bio 168 ch 6-8

osteoclasts

resorption of bone

Place the following events in the correct order.

1- Chondroblasts produce a cartilage model that is surrounded by a perichondrium. 2- The perichondrium of the diaphysis becomes the periosteum, and a bony collar is produced. 3- Chondrocytes hypertrophy, die, and calcified cartilage forms. 4- A primary ossification center forms as blood vessels and osteoblasts invade. 5- Osteoblasts lay down bone matrix, forming spongy bone in the primary ossification center. 6- Secondary ossification centers form in the epiphyses of long bones. 7- The cartilage model is almost completely ossified; the remaining cartilage becomes the epiphyseal plate and articular cartilage. 8- The epiphyseal plate becomes the epiphyseal line, and all cartilage (except articular) has become bone.

Put the steps of bone repair in the correct order.

1- Fracture of the bone, damage to blood vessels and surrounding periosteum 2- A localized mass of blood called a hematoma is formed. 3- An internal callus forms between the ends of the bones and an external callus forms a collar around the break. 4- Fibers and cartilage of the calluses are replaced by spongy bone. 5- Woven bone is replaced by compact bone.

Put the following events in the correct order

1- Some mesenchymal cells in the membrane become ostechondral progenitor cells. 2- Osteochondral progenitor cells become osteoblasts. 3- Osteoblasts produce bone matrix that surrounds collagen fibers, and some become osteocytes within the new matrix. 4- Trabeculae develop. 5- Osteoblasts form a ring on the outer surface of the trabeculae. 6- Trabeculae increase in size. 7- Spongy bone forms as trabeculae join together. 8- Red bone marrow appears in the spaces of the spongy bone. 9- Osteoblasts from the periosteum lay down bone matrix to form an outer surface of compact bone.

lace the labels in the numbered boxes so as to accurately reflect the sequence of events of intramembranous ossification.

1- mesenchymal cells become osteochondral progenitor cells 2- osteochondral progenitor cells become osteoblasts. 3- osteoblasts lay down bone matrix around existing collagen fibers 4- osteoblasts become osteocytes as they become surrounded by bony matrix. 5- trabeculae of woven bone and periosteum form 6- woven bone is converted to lamellar bone

rotation

A movement in which a bone spins on its longitudinal axis

circumduction

A movement in which one end of an appendage remains fairly stationary while the other end makes a circular motion

pronation

A movement of the forearm that turns the palm posteriorly or downward is called ________.

flexion

A movement that decreases the angle of a joint anterior to the coronal, or frontal, plane

inversion

A movement that tips the soles medially

supination

A movement that turns the palm to face anteriorly or upward

eversion

A movement that turns the soles laterally

retraction

A posterior movement of a body part in the transverse plane is called ________.

protraction

An example of _________ is sliding the mandible forward.

Place a single word into each sentence to make it correct. Not all terms will be used.

Any break in a bone is called a fracture, and repair is done in stages by the body. A hematoma will form and will turn into granulation tissue at the site of injury. Depositions of collagen and fibrocartilage will form a mass of tissue connecting the broken ends called an internal callus. Cells called osteoblasts deposit a temporary bony collar around the fracture while ossification occurs. The process finishes with bone remodeling, wherein woven bone is replaced by compact bone.

condylar (ellipsoid)

Biaxial joint that exhibits an oval convex surface on one bone that fits into a complementary-shaped depression on the other

saddle

Biaxial joint where both bones are concave in one direction and convex in the other

Outer Perichondrium

Blood vessels and nerves penetrate. No blood vessels in cartilage itself

Select all that are components of the skeletal system.

Bones Cartilage Ligaments Tendons

Ossified bone

Calcified cartilage is replaced by osseous tissue.

How would the urinary system contribute to osteoporosis?

Calcium ions released from the bones are excreted.

