Chapters 6-8 short answer/ true-false/ questions

Which injury is more likely to result from playing a contact sport: a dislocated shoulder or a dislocated hip? Why?

Shoulder dislocations occur more frequently than hip dislocations because the shoulder is a more mobile joint. Because the shoulder joint is not bound tightly by ligaments or other structures, it is easier to dislocate when excessive forces are applied. By contrast, the hip joint although mobile, is less easily dislocated because it us stabilized by four heavy ligaments, and the bones fit together snugly in the joint. Additionally, the synovial capsule of the hip joint is larger than that of the shoulder, and its range of motion is decreased.

The last two pairs of ribs are also known as floating ribs.

true

The ligamenta flava connect the laminae of adjacent vertebrae.

true

The nucleus pulposus provides resilience and shock absorption to the intervertebral disc.

true

The patella is a sesmoid bone.

true

Which of the following are examples of irregular bones?

vertebrae

The unpaired facial bones include the?

vomer and mandible

Which of the following pairs of bones make up the bony nasal septum?

vomer and perpendicular plate of ethmoid

Lis the six different types of synovial joints, and give an example of each.

1. Plane joint: sternoclavicular joint; 2. Hinge joint: elbow joint; 3. Pivot joint: proximal radio-ulnar joint; 4. Condylar joint: radiocarpal joints; 5. Saddle joint: first carpometacarpal joint; 6. Ball-and-socket-joint: glenohumeral joint

Distinguish between osteopenia and osteoporosis.

A loss of bone mass as a result of aging is called osteopenia. When the reduction of bone mass is sufficient to compromise normal function, the condition is called osteoporosis.

Describe why epiphyseal fractures are of particular concern.

An epiphyseal fracture is of particular concern because the cartilage can stop growing as it heals. This could result in the fractured limb being shorter than the opposite limb.

Describe the arches of the feet.

Arches assist with transferring the weight of the body to the feet and eventually to the ground. The longitudinal arch runs from the calcaneus to the distal portions of the metatarsals. The transverse arch runs perpendicular to the longitudinal arch. It describes the degree of curvature from the medial border to the lateral border of the foot.

Explain how articular cartilage differs from other cartilage in the body.

Articular cartilage lacks a perichondrium and its matrix contains more water than does the matrix of other cartilage.

Why are impacts perpendicular to the shaft of a long bone more dangerous than stress applied parallel to the long axis bone?

Because the osteons of compact bone run parallel to the long axis of the shaft; impacts perpendicular to the length of the bone are more likely to cause a fracture than stresses parallel to the length of the bone.

What functions do the fontanelles serve during birth?

Fontanelles permit the skull to distort without damage during delivery, helping to ease the infant through the birth canal.

Distinguish between acromegaly and gigantism.

Gigantism is overproduction of growth hormone (GH) before puberty. People with gigantism can be very tall, exceeding 2.7 m (8 ft 11 in.). In acromegaly, GH rises after puberty, so the person does not grow taller, but the bones become thicker.

What is the primary difference between endochondral ossification and intramembranous ossification?

In intramembranous ossification, bone replaces embryonic or fibrous connective tissues. In endochondral ossification, bone replaces a cartilage model.

Describe how a meniscus functions in a joint.

Menisci may subdivide a synovial cavity, channel the flow of synovial fluid, or allow for variations in shapes of articular surfaces to assist with joint stability and cushioning.

Describe how ribs function in breathing.

Movement of the ribs affects the width and depth of the thoracic cage, increasing or decreasing its volume accordingly. This change in volume assists in breathing by increasing and decreasing the pressure inside the thoracic cavity.

Explain why people tend to get shorter with advancing age.

People tend to get shorter with advancing age in part as a result of the decrease in water content of the nucleus pulposus region of intervertebral discs, and in part as a result of a combination of osteopenia and osteoporosis in the vertebrae.

Compare and contrast pituitary growth failure and achondroplasia.

Pituitary growth failure causes reduced epiphyseal cartilage activity and therefore abnormally short bones. Achondroplasia is caused by reduced reduced epiphyseal activity of the long bones, resulting in short, stocky limbs.

Distinguish between the primary and secondary curves of the vertebral coulumn.

Primary curves develop before birth and the secondary curves develop after birth. The thoracic curve and sacral curves are primary curves. The cervical curve is a secondary curve that forms as an infant begins to balance the weight of the head. The lumbar curve is a secondary curve that develops with the ability to stand.

What are the five primary functions of the skeletal system?

Support, storage of minerals and lipids, blood cell production, protection, and leverage

Name the three bones that fuse to form a hip bone. Where do these bones meet?

The three bones that fuse to form the hip bone are the ilium, ischium, and pubis. They meet at the acetabulum.

Which kind of fracture would you expect to occur in a patient whose shinbone broke when her foot stuck to the floor while she was dancing a pirouette?

The twist forces of a pirouette are likely to cause a spiral fracture.

Movement of a limb away from the longitudinal axis of the body is?

abduction

The head of the femur articulates with the pelvis at the?

acetabulum

The hip is an extremely stable joint because it has?

all of the above

The head of the radius is attached to the ulna by the?

annular ligament

Abduction and adduction always refer to movements of the?

appendicular skeleton

Which of the following hormones is involved with blood calcium ion homeostasis and is produced by the kidneys?

calcitriol

The joint between the frontal and parietal bones is correctly called the?

coronal suture

Parathyroid hormone (PTH) is released in response to low blood calcium level.

true

The joints typically located at the end of the adjacent long bones are?

diathroses

The function of articular cartilage is to?

do both a and b

The presence of an epiphyseal line indicates?

epiphyseal growth has ended

Increasing the angle between bones is?

extension

Bone has a rich blood supply but lacks sensory innveration.

false

Both trabecular bone and compact bone have osteons.

false

Standing up from a chair involves hip joint extension and knee joint flexion.

false

The acromioclavicular joint is an example of a condylar joint.

false

The adductor tubercle is a small pit in the center of the head of the femur.

false

The lateral border of the scapula is also called the vertebral border.

false

The ligamentum teres attaches the head of the humerus into the glenoid.

false

The primary ossification centers are localized in the epiphyses.

false

Which of the following is not formed by endochondral ossification?

femur

What is the name of the flexible sheet that interconnects that radius and ulna (and the tibia and fibula)?

interosseous membrane

The formation of bone without a prior cartilage model is?

intramembranous ossification

A dislocation of an articulating surface is?

luxation

Which of the following is not a function of synovial fluid?

maintenance of ionic balance

Bone marrow is located in the?

medullary cavity

Which of the following bones is not part of the orbital complex?

nasal

Which part of the ulna forms the point of the elbow?

olecranon

The external covering of bones, except at the joint cavity, is the?

periosteum

A ballerina standing on her toes is performing which action of the ankle joint?

plantar flexion

Roatation of the radius that makes the palm face posteriorly is?

pronation

Blood cell formation occurs in?

red bone marrow

The synarthrosis formed between the bones of the skull is a?

suture

The joint between adjacent vertebral bodies is a?

symphysis

When you move your head as if to indicate no?

the atlas rotates on the occipital condyles

Although the knee is considered to be only one joint, how many separate joints does it actually have?

three

Which of the following terms is used to describe the structure of spongy bone?

trabeculae

A broken leg that results in a bone piercing the skin is called a compound fracture.

true

A bursa us a synovial fluid pocket outside a joint capsule.

true

A forearm is a small rounded passageway through which blood vessels or nerves penetrate.

true

Appositional growth increases bone diameter.

true

Osteoblastic activity tends to deposit calcium into the bone.

true