Bone Tissue 2401

What are the matrix rings of compact bone that surround the central canal of each osteon?

Canaliculi

Which is an accurate description of appositional bone growth?

! Osteoblasts build bone at the circumferential lamellae while osteoclasts widen the medullary cavity.

This figure shows the gross anatomy of a long bone. What bone feature does number 4 indicate?

! Osteocyte in lacuna

Which is a sesamoid bone?

! Patella

Rickets, a disease characterized by overproduction and deficient calcification of osteoid tissue, is caused by a lack of sufficient:

! Vitamin D.

Which sex tends to lose more bone mass with aging?

! Women

Which bone forms by intramembranous ossification?

! Zygomatic

The correct chronological order for these steps is

! a - c - d - b

d: Committed cells differentiate into chondroblasts.

! c. - d. - a. - b.

Bone is considered an important storage reservoir for:

! calcium, phosphate, and lipids.

High blood calcium and exercise cause calcitonin release to:

! increase.

Calcidiol circulates in the blood and is converted to calcitriol in the:

! kidney.

Interstitial growth of cartilage increases its ______ and occurs in the _______ region of the cartilage.

! length, internal

To trigger bone growth, growth hormone stimulates the:

! liver to produce somatomedin.

The bones of the fingers and toes (phalanges) are categorized as _____ bones.

! long

As the bone matrix calcifies and the secreting cells become walled in:

! osteoblasts become osteocytes.

Mechanical stress of bones, such as that caused by weight lifting, is detected by:

! osteocytes, which then communicate to osteoblasts to increase synthesis of osteoid.

Flat bones:

! protect underlying soft tissue and may be slightly curved.

What is the function of cartilage located in the epiphyseal plates?

! site of bone elongation and growth

Parathyroid hormone and calcitriol:

! stimulate osteoclasts to resorb bone and release calcium into the blood.

Severe anemia may trigger an adaptive conversion of:

! yellow marrow to red marrow.

This figure illustrates epiphyseal plate morphology. In which zone are minerals deposited in the matrix?

1

This figure illustrates epiphyseal plate morphology. Which is the zone of proliferating cartilage?

1

This figure illustrates the cell types found in bone. Which number indicates an osteocyte?

1

This figure illustrates the cell types found in bone. Which type of cell secretes osteoid?

1

This figure illustrates the components of compact bone. Which number indicates an osteon?

1

This figure shows the anatomy of compact bone. Which number indicates an osteon?

1

This figure shows the gross anatomy of a long bone. Which number is referring to a perforating (or Volkmann's) canal?

1

When during human development does the process of ossification begin?

12 weeks after birth

During bone repair, how long does the stage of the bony callus last?

12-24 hours

This figure illustrates epiphyseal plate morphology. Which zones are considered to be bone tissue?

3, 4, 5

During the process of endochondral ossification, chondrocytes in the cartilage model die. Why does this occur?

Blood supply to the cartilage is cut off by the developing periosteum.

Which hormone inhibits rather than stimulates bone growth?

Calcitonin

Which hormone normally has a more significant effect on blood calcium levels in adults?

Calcitonin

Which is an alternate term for compact bone?

Cancellous bone

This figure illustrates the components of compact bone. Number 5 indicates passageways called

Central canals

What is the thin layer of connective tissue that lines the medullary cavity of a long bone?

Diaphysis

Which region of a growing bone contains the epiphyseal plate?

Distal epiphysis

If a clinician were looking to harvest bone marrow that made blood cells, which bone of a donor would be sampled?

Distal head of femur

Where does hemopoiesis occur?

Epiphyseal line

Which is not involved in the process of bone repair following a fracture?

Fibroblasts produce collagen fibers to connect broken pieces of bone.

Which is characteristic of cartilage connective tissue?

Gel-like ground substance

Which affects osteoblast and osteoclast activity?

Gravity

Which type of cartilage is found in the intervertebral discs?

Hyaline cartilage

What explains the dramatic acceleration in lengthwise bone growth at puberty?

