Skeletal System

Once a doorknob is grasped with the right hand, what movement of the forearm is necessary to unlatch the door (turn in a clockwise direction)?

D. Supination

Which of these pairs of bones or structures do NOT articulate with each other?

D. head of the ulna - humerus

Explain how a bone grows in diameter and length

Diameter: apposition of new bone matrix on old bone surface beneath the periosteum; Length: cartilage growth at the epiphyseal plate followed by ossification of the cartilage

Which of these is characteristic of a synovial joint?

E. all of the above

Which of these types of joints contain fibrous connective tissue?

E. all of the above

List the three major classes of joints.

Fibrous, cartilaginous, and synovial

List three types of bone cells, depending on their function.

Osteoblasts (makes/builds bone), osteocytes (mature bone cells), and osteoclasts (break down bone cells)

Name the six types of synovial joints and give an example of each

Plane, or gliding joints: articular processes between vertebrae; saddle joints: joint at base of thumb; hinge joints: elbow and knee; pivot joints: between atlas and axis; ball-and-socket joints: shoulder and hip; ellipsoid or condyloid: between occipital condyles and atlas

Which of these is a tunnel-like passage through a bone?

a. canal or meatus

Transverse foramina are found only in

a. cervical vertebrae.

Primary ossification centers of a long bone are found in the

a. diaphysis

As a long bone increases in diameter, the medullary cavity

a. increases in size.

The passageway that carries tears from the eyes to the nasal cavity is

a. the nasolacrimal canal.

Head of the femur

acetabulum

The __ is the socket of the hip joint, and the __ is the large hole in the coxa.

acetabulum, obturator foramen

Projection from the scapular spine that forms the point of the shoulder; point of attachment of the clavicle.

acromion process

Cartilage that provides a smooth surface where bones meet

articular cartilage

Where vertebrae articulate with each other

articular process

First cervical vertebra; allows a "yes" motion of the head.

atlas

The prime function of osteoclasts is to

b. break down bone.

Intramembranous ossification

b. gives rise to the flat bones of the skull.

Usually no __ penetrate the trabeculae, and the trabeculae have no central canals

blood vessels

Within the central canal are __ that run parallel to the long axis of the bone

blood vessels

Middle part of the sternum.

body

Weight-bearing portion of the vertebra

body

Extracellular matrix is made up of collagen and minerals.

bone

Extension of the synovial membrane that forms a pocket or sac; reduces friction where structures would rub together.

bursa

The weight-bearing portion of a vertebra is the

c. body.

Which of these is part of the appendicular skeleton?

c. clavicle

A break in the shaft of a bone is a break in the

c. diaphysis.

The squamous suture joins the

c. parietal and temporal bones

Which of these bones does NOT contain a paranasal sinus?

c. temporal

Which of these parts of the upper limb is NOT correctly matched with the number of bones in that part?

c. wrist: 10

Inferior to the talus; protrudes posteriorly to form the heel.

calcaneus

The chondrocytes of the cartilage model increase in number, hypertrophy, and die and the cartilage matrix becomes __ , forming an ossification center

calcified

Bone is the major storage site for __ in the body.

calcium

The zone of tissue repair between the two bone fragments is called a __ .

callus

Tunnel-like passage through a bone.

canal or meatus

Cell processes extend from the osteocytes across the extracellular matrix of the lamellae within tiny canals called __.

canaliculi

Nutrients pass by diffusion through the __ to the osteocytes of the trabeculae.

canaliculi

The osteocytes are connected to each other by cell processes located in __.

canaliculi

Osteoblasts enter the callus and begin forming __ bone, which is later remodeled.

cancellous

Projection from the scapula that curves below the clavicle and provides attachment for arm and chest muscles.

caracoid process

Give the number of carpals, metacarpals, and phalanges in the upper limb, and give the number of tarsals, metatarsals, and phalanges in the lower limb.

carpals: 8, metacarpals: 5, phalanges: 14, tarsals: 7, metatarsals: 5, phalanges: 14

Extracellular matrix is made up of collagen and proteoglycans.

cartilage

Endochondral ossification begins with a __ , which has the general shape of the mature bone.

cartilage model

Two bones united by cartilage; only slight movement can occur at these joints

cartilaginous

Most of the lamellae of compact bone are organized into sets of concentric rings with each set surrounding a __.

central canal

There are seven of these vertebrae in the vertebral column.

cervical

Have transverse foramina and partly split spinous processes.

cervical vertebrae

Name the five types of vertebrae, and give the number of each found in the vertebral column.

cervical: 7, thoracic: 12, lumbar: 5, sacrum: 1, coccyx: 1

Just as in endochondral ossification, __ increase in number.

