chapter three Flashcards
What is the skeletal system composed of?
bones bone marrow cartilage joints ligaments synovial membranes synovial fluid bursae
What are the 5 important functions of the skeletal system?
- bones act as the framework of the body
- bones support and protect internal organs
- joints work with the muscles, ligaments, and tendons for movement
- calcium is stored in bones
- red bone marrow is located within spongy bone
What does calcium do?
Mineral required for normal nerve and muscle function.
What does red bone marrow do?
Important role in formation of blood cells.
Describe the formation of bones?
A newborn’s skeleton begins as a fragile membrane and cartilage which turns into bones (starting at 3 months) through a process called ossification
What is ossification?
Process of new bone formation
- Osteoclasts break down old or damaged bone
- Osteoblasts help rebuild the bone
Repairs minor damage to the skeletal system during normal activity
Repairs bone after major injury (fracture)
Describe the density of bone?
Second hardest tissue in the body to dental enamel
What three functions is the bone capable of?
growth
healing
reshaping
Periosteum
tough and fibrous tissue that forms the outermost covering of the bone
Compact Bone
a.k.a cortical bone
the dense, hard, and strong bone that forms the protective outer layer of the bone
accounts for greater than 75% of body’s bone matter
Spongy Bone
a.k.a cancellous bone
porous or sponge-like that is lighter and weaker than compact bone
contains red bone marrow
a greater amount of spongy bone is associated with weak bones that are more susceptible to fracture
Where is red bone marrow typically found?
- spongy bone
- ends and inner portions of long bones (femur and humerus)
- pelvic bone
- ribs
- vertebrae of the spinal column
Medullary Cavity
central cavity located in the shaft of a long bone
surrounded by compact bone
stores red and yellow bone marrow
Medullary
pertaining to inner section
Endosteum
tissue that lines the medullary cavity
Red Bone Marrow
hemopoietic tissue that manufactures
- red blood cells
- hemoglobin
- white blood cell
- thrombocyte
Hemopoietic
pertaining to the formation of blood cells
Poietic
pertaining to the formation
Yellow Bone Marrow
fat storage area composed of fat cells
Describe bone marrow and growth?
Most bone marrow is red from birth to early adolescence.
During adolescence, red bone marrow is gradually replaced by yellow bone marrow
Cartilage
smooth, rubbery, and blue-white connective tissue that behaves as a shock-absorber between bones
more elastic than bone
makes up flexible parts of the skeleton (outer ear and the tip of the nose)
Articular Cartilage
covers the surface of bones where they articulate
makes smooth joint movement possible
protects bones from rubbing against each other
Articulate
come together to form joints
Meniscus
curved, fibrous cartilage found in some joints
found in the
- knee
- temporomandibular joint of the jaw
Diaphysis
shaft of the long bone
Epiphyses
wider end of long bone
covered with articular cartilage
Proximal Vs. Distal Epiphysis
Proximal is located near the midline of the body
Distal is located farthest away from the midline of the body
Foramen (foramina)
opening in the bone through which blood vessels, nerves, and ligaments pass
example: spinal cord passes through the foramen magnum of the occipital bone at the base of the skull
Process
normal projection on the surface of a bone that commonly serves as an attachment for the muscle or tendon
Example: mastoid process is located on the temporal bones, behind the ears
Joints
a.k.a articulations
place of union of two or more bones
What are joints classified by? (two)
construction
degree of movement they allow
Fibrous Joints
inflexible layers of dense connective tissue that hold the bones tightly together
- known as sutures in adults (allowing no movement)
- allow some movement in newborns and children, before solidification
Fontanelles
a.k.a soft spots
present on the skull of a newborn
facilitate the passage of an infant through the birth canal
allow for growth of skull during year 1
close and harden as the child matures
Cartilaginous Joints
allow for slight movement
consist of bones connected entirely by cartilage
Examples:
- ribs connect to the sternum and only allow movement when breathing
- pubic symphysis allows some movement during childbirth
Where is the pubic symphysis located?
between pubic bones in the anterior of the pelvis
Synovial Joint
created when two bones articulate to permit a variety of motion
two types:
- Ball-and-socket Joint
allows for a wide range of movement in many directions
hips and shoulders - Hinge Joints
allow movement in one direction or plane
knees and elbows
What are the components of the synovial joint?
