Bone tissue

The lining of the marrow cavity.

Endosteum

The growth pattern of bone in which matrix is laid down on the surface.

Appositional growth

Bone is ________ and contains mainly ________ nerves.

highly vascularized; sensory

What is the structural unit of compact bone?

the osteon

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

Endosteum

Small channels that radiate through the matrix of bone.

Canaliculi

Where does hemopoiesis occur?

Red bone marrow

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

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

All of the choices are correct.

The cells responsible for the early stages of endochondral ossification.

Chondrocytes

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.

The appearance of this structure signals the end of bone growth.

Epiphyseal line

Area where bone longitudinal growth takes place.

Epiphyseal plate

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

Epiphyseal plate

Smooth, nearly flat articular surface.

Facet

All bones stop growing by the end of adolescence.

False

Bone is considered part of the skeletal system, but ligaments are not.

False

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

False

Compact bone is replaced more often than spongy bone.

False

In adults, an area of compact bone called the epiphyseal tract replaces the epiphyseal plate.

False

Most of the bones of the upper and lower limbs are formed by intramembranous ossification.

False

Once we reach adulthood and our bones are fully formed and hardened, they cannot be remodeled.

False

Osteons run perpendicular to the diaphysis of a long bone.

False

Parathyroid hormone is released by the thyroid gland and causes the small intestine to increase calcium absorption.

False

Since cartilage must be continuously replaced in the body, appositional and interstitial growth of cartilage continues throughout life.

False

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

False

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

False

Round or oval opening through a bone.

Foramen

Which is not a function of bone?

Hormone synthesis

Bone develops from a fibrous membrane.

Intramembranous ossification

Layers of bone matrix.

Lamellae

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

Long bones

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

Os coxa

For intramembranous ossification to take place, which of the following is necessary?

Ossification centers form in the fibrous connective tissue membrane.

Cells that can build bony matrix.

Osteoblasts

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

Osteoblasts

Cells that can dissolve the bony matrix.

Osteoclasts

Bone formed is poorly mineralized and soft. Deforms on weight bearing.

Osteomalacia

Bones are porous and thin but bone composition is normal.

Osteoporosis

Excessive and haphazard bone deposit and resorption.

Paget's disease

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

Parathyroid hormone

Which is a sesamoid bone?

Patella

Armlike bar of bone.

Ramus

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

Site of bone elongation and growth

Sharp, slender, often pointed projection.

Spine

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 become soft and bendable.

Select all that are components of the skeletal system.

The following items chould be checked: Compact bone Trabecular bone Articular cartilage Ligaments

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

The matrix would be softer.

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

The second closest zone to the epiphysis

Very large, blunt, irregularly shaped process.

Trochanter

An osteoclast has a ruffled border and multiple nuclei.

True

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

True

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

True

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

True

Mature cartilage is avascular.

True

Osteoblasts are bone-forming cells; osteoclasts are bone-dissolving cells.

True

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

True

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

True

Which vitamin is required for the normal synthesis of collagen?

Vitamin C

Which sex tends to lose more bone mass with aging?

Women

The process of bone repair includes these steps: a: Fracture hematoma forms b: Bone is remodeled c: Fibrocartilaginous callus forms d: Bony callus forms The correct chronological order for these steps is

a - c - d - b

Bone growth in which the bone increases in diameter is called

appositional growth.

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

blood vessels and nerve fibers

Ossification (Osteogenesis) is the process of ________.

bone formation

Place in correct order the following steps in the process of appositional growth of cartilage. a: New matrix is produced and secreted. b: Chondrocytes differentiate, each in its own lacuna. c: Stem cells undergo mitosis. d: Committed cells differentiate into chondroblasts.

c. - d. - a. - b.

Prevention of osteoporosis includes adequate intake of ________.

calcium and vitamin D

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

canaliculi

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

chondroblasts.

Which of the following is not a function of the skeletal system?

communication

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 zones found in an epiphyseal plate are a: Calcified cartilage b: Hypertrophic cartilage c: Ossification d: Resting cartilage e: Proliferating cartilage The correct order for these zones, beginning with the edge closest to the epiphysis and proceeding toward the diaphysis, is

d - e - b - a - c

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

decreased epiphyseal plate activity

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

distal epiphysis.

The shape of the external ear is maintained by ________.

elastic cartilage

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

The formation of bone from a cartilaginous model is termed

endochondral ossification.

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

epiphyseal plate

The steps in the process of endochondral ossification are a: Ossification center forms in the diaphysis. b: Cartilage calcifies and a bone collar forms. c: Ossification centers form in the epiphyses. d: Bone replaces cartilage. e: Epiphyseal plates ossify. f: Cartilage model develops. The correct chronological order for these steps is

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

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

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

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

high; lacunae

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

hip bone

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

increase; decrease

Lengthwise, long bone growth during infancy and youth is exclusively through ________.

interstitial growth of the epiphyseal plates

Compact bone

is composed of tubular units called osteons.

Ossification of the ends of long bones ________.

is produced by secondary ossification centers

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

length; internal

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

mesenchyme.

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

osteoclast

ones 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

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

osteogenic cells

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

perforating

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

spongy; distal epiphysis

An example of a flat bone would be the

sternum (breast bone).

Wolff's law is concerned with ________.

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

Which bone would likely take the longest to heal?

thigh bone of an elderly individual

Spongy bone contains ________.

trabeculae

Cranial bones develop ________.

within fibrous membranes

Severe anemia may trigger an adaptive conversion of

yellow marrow to red marrow.