chondrocytes

When a bone is broken, the bone bleeds, and a __ is formed in the damaged area.

clot

Tailbone, usually consisting of four fused vertebrae.

coccyx

List two types of bone, depending on their internal structure

compact: hard outer layer cancellous: lacey networks

Smooth, rounded end of a bone, where it forms a joint with another bone.

condyle

Proximal end of tibia

condyles of femur

Intramembranous ossification occurs when osteoblasts begin to produce bone in ossification centers of __ membranes.

connective tissue

Each __ is formed by the fusion of the ilium, ischium, and pubis.

coxa

Subdivision of the skull that protects the brain.

cranial vault (braincase)

Which of these connective tissue structures cover the surface of mature bones?

d. b and c

In compact bone, the osteocytes are connected to each other by tiny cell processes extending through tiny canals called

d. canaliculi.

During bone growth at the epiphyseal plate, _____ increase in number, hypertrophy, and die.

d. chondrocytes.

Process that forms the outer ankle?

d. lateral malleolus

The perpendicular plate of the ethmoid and the ______ form the nasal septum.

d. vomer

Calcium is removed from bones when blood calcium levels __ , and it is deposited when dietary calcium is adequate.

decrease

As osteoblasts deposit new bone matrix on the surface of bones between the periosteum and the existing bone, the bone increases in __.

diameter

Each long bone consists of a shaft, called the __ , and a(n) __ at each end of the bone.

diaphysis, epiphysis

Semilunar notch

distal end of humerus

In the healing of bone fractures

e. all of the above

Which of these is a function of bone?

e. all of the above

Bone matrix contains

e. both a and b

Ossification process that produces most of the skeletal system

endochondral ossification

The medullary cavity is lined with a thinner connective tissue membrane, the __ .

endosteum

Location where forearm muscles attach to the humerus

epicondyles

Projections lateral to the condyles on the distal end of femur.

epicondyles

When bone growth stops, the epiphyseal plate is replaced by bone, and is called the __.

epiphyseal line

A long bone that is still growing has a(n) __ , composed of cartilage, between each epiphysis and the diaphysis

epiphyseal plate

Temporal bone canal; allows sound to reach the eardrum

external auditory meatus

Bones that form the structure of the face, but do not contribute to the cranial vault.

facial bones

Yellow marrow consists mostly of __ , whereas red marrow consists of __ cells

fat, blood-forming

The pelvic inlet and outlet are larger and the pelvic inlet is more oval in the pelvis of the __.

female

Two bones united by fibrous tissue; exhibit little or no movement.

fibrous

Bones such as the ribs, scapula, and sternum

flat bones

Eleventh and twelfth ribs, which have no attachment to the sternum

floating ribs

Wide sutures (soft spots) present in newborns.

fontanels

Hole in a bone

foramen

Opening through which the spinal cord connects to the brain.

foramen magnum

Depression in a bone

fossa

Depression where the head of the humerus articulates with the scapula.

glenoid fossa

Fibrous joints consisting of pegs fitted into sockets

gomphoses

Location for shoulder muscles to attach to the humerus.

greater and lesser tubercles

Glenoid fossa

head of humerus

Humerus and ulna

head of radius

Carpals

head of ulna

Bone that "floats" in the neck and is the attachment site for throat and tongue muscles.

hyoid bones

The superior margin of the ilium is called the __ , and a(n) __ is located at each ilium's anterior end.

iliac crest, anterior superior iliac spine

Dense fibrous connective tissue that separates vertebrae.

intervertebral disk

Where the spinal nerves exit the vertebral column

intervertebral formina

Name two types of bone ossification.

intramembraneous, endochondral

Bone formation that occurs within connective tissue membranes

intramembranous ossification

Ossification process that occurs primarily in the flat bones of the skull.

intramembranous ossification

Bones such as the vertebrae and facial bones.

irregular bones

Surrounds the joint cavity; portions may be thickened to form ligaments.

joint capsule

The space surrounding the ends of articulating bones

joint cavity

Depression at the superior end of the sternum

jugular notch

The osteocytes are located within spaces called __.

lacunae

Bone is formed in thin sheets of extracellular matrix called __ , with bone cells, called __ between the lamellae.

lamellae, osteocytes

Two parts that form the vertebral arch.

lamina, pedicle

Growth in the __ of a bone, which is the major source of increased height in an individual, occurs in the __ .

length, epiphyseal plate

Extracellular matrix is made up primarily of collagen.

ligaments, tendons

Bones longer than they are wide, e.g., limb bones.

long bones

Superior articular facets of these vertebrae face medially and "lock" with laterally facing inferior articular facets of the vertebra above it.

