Skeletal System: Bones & Joints Flashcards
List the functions of bones:
- form ______ for the entire body
- protect delicate structures, such as the brain and the spinal cord
- work as levers with attached muscles to produce movement
- store ____ salts, which may be resorbed into the blood if needed
- produce blood cells (in the ____)
- a sturdy framework
- calcium
- red marrow
Describe the structure of a long bone:
The long narrow shaft is called the _____
At the center is a ____ cavity, which contains bone marrow.
The long bone also has two irregular ends, a proximal and a distal _____
diaphysis (di-AF-ih-sis)
medullary (MED-u-lar-e)
epiphysis
Name the three different types of cells in bone, and describe the functions of each:
______ build bone tissue.
______ are mature osteoblasts that become trapped in the bone matrix. They maintain bone tissue.
______ are large, multinucleated cells responsible for the process of resorption, which is the breakdown of bone tissue. They develop from a type of white blood cell (monocyte).
Osteoblasts (OS-te-o-blasts)(You can use the mnemonic “Blasts Build” to remember the role of these cells.)
Osteocytes (OS-te-o-sites)
Osteoclasts (OS-te-o-klasts) (You can use the mnemonic “Clasts Cleave.”)
Compact vs. spongy bone:
Compact bone consists of rings of bone cells around a central canal (aka haversian canal) of nerves and blood vessels. Each ring + central canal = one _____. Perforating canals go across the bone.
Spongy bone is made up of a meshwork of small, bony plates of ____ .
osteon
red marrow
Explain how a long bone grows:
Before birth, cartilage starts to ossify into bone. Osteoclasts form the medullar cavity. Secondary bone-forming centers, called _____ develop across the ends of the bones
epiphyseal (ep-ih-FIZ-e-al) plates
Rank three categories of joints based on degree of movement, and give examples of each.
1) Synarthrosis (sin-ar-THRO-sis).
- Not movable
- Usually connected by ______
- Ex: sutures in skull.
2) Amphiarthrosis (am-fe-ar-THRO-sis).
- Slightly moveable
- Usually connected by ____
- Ex: the pubic bones of the pelvis and joints between vertebrae
3) Diarthrosis (di-ar-THRO-sis).
- Freely moveable joints
- Contain a joint cavity, which secretes _____
- Most joints are this type (elbows, knees, fingers)
Synarthrosis –> fibrous tissue
Amphiarthrosis –> cartilage (“cartilaginous joints”)
Diarthrosis –> synovial fluid
Name six types of synovial joints, and give an example of each.
1) ____ : two relatively flat bone surfaces slide over each other with little change in the joint angle
2) ____ : flexion and extension only (ex: elbow joint, joints between phalanges)
3) ____ : rotation only (ex: between atlas and axis)
4) _____ : flexion, extension, abduction, adduction
5) _____ : flexion, extension, abduction, adduction and rotation.
6) . _____—greatest range of motion- circumduction.
Gliding (wrist)
Hinge (elbow)
Pivot (atlas/axis)
Condyloid (knuckles)
Saddle (thumb)
Ball-and-socket (shoulder; hips)
The ____ skeleton includes the bones of the head and torso, and the ____ skeleton includes the bones of the extremities.
axial; appendicular
Yellow marrow is found chiefly in the _____ and is composed mostly of _____
central cavities of the long bones
fat
What are the two kinds of bone membranes?
The ____ is composed of dense irregular connective tissue. This membrane’s inner layer contains osteoblasts that build bone tissue and osteoclasts that break down bone tissue. The coordinated actions of these cells build, repair, and maintain bone throughout life. It contains blood vessels and nerve fibers.
A thinner membrane, the _____, lines the bone’s marrow cavity; it too contains osteoblasts and osteoclasts.
periosteum
endosteum
What are the three steps of fracture repair?
First, reaction, involving hemostasis and an inflammatory response; second, the repair of the damage; and finally, remodeling of new tissue into compact bone (which happens over several years).
Which hormone stimulates osteoclast activity and regulates blood calcium concentration?
parathyroid hormone
Uniting the skull bones is a type of flat, immovable joint known as a ______
suture (SU-chur)
- On one on each side
- Form the prominences of the cheeks
- Each one forms an arch over the cheek with a process of the temporal bone
Zygomatic
- Forms the skull’s posterior portion and a part of its base
- At its base, there is a large opening called the foramen where spinal cord attaches to the brain
Occipital
These two bones contribute to the sides and the base of the skull.