Synovial capsule Synovial membrane Synovial fluid Ligament Bursa
Synovial Capsule
outermost layer of strong, fibrous tissue
resembles a sleeve as it surrounds the joint
Synovial Membrane
lines the capsule and secretes synovial fluid
Synovial fluid
flows within the synovial cavity
acts as lubricant for smooth movement of the joint
Ligaments
bands of fibrous tissue that form joints by connecting
- bone to bone
- bone to cartilage
complex hinge joints (knee) are made up of a series of ligaments permitting movement in different directions
Bursa
fibrous sac that acts as a cushion to ease movement in areas that are subject to friction (shoulder, elbow, knee because tendon passes over bone)
Describe the number of bones in the skeleton?
adult skeleton = 206 bones (range of 206 to 350)
divided into AXIAL and APPENDICULAR skeleton
Axial Skeleton
protects the major organs of the
- nervous
- respiratory
- circulatory
80 bones in the head and body organized into 5 parts
What are the parts of the Axial Skeleton?
- bones of the skull
- the ossicles of the middle ear
- hyoid bone (between chin and thyroid)
- rib cage
- vertebral column
Appendicular Skeleton
allows for body movement
protects organs of the
- digestion
- excretion
- reproduction
126 bones divided into two parts
What are the parts of the Appendicular Skeleton?
- upper extremities (shoulders, arms, forearms, wrists, hands)
- lower extremities (hips, thighs, legs, ankles, feet)
Appendage
anything attached to a major part of the body
Appendicular meaning?
referring to an appendage
Extremity
terminal end of the body (arm and leg)
Bones of the Skull
8 bones that form the cranium
14 bones that form the face
6 bones in the middle ear
Bones of the Skull
8 bones that form the cranium
14 bones that form the face
6 bones in the middle ear
Bones of the Cranium
cranium = portion of the skull enclosing and protecting the brain
joined together by jagged fibrous joints (sutures)
What are the 8 bones of the cranium? and the meatus?
1. frontal bone 2/3. parietal bones 4. occipital bone 5.6. temporal bones 7. sphenoid bone 8. ethmoid bone
external auditory meatus
Frontal bone?
the anterior portion of the cranium forming the forehead
houses frontal sinuses
forms
- the roof of the ethmoid sinuses
- nose
- part of the socket that protects the eyeball
Parietal Bones
two of the largest bones of the skull
form the roof and upper sides of the cranium
Occipital bone
forms the back part of the skull
forms the base of the cranium
Temporal Bones
forms the sides and base of the cranium
Sphenoid Bone
irregular and wedge-shaped bone at the base of the skull
makes contact with ALL other cranial bones
helps form
- the base of the cranium
- sides of the skull
- floors and sides of the eye sockets
External Auditory Meatus
opening of the external auditory canal of the outer ear
= the canal is located within the temporal bone on each side of the skull
Meatus
external opening of a canal
Ethmoid Bone
light and spongy bone located at the roof and sides of the nose
separates nasal cavity of the brain
forms portion of each orbit
Orbit
bony socket that surrounds and protects each eyeball
Auditory Ossicles
three tiny bones in each middle ear
- malleus
- incus
- stapes
Sinus
air-filled cavity
lighten weight of skull
What are the 14 facial bones?
1/2. nasal 3/4. zygomatic 5/6. maxillary 7/8. palatine 9/10. lacrimal 11/12. inferior conchae 13. vomer 14. mandible
Nasal Bone
form upper part of the bridge of the nose
Zygomatic Bone
a.k.a cheeckbone
articulate with the frontal bone that makes up the forehead
Maxillary Bone
form ost of the upper jaw
a.k.a maxillae
Palatine Bone
form anterior of the hard palate of the mouth
form the floor of the nose
Lacrimal Bone
make up part of the orbit at the inner angle
Inferior Conchae
thin, scroll-like bones that form part of the interior of the nose
Vomer Bone
form base of the nasal septum
Nasal Septum
cartilage wall that divides the two nasal cavities
Mandible
a.k.a jaw bone
only movable bone in the skull
attached to skull at the temporomandibular joint (TMJ)
Thoracic Cavity
a.k.a rib cage
bony structure protecting heart and lungs
consists of the
- ribs
- sternum
- upper portion of the spinal column from the neck to diaphragm
The Ribs
a.k.a costals
12 pairs that attach posteriorly to the thoracic vertebrae
The first seven pairs are TRUE RIBS and attach anteriorly to the sternum
The next three pairs are FALSE RIBS and attach anteriorly to cartilage that connects them to sternum
The last two pairs are FLOATING RIBS and they attach posteriorly to vertebrae
Sternum
a.k.a breast bone
flat, dagger-shaped bone located in the middle of teh chest
connects with the ribs to form the front of the rib cage
What are the parts of the sternum?
