in each middle ear cavity
Frontal
•air cavity that opens into nasal cavity
•joint between frontal and parietal bones
Parietal
•Joint between the 2 parietal bones
Temporal
•Joint between temporal and parietal bones
•The tunnel-like ear canal
•Oval projection behind the ear canal
•Air cavity that opens into middle ear
•Oval depression anterior to the ear canal; articulates with mandible
•Anterior projection that articulates with the zygomatic bone
Occipital
•large opening for the spinal cord
•Oval projections on either side of the foramen magnum; articulate with the atlas
•Joint between occipital abdominal parietal bones
Sphenoid
•Flat, lateral portion between the frontal and temporal bones
•central depression that encloses the pituitary gland
Ethmoid
•Air cavity that opens into nasal cavity
•Superior projection for attachment of meninges
•On either side of base of crista galli; olfactory nerves pass through foramina
•upper part of nasal septum
•Shelf-like projections into nasal cavities that increase surface area of nasal mucosa
Mandible
•U-shaped portion with lower teeth
•Oval projections that articulate with the temporal bones
•Conical depressions that hold roots of lower teeth
Maxilla
•Air cavity that opens into nasal cavity
• Projection that forms anterior part of hard palate
• Conical depressions that hold roots of upper teeth
Nasal
from the bridge of the nose
Lacrimal
•opening for nasolacrimal duct to take tears to nasal cavity
Zygomatic
•form point of cheek;articulate with frontal, temporal, and maxillae
Palatine
•form the posterior part of hard palate
Vomer
•Lower part of nasal septum
Ribs
first seven pairs- true ribs-connect to the sternum
next 3 pairs-false ribs-their cartilage join the 7th rib
last 2 pairs-floating ribs-they do not articulate with sternum at all
protects heart and lungs liver and spleen
Synarthrosis (immovable)
Suture-fibrous connective tissue between bone surfaces
Amphiarthrosis (slightly movable)
Symphysis-disc of fibrous cartilage between bones
diathrosis (freely movable)
Ball and socket
Hinge
condyloid
pivot
gilding or planar
saddle
Ball and socket
movement in all planes
Ex:Scapula and humerus
pelvic bone and femur
Condyloid
movement in one plane with some lateral movement
Ex:Temporal bone and mandible
Hinge
movement in one plane
Ex: Humerus and ulna
• Femur and tibia
• Between phalanges
Pivot
Rotation
Ex:Atlas and axis
radius and ulna
Gliding or planar
side to side movement
Ex:Between carpals
sacrum and illium
Saddle
Movement in several planes
carpometacarpal of thumb
Synovial joints
All diarthroses are synovial joints
On the joint surface is articular cartilage which provides a smooth surface
The joint capsule
made of fibrous connective tissue, encloses the joint in a strong sheath
stabilizes the joint
synovial membrane lines the joint capsule
Synovial fluid
is in the the synovial membrane
thick and slippery and prevents friction as bones move
bursae
which are small sacs of synovial fluid between the joint and the tendons that cross over the joint
bursitis- when bursae is inflamed and painful
Arthritis
inflammation of a joint
two types: osteoarthritis and rheumatoid arthritis
Osteoarthritis
natural consequence of getting older
articular cartilage is gradually worn away
Rheumatoid arthritis
crippling disease that may begin i. the early middle age or less commonly during adolescence
autoimmune disease
foramen
a hole or opening
fossa
a depression
crest
a ridge or edge
meatus
a tunnel like cavity
process
a projection
facet
a flat projection
condyle
a rounded projection
plate
a flat projection
tubercle
a round projection
Vertebral column
7 cervical vertebrae, 12 thoracic, 5 lumber
5 sacral fused into 1 sacrum
4-5 small coccgeal vertebrae
7 cervical vertebrae
those within the neck
1st vertebrae is called the atlas
2nd vertebrae is the axis
remaining 5 vertebrae do not have names
thoracic vertebrae
articulate (forms joints) wit the ribs on the posterior side of the trunk
Lumbar vertebrae
largest and strongest bones of the spine and are found in the small of the back
Paranasal sinuses
air cavities located in the maxillae and frontal, sphenoid and ethmoid bones
mastoid sinuses
air cavities in the mastoid process of each temporal bone, they open to the middle ear
3 auditory bones: malleus, incus and stapes
coccyx
the remnant of tail vertebrae and some muscles of the perineum (pelvic floor) are anchored to it
natural curves of spine
Cervical curve-forward
thoracic curve-backwards
lumbar curve-forward
sacral curve-backward
