reading 7 and 8

How many bones does the skeleton typically contain at birth?

270

Which best describes osseous tissue?

A connective tissue with a hardened matrix that makes up bone

What is osteogenesis imperfecta?

A defect in collagen deposition that renders bones exceptionally brittle

Which of the following best describes a medullary cavity?

A hollow cavity within the diaphysis of a long bone

Which describes the structure of a flat bone?

A layer of spongy bone is sandwiched between two layers of compact bone.

Which of the following describes myeloid tissue?

A site of blood cell production

Which of the following describes the zone of cell hypertrophy in an epiphyseal plate?

Chondrocytes in this zone are no longer dividing, but are enlarging; there is a thinning of lacunae walls.

Which osseous tissue is found at the surface of all bones?

Compact

Where do you find osteogenic cells?

Endosteum and periosteum

Another term for a central canal is a(n)___________ canal.

Haversian

What is the name for a channel that extends longitudinally through the center of an osteon?

Haversian canal, central canal

What does the hormone calcitonin do?

Inhibits osteoclasts and stimulates osteoblasts

What is the hollow space in which an osteocyte resides called?

Lacuna

Which of following is a true statement and explains why the number of bones varies with age?

Many bones fuse together during development, resulting in fewer bones in the adult.

Which of the following describes the zone of calcification in an epiphyseal plate?

Minerals are deposited between the columns of lacunae.

What is the term for the connective tissue sheath around the external surface of a bone?

Periosteum

in order for minerals such as calcium and phosphate to be liberated from bone, which process must occur?

Resorption

Which of the following describes the lacunae of osseous tissue?

Spaces between lamellae that contain osteocytes,, Canaliculi are the tiny canals radiating from the lacunae.

The axial skeleton can be defined as which of the following?

The bones of the supporting central axis of the body

What is the metaphysis of a long bone?

Transitional area between diaphysis and epiphysis

In a growth plate, which of the following describes the zone of bone deposition?

Walls between lacunae break down and chondrocytes die. Osteoblasts begin secreting bone matrix.

Which zone of the epiphyseal plate is located the closest to the marrow cavity?

Zone of bone deposition

In which zone of the epiphyseal plate are chondrocytes multiplying and aligning into longitudinal columns of flattened lacunae?

Zone of cell proliferation

What often causes the loss of bone mass seen in osteoporosis in older women?

a loss of estrogen

Where is red bone marrow found in the bones of a child?

almost all bones

A tooth socket is a(n) _______.

alveolus

What are the names of the three cranial fossae?

anterior, middle, posterior

The limb bones and their girdles comprise the ______ skeleton.

appendicular

Which type of bone growth occurs within mature bone and results in the bone becoming thicker?

appositional growth

What is the hyaline cartilage found covering the ends of bones within a joint called?

articular cartilage

The skull, vertebral column, and rib cage comprise the ____________skeleton.

axial

What are the spaces between trabeculae in spongy bone filled with?

bone marrow

Calcitriol acts on which organs to raise blood calcium levels?

bones, kidneys, small intestines

The process in which dense regular connective tissue hardens to form bone is called

calcification

Vitamin D, also known as ______, raises the blood calcium level.

calcitrrol

Which is part of the inorganic matter that makes up the matrix of bone?

calcium phosphate salt

Which two ions are deposited by osteoblasts into the bone matrix?

calcium, phosphate

Name the term for the group of bones that form the roof and walls of the skull.

calvaria

In osseous tissue, the narrow channels connecting neighboring lacunae are called

canaliculi

Bone tissue made up of parallel osteons that are tightly packed together is called________ bone.

compact

Which osseous tissue is found at the surface of all bones?

compact

The layers of bony matrix arranged around the central canal of an osteon are called ______ lamellae.

concentric

Who is likely to have a greater bone density - a construction worker or an office worker?

construction worker

The largest cavity in the skull that encloses the brain is the_____ cavity.

cranial

In longitudinal views, osteons are ______.

cylinders

What are functions of osteocytes

deposit bone, strain sensors, resorb bone

The shaft of a long bone is called the

diaphysis

What is the term for the bone tissue located between the two layers of compact bone in the skull?

diploe

Central and perforating canals are lined with ______.

endosteum

The layer of connective tissue lining internal surfaces of bones is called

endosteum

The structure found between the epiphysis and diaphysis in a child and is a site of bone growth is the______________ plate.

epiphyseal

Where does a long bone grow in length?

epiphyseal plate

What is the expanded end of a long bone to which tendons and ligaments attach called?

epiphysis

Which hormones affect bone growth and development?

estrogen, testosterone, calcitonin, parathyroid hormone

True or false: The bone cells responsible for the formation of the organic bone matrix are called chondrocytes.

false, Chondrocytes produce and maintain the cartilaginous matrix. Osteoblasts are the cells that deposit bone matrix and eventually become osteocytes

True or false: Osteogenic cells are stem cells in the endosteum, periosteum, and central canals that can become chondrocytes.

false, Osteogenic cells are stem cells in the endosteum, periosteum, and central canals that can become osteoblasts rather than chondrocytes.