lumbar

There are five of these vertebrae in the vertebral column.

lumbar

Prominence on each side of the ankle that forms a partial socket for the talus bone.

malleolus

Depression where mandible articulates with temporal bone.

mandibular fossa

Most superior part of the sternum

manubrium

The spaces between the trabeculae are filled with __.

marrow

This space, and other spaces are filled with soft tissue called ___.

marrow

The large cavity in the diaphysis is called the __.

medullary cavity

List three functions of cartilage

model for bone growth, smooth joint surfaces, and support

Three bony shelves of the nasal cavity that help to warm and moisten the air.

nasal conchae

Perpendicular bone and cartilage that divide the nasal cavity into right and left halves.

nasal septum

Opening that passes from the orbit into the nasal cavity

nasolacrimal canal

Opening through which the optic nerve passes into the skull.

optic foramen

Cone-shaped fossa that surrounds the eye.

orbit

Structure in the skull that surrounds and protects the eye.

orbit

Large openings through which nerves or blood vessels communicate with the eye.

orbital fissures

This process produces a zone of __ on the diaphyseal side of the epiphyseal plate.

ossification

The periosteum and endosteum contain __ , which function in the formation, repair, and remodeling of bone.

osteoblasts

When chondrocytes die, __ invade spaces in the center of the bone and produce bone matrix; __ remove bone and calcified cartilage to form the medullary cavity.

osteoblasts, osteoclasts

The cartilage matrix is __ , and __ start forming bone matrix on the surface of the calcified cartilage.

osteoblasts, osteocytes

Bone remodeling involves the removal of old bone by __ , and the deposition of new bone by __ .

osteoclasts, osteoblasts

Each trabecula consists of several lamellae, with __ between the lamellae.

osteocytes

Each central canal with the lamellae and osteocytes surrounding it, is called a(n) __.

osteon

Two parts that form the hard palate

palatine process of maxilla, horizontal plate of palatine

Air-filled cavities that open into the nasal cavity.

paranasal sinuses

Located within the major tendon of the thigh muscles; enables the tendon to turn the corner over the knee.

patella

Name the bones of the pectoral and pelvic girdles.

pectoral: clavicle & scapula, pelvic: sacrum & coxa

Most of the outer surface of the bone is covered by a connective tissue layer called the __ , which contains blood vessels and nerves.

periosteum

Blood vessels in the __ supply blood to vessels in the central canal

periosteum & endosteum

The center part of the diaphysis where bone first begins to appear is called the __.

primary ossification center

Projection from a bone

process

Within the __ zone, the chondrocytes line up in columns, hypertrophy, and die

proliferating

Location of attachment of the biceps brachii to the radius.

radial tuberosity

Five fused vertebrae that have a median crest and a hiatus

sacrum

Later, __ form in the epiphyses.

secondary ossification centers

Structure resembling a saddle that is occupied by the pituitary gland.

sella turcica

Bones as broad as they are long, e.g., ankle and wrist bones

short bones

Ridge that runs across the posterior surface of the scapula.

spine

Lumps that can be seen and felt down the midline of the back.

spinous process

Slight elevation at the junction of the manubrium and body of the sternum; landmark for locating the second rib.

sternal angle

Attachments for the ligaments of the wrists.

styloid process

List five functions of bone.

support, protection, lever system, mineral storage, blood cell formation

Fibrous joints between the bones of the skull.

sutures

Fibrous joints where bones are separated by some distance and are held together by ligaments

syndesmoses

Freely moving joints that contain fluid in a cavity surrounding the ends of bones

synovial

Tissue that lines the joint capsule except over the articular cartilage; produces synovial fluid.

synovial membrane

Distal end of tibia and fibula.

talus

Two bones that form the zygomatic arch.

temporal, zygomatic

Attach muscles to bones

tendons

There are twelve of these vertebrae in the vertebral column.

thoracic

Articular facets for ribs present.

thoracic vertebrae

Two sections of the vertebral column that curve posteriorly.

thoracic, sacral

Head of fibula.

tibia

Location on the tibia where anterior thigh muscles attach.

tibial tuberosity

Cancellous (spongy) bone consists of delicate interconnecting rods or plates of bone called __.

trabeculae

Points of muscle attachment near the head of the femur

trochanters

First seven pairs of ribs that attach directly to the sternum

true ribs

Name the three types of ribs according to their attachment, and give the number of each type.

true ribs: 1-7, false ribs: 8-10, floating ribs: 11-12

Lump on a bone.

tuberosity

Contains the spinal cord; all of them together form the vertebral canal.

vertebral foramen

Two parts that form the nasal septum.

vomer, perpendicular plate of ethmoid