Temporal
These two bones fuse in the midline to form the upper jaw bone, including the anterior part of the hard palate
Maxilla
(pl. maxillae)
These two bones form most of the top and the side walls of the cranium.
Parietal
- The lower jaw bone
- The skull’s only movable bone
Mandible
- Forms the forehead, the anterior of the skull’s roof, and the roof of the eye orbit
- The ___ sinuses communicate with the nasal cavities. These sinuses and others near the nose are described as paranasal sinuses.
Frontal
- Lies at the base of the skull anterior to the temporal bones and forms part of the eye orbit
- It contains the sphenoid sinuses. It also contains a depression called the sella turcica (SEL-ah TUR-sih-ka), literally “Turkish saddle,” that holds and protects the pituitary gland like a saddle.
Sphnenoid
- A light, fragile bone located between the eyes
- Part of the eye orbit, cranial floor, nasal cavity roof
- The superior and middle nasal conchae are part of this bone (KON-ke)
Ethmoid
These two slender bones lie side by side, forming the bridge of the nose
Nasal
These two bones, each about the size of a fingernail, form the anterior medial wall of each orbital cavity.
Lacrimal
When seen from a superior view, it resembles a bat wing
Sphenoid
bony plates that extend into the nasal cavity (superior, middle, inferior)
-superior and middle are part of the ethmoid
nasal conchae (KON-ke)
These paired bones form the posterior part of the hard palate
Palentine
Group of three tiny bones in the ear
Ossicles
Just below the mandible (lower jaw), this U-shaped bone attaches to tongue and other muscles but no other bones
Hyoid
Nasal Septum
The infant’s skull has areas in which the bone formation is incomplete, leaving these membranous “soft spots”
fontanels
In the center of each vertebra is a large hole, the _____
Projecting posteriorly (toward the back) from the bony arch that encircles the spinal cord is the _____, which can be felt just under the skin of the back. Projecting laterally is a _____ on each side. These processes are attachment points for muscles.
Other processes form joints with adjacent vertebrae. A lateral view of the vertebral column shows a series of intervertebral foramina, formed between the vertebrae as they join together.
vertebral foramen
spinous process
transverse process
The first cervical vertebra, called the ____, supports the head.
The second, the _____, serves as a pivot when you turn your head from side to side. It has an upright toothlike part, the dens, that acts pivot point.
The absence of a body in these vertebrae allows for the extra movement. Only the cervical vertebrae have a hole in the transverse process on each side. These ____ accommodate blood vessels and nerves that supply the neck and head.
Atlas
(This vertebra is named for the mythologic character who was able to support the world in his hands.)
Axis
transverse foramina
The thoracic vertebrae, 12 in number (T1 to T12), are located in the chest.
Compared to the cervical vertebrae, they are____ and ____ than the cervical vertebrae and have a longer spinous ___ that points downward.
The posterior ends of the 12 pairs of _____ are attached to the transverse processes of these vertebrae.
larger; stronger
spinous process
ribs
Five separate bones in the child fuse to form this bone in an adult
Wedged between the two hip bones, it forms the posterior part of the bony pelvis.
Sacrum
When viewed from the side, the adult vertebral column shows four curves, corresponding to the four vertebral groups
The ___ and ____ curves remain the two primary concave curves.
thoracic
sacral
Where the manubrium joins the body of the sternum, there is a slight elevation, called the ______, which easily can be felt as a surface landmark.
Sternal Angle
The inferior end of the sternum consists of a small tip that is made of cartilage in youth but becomes bone in the adult
It is used as a landmark for cardiopulmonary resuscitation (CPR) to locate the region for chest compression
Xiphoid Process
The superior portion of the sternum is a roughly triangular bone that joins laterally with each clavicle
Manubrium
These pairs of ribs (8, 9, 10) attach to the cartilage of the rib above
False Ribs
- The first seven pairs of ribs
- Attach directly to the sternum with costal cartilages
True Ribs
The clavicle (KLAV-ih-kl), or collarbone, is a slender bone with two shallow curves. It joins the sternum ____ and the scapula ____ and helps to support the shoulder.
Because it often receives the full force of falls on outstretched arms or of blows to the shoulder, it is the most frequently broken bone.
anteriorly
laterally
Markings of the Scapula
The ____ process connects the scapula to the clavicle.
The ball-and-socket joint of the shoulder has the ___ cavity.
The arm and chest muscles and ligaments attach to the ___ process and to fossae (depressions).
acromion
glenoid
coracoid
When the palm is supine (facing up or forward), the radius and ulna are parallel.
When the palm is prone (facing down or to the rear), the radius crosses over the ulna.