PTH

Causes RANKL to be produced Secreted by the parathyroid glands Stimulates an increase in the number of osteoclasts Secreted when blood calcium levels are too low

Zone of proliferation

Chondrocytes divide and form columns resembling stacks of plates or coins

Zone of hypertrophy

Chondrocytes mature and enlarge

A bone fracture that does not perforate the skin is a _________.

Closed fracture

How does the endocrine system affect osteoporosis?

Decreased estrogen levels

Osteoarthritis

Degenerative disorder of joints

Complete each sentence by dragging the proper word or phrase into the appropriate position.

Elongation of bones through endochondral ossification requires the zone of resting cartilage where normal hyaline cartilage persists near the epiphysis. The zone of cell proliferation is marked by an expansive production of chondrocytes that align in rows in order to replenish those undergoing calcification. The next layer is the zone of hypertrophy where the existing, columnar chondrocytes mature and enlarge and thus force the separations between lacunae to become very thin. Hypertrophied chondrocytes lie within a region containing calcified cartilage matrix in the zone of calcification. The osteoblasts lay down new bone matrix by appositional growth.

Bilateral synostosis of the coronal suture:

Expanded posterior cranium and expanded anterior cranium

Rheumatoid arthritis

Inflammation of a joint due to autoimmune condition

Bursitis

Inflammation of fluid-filled sacs associated with a joint

Match the bone matrix component or function with the appropriate classification.

Inorganic material: Provides weight bearing strength and Hydroxyapatite Organic material: Proteoglycans, Provides flexibility, and Collagen

plane (gliding)

Joint in which adjacent bones slide over each other and have relatively limited movement

How does the muscular system affect osteoporosis?

Lack of exercise reduces muscle stress on bone.

How might the integumentary system contribute to osteoporosis?

Lack of exposure to sunlight reduces vitamin D production.

Unilateral synostosis of the left coronal suture:

Lateral expansion of the right cranium

Fill in the blanks with the terms provided. Not all terms will be used.

Mechanical stress occurs in the form of weight-bearing movement and exercise, and it is required for normal bone remodeling. Stress is detected by osteocytes and communicated to osteoblasts. These cells then increase synthesis of osteoid, and this is followed by deposition of mineral salts. Bone strength increases over a period of time in response to mechanical stress.

pivot

Monaxial joint in which a bone spins on its longitudinal axis

Lateral excursion

Moves mandible to either the right or left

ball-and-socket

Multiaxial joint

Synostosis of the metopic suture:

Narrowed forehead and expanded posterior cranium

Zone of resting cartilage

Nearest to the epiphysis; contains randomly arranged chondrocytes that do not divide rapidly

A patient a hospital with a broken femur. A piece of the bone is protruding from the skin, and the femur was shattered into many fragments, none of which line up in their original position. Select all that describe this type of fracture.

Open Displaced Comminuted

Select all that are functions of the skeletal system.

Production of blood cells and platelets Protection of internal organs Storage of minerals

Medial excursion

Returns the mandible to the midline position

calcitonin

Secreted when blood calcium levels are too high Inhibits osteoclast activity Secreted by the thyroid gland

Imagine observing a cross section through the diaphysis of a long bone. Place the following terms in order moving from superficial to deep.

Superficial: Periosteum- compact bone- spongy bone- endosteum- medullary cavity: deep

Patients may exhibit easily fractured bones, especially ______ puberty, a tendency to develop spinal curvature, and ________ joints.

before loose

Sprain

Torn or overstretched tendons or ligaments

True or False? As weight is transferred through the arch system of the foot, some of the ligaments are stretched; when weight is removed from the foot, the ligaments recoil.

True

Which one of the above is most likely to result in strabismus?

