Chapter 6

Cartilage has a flexible matrix that can accommodate mitosis of chondrocytes.

true

Which type of cartilage is NOT properly matched with its function?

skeletal cartilage; reinforce airways

The pubic symphysis connects the two hip bones anteriorly and provides a little movement during childbirth. Choose the most appropriate tissue for this structure that is subjected to both pressure and stretch.

fibrocartilage

Cartilage grows in two ways, appositional and interstitial. What is appositional growth?

the secretion of new matrix against the external face of existing cartilage

When chondrocytes in lacunae divide and form new matrix, it leads to an expansion of the cartilage tissue from within. This process is called __________.

interstitial growth

Which of the following statements best describes interstitial growth of cartilage?

Chondrocytes in the lacunae divide and secrete matrix, allowing the cartilage to grow from within.

Bones do NOT have a role in __________.

glycogen production

Which of the following is not a function of the skeletal system and bone tissue?

communication

which pairing is NOT correct?

axial skeleton; bones of the limbs

The main role of the axial skeleton is to protect and support vital organs. Is this statement true or false?

True

Bones are classifies by whether they are weight bearing or protective in function.

false

At an archaeological site you discover a bine that is cylindrical in shape, about one Ince long and a quarter of an inch wide. Choose the correct classification.

long

Which of the following pairs is MISMATCHED?

sternum: long bone

Which of the following statements is FALSE?

Long bones include all limb bones except the patella?

The term diploe to the ______.

internal layer of spongy bone in flat bones.

Short, irregular, and flat bones have large marrow cavities in order to keep the weight of the bones light.

False

Flat bones consist of spongy bone sandwiched between compact bone. Is this statement true or false?

True

The trabeculae of spongy bone are oriented toward lines of stress.

true

Yellow bone marrow contains a large percentage of ______.

fat

A fracture in the shaft of a bone would be a break in the _____.

diaphysis

In newborn infants, the medullary cavity and all areas of spongy bone contain yellow bone marrow.

False

Bones are covered and lines by a protective tissue called periosteum. The inner (osteogenic) layer consists primarily of _____.

osteogenic cells

The periosteum is secured to the underlying bone by ______.

perforating (Sharpey's) fibers.

The periosteum is a tissue that serves only to protect the bone because it is not supplied with nerves or blood vessels.

false

Hematopoiesis refers to the formation of blood cells within the red marrow cavities of certain bones.

true

Choose the best location for obtaining a red bone marrow sample from a patient.

hip bone

The cell responsible for secreting the matrix of bone is the _____.

osteoblast.

Osteoblasts _____.

form new bone.

Which description of bone cells is INCORRECT?

Osteogenic cells can differentiate into osteoclasts.

Which of the following cells are NOT matched with its appropriate function?

osteocytes; produce new bone cells.

Bones are constantly undergoing resorption (breaking bone down) for various reasons. Which of the following cells accomplishes this process?

osteoclast

When an osteoblast becomes completely surrounded by its own matrix secretions it is referred to as an ________.

osteocyte

What is the structural unit of compact bone?

the osteon

Which statement is NOT true about the osteon?

The osteon absorbs stress in all directions equally.

There are several components to a functional osteon. Changes to which of the following components would make the bones less strong overall and cause the bones to bend under a person's body weight?

hydroxyapatite

An imbalance that activates these bone cells would lead to a loss of bone density.

osteoclasts

The structure of bone tissue suits the function. Which of the following bone tissues is adapted to support weight and withstand torsion stresses?

compact bone

The central (Haversian) canal that runs through the core of each osteon is the site of ________.

blood vessels and nerve fibers

The structural unit of compact bone (osteon) resembles the growth rings of a tree trunk.

true

Each consecutive bone lamella has collagen fibers that wrap in alternating directions.

true

Choose the structures that most directly provide nutrients and remove wastes from osteocytes in compact bone.

canaliculi

Which of the following is a bone marking name that indicates an armlike bar of bone?

ramus

An osteon contains osteocytes, lamellae, and a central canal, and is found in compact bone only.

true

Which of the following is a site for a muscle or ligament attachment?

trochanter

Choose which bone marking type would likely increase in size when a weight lifter repeatedly exercises muscles that attach to it.