True or false: Spongy bone is primarily made up of osteons.

false, The matrix is indeed arranged in lamellae like those of compact bone, but there are only a few osteons. Spongy bone mainly consists of trabeculae.

The outer layer of periosteum is a(n) ______.

fibrous layer

What is the term for a slit through a bone?

fissure

What is the function of the osteogenic layer of the periosteum?

growth and healing

Which term refers to a prominent expanded end of a bone that is sometimes rounded?

head

___________cartilage is the tissue which is replaced with bone during endochondral ossification.

hyaline

_________cartilage is the tissue which is replaced with bone during endochondral ossification.

hyaline

Articular surfaces of long bones are covered with which tissue?

hyaline cartilage

Where does bone formation occur during endochondral ossification?

hyaline cartilage model

The calcium-phosphate salt that mineralizes bone tissue is called ______.

hydroxyapatite

Which condition is characterized by excessive excitability of the nervous and muscular systems due to low blood calcium levels?

hypocalcemia

Partial older osteons can be found between complete newer osteons. These partial osteons are referred to as______ lamellae.

interstitial

Which type of bone growth occurs within cartilage and results in bone elongation?

interstitial

In compact bone, what are the remnants of old osteons found between complete osteons called?

interstitial lamellae

The bones of the skull form by which type of ossification?

intramembranous

What bone shape are vertebrae classified as?

irregular

How does calcitriol affect blood phosphate levels?

it raises them

The ______ is an irregular opening for the jugular vein just medial to styloid process.

jugular foramen

What are the layers of bony matrix in compact bone tissue called?

lamellae

Which term refers to a slightly raised, elongated ridge?

line

What shape is the humerus?

long bone

The medullary cavity is also called the ______.

marrow cavity

The infraorbital foramen is in which bone?

maxilla

The transitional area between the shaft and the cartilaginous head of a developing long bone is the

metaphysis

The cribriform foramina of the cribriform plate are passageways for ______.

olfactory nerves

The protein and carbohydrate portion of bone matrix forms the ______ matter.

organic

If you were having joint problems, which medical specialist would be most likely to help you?

orthopedist

During intramembranous ossification, bone matrix is deposited by which type of cells?

osteoblasts

The cells that build new bone and are located in the osteogenic layer of the periosteum are called _____.

osteoblasts

Which bone cells produce the organic bone matrix?

osteoblasts

Bone dissolving cells on bone surfaces are called

osteoclasts

During bone remodeling, the cells that remove unnecessary bone mass are called

osteoclasts

Which bone cells are responsible for bone reabsorption?

osteoclasts

The action carried out by osteoclasts is ______

osteolysis

The basic structural unit of compact bone is the ______.

osteon

A degenerative bone disease characterized by a loss of bone mass and an increased risk of fracture is called

osteoporosis

Which of the following add resonance to the voice and lighten the anterior portion of the skull?

paranasal sinuses

Which gland secretes parathyroid hormone?

parathyroid gland

Which channels run perpendicular to the central canals of osteons?

perforating canals

Cartilage is surrounded by a fibrous layer called a(n)

perichondrium

what surrounds cartilage?

perichondrium

The cerebellum is contained within which cranial fossa?

posterior

In adults, which bone marrow is limited to the axial skeleton, pectoral and pelvic girdles, and proximal heads of the humerus and femur?

red

What is the major producer of blood cells?

red bone marrow

What are two terms associated with myeloid tissue?

red bone marrow, hemopoietic tissue

What is the process of dissolving bone and releasing minerals into the blood called?

resorption

The suture between the parietal bones is the ______ suture.

sagittal

The patella is an example of a ___________ bone, one that forms within a tendon due to stress.

sesamoid

Which type of bone forms within a tendon due to stress?

sesamoid

Bones such as the carpals that have the same length and width are classified as_____________ bones.

short

What bone shape are the carpal bones of the wrist?

short

What are the paranasal sinuses?

sphenoid, ethmoid, frontal, maxillary

The foramen magnum is a hole for the passage of which of the following?

spinal cord

A sharp, slender, or narrow process of a bone is called a ______.

spine

Bone marrow fills the spaces between trabeculae in ______ bone tissue.

spongy

The interior of flat bones is composed of ______ bone.

spongy

_________bone is always enclosed by more durable compact bone.

spongy

Which of the following is a function of yellow bone marrow?

storage of energy

Osteocytes act as __________sensors to adjust bone shape and density to adapt to stress.

strain

Name the term used to describe a groove in which is located a tendon, nerve, or blood vessel.

sulcus

The ______ foramen is a hole that provides passage for a nerve, artery, and vein above the margin of the eye.

supraorbital

Where does the calcium and phosphate used to mineralize bone come from?

the blood

what describes a diaphysis

the shaft of a long bone

What is the purpose of the canaliculi in compact bone?

to provide a passageway between lacunae

Which structures found in spongy bone line up along the bone's lines of stress?

trabeculae

True or false: Compact bone comprises most of the diaphysis of a long bone.

true

Fatty bone marrow that no longer produces blood cells is called

yellow bone marrow

Which zone of the epiphyseal plate is located the farthest from the marrow space?

zone of reserve cartilage