Unilateral synostosis of the left coronal suture

Zone of calcification

Very thin zone that contains enlarged chondrocytes and hardening cartilage matrix

A movement of a body part directed away from the midline of the body

abduction

Movement of a body part directed towards the midline of the body

adduction

Drag each label to the appropriate joint it describes. Labels may be used once, more than once, or not at all.

ankle- synovial, hinge toes- synovial, hinge between ankle and toes- synovial, plane

In _______ joints, a rounded bone surface of one bone fits inside a cuplike depression of the other bone.

ball-and-socket

Increased stability of the shoulder

ball-and-socket replaced by hinge

interstitial lamellae

between osteons, remnants of osteons replaced through remodeling

Contained within the spongy sections of bones, marrow is responsible for ________________________.

blood formation

osteons

blood vessel-filled central canal concentric lamellae of bone surround central canal lacunae and canaliculi contain osteocytes and fluid

components of the skeletal system

bone, cartilage, tendons, ligaments

canaliculi

canals occupied by osteocyte cell processes.

osteon or haversian system

central canal, contents, associated concentric lamellae and osteocytes

interstitial

chondrocytes within the tissue divide and add more matrix between the cells

A motion in which one end of an appendage is stationary while the other makes a circular motion is called ________.

circumduction

The most common defect in osteogenesis imperfecta (OI) results from a mutation in the ____________ gene that leads to ______ collagen production.

collagen I less

matrix

collagen fibers for strength, proteoglycans for resiliency

woven bone

collagen fibers randomly orientated. formed: during fetal development and during fracture repair

lamellae

concentric, circumferential, interstitial

Inability to abduct or adduct fingers

condyloid replaced by hinge

articular cartilage

covers bone at joints; has no perichondrium

Place the labels under the category that most likely represents the outcome of the injury described.

decrease active range; passive range unaffected: injury to a nerve controlling a muscle around a joint. increase both passive and active ranges: stretching ligaments on the sides of a joint capsule. decrease both active and passive ranges: pressure from tissue swelling around a joint, and disuse of a joint.

More severe types of OI are due to a ______ in the collagen protein rather than a change in the amount produced.

defect

The combination of continual addition of new bone tissue (bone ____________) and removal of old bone tissue (bone ________________) is called bone ___________. This ongoing process occurs at both the ______________ (outer) and ___________ (inner) surfaces of a bone. Bone replacement is accomplished by the coordination of osteocytes and osteoclasts in a __________________________________ The relative activities of these cells are influenced by two primary factors: hormones and ___________ to the bone.

deposition reabsorption remodeling periosteal endosteal basic multicellular unit mechanical stress

Movement raising a body part in an inferior direction

depression

osteoclasts:

derived from monocytes (which are formed from stem cells in red bone marrow). multinucleated and probably arise from fusion of a number of cells.

perichondrium

double-layered C.T. sheath. Covers cartilage except at articulations.

Minerals can be stored in the skeleton which acts as a reservoir, storing or releasing minerals as needed to maintain _______________ throughout the body.

electrolyte balance

Movement raising a body part in a superior direction

elevation

In _______ joints, an oval-shaped surface of one bone articulates with an oval depression in another bone.

ellipsoid

osteoclasts release

enzymes that digest the bone

A movement that decreases the angle of a joint posterior to the coronal, or frontal, plane

extension

chondroblasts

form matrix

ossification

formation of bone by osteoblasts. osteoblasts communicate through gap functions. cells surround themselves by matrix.

osteoblast

formation of bone through ossification or osteogenesis collagen produced by E.R. and golgi. Released by exocytosis. Precursors of hydroxyapetite stored in vesicles, then released by exocytosis.