trochanter

The collagen in the osteoid bone matrix makes the overall bone matrix stronger by allowing flexibility. Is this statement true or false?

true

The term osteoid refers to the organic part of the matrix of compact bones.

true

Sixty-five percent of the mass of bone is a compound called hydroxyapatite.

true

Spongy bone contains ________.

trabeculae

Ossification (Osteogenesis) is the process of ________.

bone formation

What is intramembranous ossification

the formation of bone from fibrous membranes

Closure of the epiphyseal plate stops all bone growth.

false

What can a deficiency of growth hormone during bone formation cause?

decreased epiphyseal plate activity

Which structure allows the diaphysis of the bone to increase in length until early childhood?

epiphyseal plate

Ossification of the ends of long bones ________.

is produced by secondary ossification centers

Skeletal remains are discovered at an archeological site. X-rays of the femur show evidence of a thin epiphyseal plate. This bone likely belonged to which of the following?

18 year old male

The process of bones increasing in thickness is known as ________.

appositional growth

Growth of bones is controlled by a symphony of hormones. Which hormone is of greatest importance for bone growth during infancy and childhood?

growth hormone

The hormone that is primarily involved in the control of bone remodeling is calcitonin.

false

Which of the following is the single most important stimulus for epiphyseal plate activity during infancy and childhood?

growth hormone

In some cases the epiphyseal plate of the long bones of children closes too early. What might be the cause?

elevated levels of sex hormones

All bones stop growing by the end of adolescence.

false

What is the weakest part of a developing, adolescent long bone?

the epiphyseal plate

The resilience of bone is thought to come from which of the following?

sacrificial bonds in or between collagen molecules

Which of the following statements is true?

Spongy bone is well adapted to accept stress in many directions, which makes it good for shock absorption.

Osteoid-producing osteoblasts must rely upon this organelle to produce primary structures leading to the formation of collagen and calcium-binding proteins.

ribosomes

At what age do bones reach their peak density?

early adulthood

Which of the following statements is true?

After 21, most people will not experience longitudinal growth of bones.

Compact bone is replaced more often than spongy bone.

false

Which hormone is NOT matched with its appropriate function?

calcitonin; increases blood calcium levels

Which hormone increases osteoclast activity to release more calcium ions into the bloodstream?

parathyroid hormone

Hypercalcemia can be caused by_________.

hypersecretion of parathyroid hormone

In humans, the effect of the hormone calcitonin is to ________.

temporarily decrease blood calcium levels when administered in large doses

Which of the following most directly controls bone remodeling?

mechanical stress and hormones

How can a tooth be moved in a bony socket during orthodontic treatment?

By applying slight pressure to a tooth, the bone on the forward side will reabsorb, while the bone on the reverse side will be reformed.

Which of the following is UNLIKELY to affect bone remodeling?

glucagon

Wolff's law is concerned with ________.

the thickness and shape of a bone being dependent on stresses placed upon it

Which of the following are correctly matched?

compound fracture; the fractured bone ends penetrate the skin

What is the first stage in the healing of a bone fracture?

formation of a hematoma

The correct order (from start to finish) of fracture repair is __________.

hematoma formation, soft callus formation, bony callus formation, and bone remodeling

Which bone would likely take the longest to heal?

thigh bone of an elderly individual

Which of the following refers to a bone disorder found most often in the aged and resulting in the bones becoming porous and light?

Osteoporosis

Prevention of osteoporosis includes adequate intake of ________.

calcium and vitamin D

Select the bone disorder in which bone resorption outpaces bone deposit, leaving the person with thin and often very fragile bones?

Osteoporosis

Which of the following pairings is correct?

paget's disease: excessive and haphazard bone deposition and resorption

Which of the following is implicated in osteoporosis in older women?

estrogen deficiency due to menopause

Remodeling a kitchen to add additional cabinets to existing ones also means adding extra support. In a similar respect, bone remodeling alters bone structure without adversely affecting bone strength. What divalent cation is required to create additional

calcium

Mechanical stress on weight-bearing bones plays a large part in bone remodeling. What single factor plays the largest role in maintaining adequate bone strength?

gravity