Increased activity of osteoclasts occurs in response to parathyroid hormone stimulation.

What gives bone its flexibility?

Inorganic salts

Which is a change in bone architecture or mass related to aging?

Insufficient calcification

Which is not true about periosteum?

It includes two layers: outer fibrous and inner cellular.

Which is not true about bone remodeling?

It occurs throughout life.

Which is not correct about spongy bone?

Its spaces hold red bone marrow.

This figure illustrates the cell types found in bone. What type of cell does number 3 indicate?

Osteocyte

Which type of cell produces new bone tissue by secreting matrix?

Osteocytes

Before beginning orthodontic treatment, a patient may have her wrist and hand x-rayed to determine her stage of growth. What long bone feature will the orthodontist use to assess this?

Osteon

Which is not a function of bone?

Protection

Consider the classifications of bone, and examples of each. Which classification comprises bones used primarily for movement rather than protection?

Short bones

Which is the definition for a greenstick fracture?

The bone is twisted as it fractures.

If a bone is immersed in a weak acid such as vinegar for several days, its inorganic components will dissolve. What will be the result of such an experiment?

The bone will dissolve completely.

Within which zone of the epiphyseal plate do cartilage cells undergo mitosis?

The zone closest to the medullary cavity

What would be the effect on bone growth of insufficient dietary calcium?

There would be no effect, since the body is able to synthesize calcium.

Which vitamin is required for the normal synthesis of collagen?

Vitamin D

What gives bone its compressional strength?

Yellow bone marrow

Bone is ________ and contains mainly ________ nerves.

avascular, sensory

d: Formation of woven bone and its periosteum

b - a - c - d

The correct order for these zones, beginning with the edge closest to the epiphysis and proceeding toward the diaphysis, is:

c - a - b - e - d

During appositional growth of cartilage, the cells that produce the matrix are the:

chondrocytes.

The type of bone tissue that is replaced more frequently is ________ bone; the part of the femur that is replaced more frequently is the __________.

compact, distal epiphysis

Spongy bone:

contains no osteocytes.

The knobby region of a long bone at the end that is farthest from the trunk is the:

distal diaphysis.

The correct chronological order for these steps is:

f. - b. - c. - d. - a. - e.

The epiphyseal plates in the _________ are the last ones in the body to ossify.

femur

An example of a flat bone would be the:

femur (of thigh).

Glucocorticoids increase bone ________; high levels of serotonin lead to _____ bone density.

formation, high

Parathyroid hormone release is triggered by _______ levels of calcium in the blood.

high

When bone forms by intramembranous ossification, the ossification centers are within:

hyaline cartilage.

In the kidneys, parathyroid hormone acts to ________ production of calcitriol and to ________ excretion of calcium in urine.

increase, increase

Bone growth in which the bone increases in diameter is called:

interstitial growth.

Compact bone:

is located deep to spongy bone in the diaphysis.

The bones of the wrist are classified as _____ bones.

long

Hyaline cartilage contains a ______ percentage of water; cartilage cells reside in small spaces called ________.

low, lacunae

The formation of bone from a cartilaginous model is termed:

mesenchymal ossification.

Endochondral ossification begins with a(n) _________ model.

mesenchyme

Osteoid is the:

organic part of the bone matrix that gives it rigidity.

In compact bone, ___________ connect adjacent lacunae, thereby providing pathways for nutrients and other materials to pass between osteocytes.

osteonic canals

Bone cells called __________ break down bone by secreting hydrochloric acid and enzymes that dissolve the matrix.

osteoprogenitor cells

Calcitonin _________ osteoclast activity and _______ excretion of calcium from the kidney.

stimulates, increases

The break of a bone that has been weakened by disease is a ________fracture; when a broken end of the bone pierces the skin, the fracture is ________.

stress, greenstick.

A fracture parallel to the long axis of the bone is a(n) _________ fracture.

transverse

The periosteum is anchored to the bone by collagen fibers called _____ fibers.

transverse