The proximal bone of the upper extremity is the _____ , or arm bone
Tendons attach to the the medial and lateral ____.
The _____ forms a joint with the ulna of the forearm
humerus
epicondyles (ep-ih-KON-diles)
trochlea (TROK-le-ah)
The hip bone, or os coxae, begins its development as three separate bones that later fuse:
1) The ___ forms the upper, flared portion.
2) The ____ is the lowest and strongest part.
3) The ____ forms the anterior part of the os coxae.
ileum
ischium (IS-ke-um)
pubis
Portions of all three pelvic bones contribute to the formation of the ______ , the deep socket that holds the head of the femur (thigh bone) to form the hip joint
acetabulum (as-eh-TAB-u-lum)
What is the largest foramen in the entire body?
obturator (OB-tu-ra-tor) foramen
The female pelvis is adapted for pregnancy and childbirth.
The ___ are wider and more flared.
The ___ and ___ are shorter and less curved.
ilia
sacrum; coccyx
Femur
The large lateral projection near the head of the femur is the _____, used as a surface landmark.
A smaller elevation, the ______ , a is located on the medial side.
On the posterior surface, there is a long central ridge, the _____ (literally “rough line”), which is a point for attachment of hip muscles.
greater trochanter (tro-KAN-ter)
lesser trochanter
linea aspera
The patella is an example of a ______ bone, a type of bone that develops within a tendon or a joint capsule.
sesamoid (SES-ah-moyd)
Leg Bones
Medially (on the great toe side), the ______, or shin bone, is the longer, weight-bearing bone. It has sharp anterior crest that can be felt as the shin bone.
Laterally, the slender ______ does not reach the knee joint; thus, it is not a weight-bearing bone.
tibia
(The Tibia is big like a Tuba.)
fibula
(The Fibula is small like a Flute.)
Foot
There are seven _____ bones associated with the ankle and foot.
The largest of these is the ____ or heel bone.
The ___ above it forms the ankle joint with the tibia.
tarsal
calcaneus
talus
Synovial Joints
Bones in freely movable joints are held together by bands of dense regular connective tissue called_____.
For strength and protection, a ____ ____ of fibrous connective tissue encloses each joint and connects to the periosteum of the bones.
A smooth layer of hyaline cartilage called the _____ _____ protects the bone surfaces in synovial joints.
ligaments
joint capsule
articular cartilage
Near some joints are small sacs called ____, which are filled with synovial fluid.
These lie in areas subject to stress and help ease movement over and around the joints.
bursae (BER-se)
Flexion vs. Extension
_____ is a bending motion that decreases the angle between bones away from the anatomic position.
Ex: closing fingers; raising your hand
___ is a straightening motion that increases the angle between bones and returns the joint toward the anatomic position.
Ex: opening fingers; lowering the raised hand
In ____ , a part is extended beyond its anatomic position.
Ex: moving your leg behind you before you kick a ball
Flexion = decrease angle
Extension = increase angle between bones/return to anatomic
Hyperextension = extend beyond anatomic
______ is movement away from the midline of the body, as in moving the arm straight out to the side.
_______is movement toward the midline of the body, as in bringing the arm back to its original position beside the body.
Abduction
Adduction
Specialized terms describe flexion at the ankle:
_____ bends the foot upward at the ankle, narrowing the angle between the leg and the top of the foot.
_____ bends the foot so that the toes point downward, as in toe dancing.
Dorsiflexion
Plantar flexion (plantar = point)
Specialized terms describe movements of the foot in the lateral plane:
____ is the act of turning the sole inward, so that it faces the opposite foot.
____ turns the sole outward, away from the body.
Inversion
Eversion
Specialized terms describe rotation of the forearm:
____ is the act of turning the palm up or forward.
______ turns the palm down or backward.
Supination
Pronation
Locate the coraoid process, acromion process, and the glenoid cavity (anterior, posterior, lateral view)
Elbow
On the proximal end of the ulna, the ____ process forms the point of the elbow.
The trochlea of the distal humerus fits into the ulna’s deep _____, allowing a hinge action at the elbow joint. This ulnar depression, because of its deep half-moon shape, is also known as the semilunar notch
olecranon (o-LEK-rah-non)
trochlear notch
The medial ____ is a downward projection at the tibia’s distal end; it forms the prominence on the inner aspect of the ankle.
The lateral _____ , at the fibula’s distal end, forms the prominence on the outer aspect of the ankle.
Most people think of these projections as their “ankle bones,” whereas, in truth, they are features of the tibia and fibula.
malleolus (mal-LE-o-lus)