- manubrium
- body of the sternum (gladiolus)
- xiphoid process
Manubrium
bony structure that forms the upper portion of the sternum
Body of the Vertebrae
bony structure that forms the middle portion of the sternum
Xiphoid Process
structure made of cartilage
forms the lower portion of the sternum
Xiphoid meaning
straight sword (Greek word)
Pectoral Girdle
a.k.a shoulder girdle as it is formed by the shoulders
supports the arms and the hands
Girdle
a structure that encirlces the body
What are the bones of the shoulder?
Clavicle
Scapula
Acromion
Clavicle
a.k.a collar bone
slender bone connecting the manubrium (of sternum) and the scapula
Scapula
a.k.a shoulder blade
Acromion
extension of the scapula that forms the highest point of the shoulder
What are the parts of the arm?
Humerus
Radius
Ulna
Olecranon Process
Humerus
bone of the upper arm
Radius
the smaller and shorter bone of the forearm
thumb side
Ulna
larger and longer bone of forearm
the proximal end of the ulna articulates with the distal end of the humerus to form the elbow
Olecranon Process
a.k.a funny bone
large projection on the upper end of the ulna
forms the point of the elbow
exposes a nerve that tingles when struck
The Wrist
formed of 8 carpals
form a narrow bony passage called the carpal tunnel
Carpal Tunnel
where the nerves and tendons of the fingers pass through to reach the hand
Example: Carpal Tunnel Syndrone
Palm
fomrmed by 5 metacarpals
Fingers
Formed by 14 phalanges
Fingers
- distal phalanges
- middle phalanges
- proximal phalanges
Thumb
- distal phalanges
- proximal phalanges
Spinal Column
a.ka vertebral column
protects the spinal cord
supports head and body
26 vertebrae (vertebra)
Body of the Vertebra
anterior portion of the vertebra
solid and provides strength
Lamina
the posterior portion of the vetrebrae
where the transverse and spinous processes extend from
serves as attachment for muscles and tendons
Vertebral Foramen
opening in the middle of the vertebra
allow the spinal cord to pass through
protects the spinal cord
Intervertebral Disks
made of cartilage
separate and cushion vertebrae from each other
act as shock absorbers
allow for movement of spinal column
Cervical Vertebrae
7 vertebrae
form the neck
C1 - C7
Thoracic Vertebrae
12 Vertebrae
Each vertebrae has a pari of ribs attached to it
Forms the outward curve of the spine
T1-T12
Lumbar Vertebrae
5 vertebrae
form inward curve of lower spine
largest and strongest vertebrae beraing most of the body’s weight
L1-L5
Lumbar Meaning
relating to the part of the back and sides between the ribs and the pelvis
Sacrum
slightly curved and triangular-shaped bone near base of lumbar spine
is composed of 5 bones that fuse in the young child
Coccyx
a.k.a tailbone
form end of the spine
made up of 4 vertebrae that are fused
Coccyx meaning
Cuckoo (Greek Word)
shape resembled a cuckoo’s beak
Pelvis
a.k.a bony pelvis
protects the internal organs
supports the elowe rorganas
Pelvic Girdle
the Pelvis includes it
cup-shaped ring at the lower end of the trunk
- ilium
- ichium
- pubis
Ilium
broad and blade-shaped bone that forms the back and sides of the public bone
Sachroiliac
slightly movable joint between the sacrum and posterior portion of the ilium
Ischium
form lower posterior portion of public bone
bear body weight when sitting
Pubis
form anterior portion of pubic bone
below urinary bladder