Excessive and insufficient growth at the epiphyseal plate lead to _______________ and ____________, respectively.

gigantism dwarfism

Decreased tooth stability and resilience

gomphoses replaced by pivot

A bone fracture generally found in children that is incomplete is a _________.

greenstick fracture

A bone fracture in which the two bone sections do not separate is a _________.

hairline fracture

In _______ joints, a convex cylinder of one bone fits in a concave depression of the other bone.

hinge

Monaxial joint, moving freely in one plane with very little movement in any other

hinge

Knee capable of adduction or abduction

hinge replaced by condyloid

cartilage

hyaline, elastic, fibrocartilage

Extension of a joint beyond its normal range of motion

hyperextension

trabeculae

interconnecting rods or plates of bone. like scaffolding. spaces filled with marrow. covered with endosteum. oriented along stress lines.

osteocytes

mature bone cells.

lamellar bone

mature bone in sheets called lamellae. Fibers are oriented in one direction in each layer, but in different directions in different layers for strength.

stem cells.

mesenchyme (osteochondral progenitor cells) become chondroblasts or osteoblasts.

inner perichondrium

more delicate, has fewer fibers, contains chondroblasts

The ___________ of the entire skeleton or skeletal elements utilizes the anchoring of muscles to attachment sites on the bones which then serve as levers.

movement

appositional growth

new chondrocytes and new matrix at the periphery

osteocytes and nutrients

nutrients diffuse through tiny amounts of liquid surrounding cell and filling lacunae and canaliculi. then can transfer nutrients from one cell to the next through gap junctions.

circumferential lamellae

on the periphery of a bone

bone matrix

organic: collagen and proteoglycans inorganic: hydroxyapatite. CaPO4 crystals if mineral removed, bone is too bendable if collagen removed, bone is too brittle

Martha is short in stature and has had a long history of bone fractures. She has been diagnosed with the most common form of ________________ in which a defect is found in type I ___________ protein.

osteogenesis imperfecta collagen

A Staphylococcal bacterial infection to the bone is one form of ___________.

osteomyelitis.

central or haversian canals

parallel to long axis

Hyaline growth image (top to deepest)

perichondrium appositional growth interstitial growth

perforating or volkmann's canal

perpendicular to long axis. Both perforating and central canals contain blood vessels. Direct flow of nutrients from vessels through cell processes of osteoblasts and from one cell to the next.

In _______ joints, a bony process fits within a bony and/or ligament ring.

pivot

In _______ joints, the articulating surfaces are flat.

plane

A movement of the forearm that turns the palm posteriorly or downward is called ________

pronation

A movement that turns the palm to face posteriorly or downward

pronation

The skull, pelvis, ribs, vertebral column, and sternum provide _________ to many delicate organs of the body by encasing them in hardened shell-like or caged structures.

protection

Collagen is a ________ found in the bone matrix that helps provide ___________ in bones.

protein flexibility

An anterior movement of a body part in the transverse plane is called ________.

protraction

Jutting out the jaw is an example of ________.

protraction

h ions of osteoclasts

pumped across membrane, acid forms, eats away bone.

remodeling bones

removing old bone and adding new woven bone is remodeled into lamellar bone

After several families took up residence on a remote island, they were unable to acquire sufficient levels of vitamin D in their diet. Young children, whose bones were still under development, developed ________ as seen by the noticeable curvature in the long bones of their legs. The adults experienced bone pain between their joints, an outcome consistent with their having developed ___________.

rickets and osteomalacia

A movement in which a bone turns on its longitudinal axis is called ________.

rotation

Turning the head left and right, as in saying "no," is an example of ________.

rotation

A _______ joint consists of a convex surface of one bone articulating with a concave surface of another bone.

saddle

lacunae

spaces occupied by osteocyte cell body

A fracture that takes a helical course around the bone is a _________.

spiral fracture

The bones of the skeleton provide structure to the body and serve as a _________ to hold up the body and maintain proper positioning of some organs.

support

functions of the skeletal system

support, protection, movement, storage, blood cell production

stellate

surrounded by matrix, but can make small amounts of matrix to maintain it.

chondrocytes

surrounded by matrix; are within lacunae

Decrease in nervous system protection

sutures replaced by plane joints

decreased spinal mobility

sympheses replaced by synostoses

Inability to pronate or supinate

synesmoses replaced by synostoses

Unfused os coxa resulting in separated ilia, pubis, and ischia in adulthood

synostoses replaced by synchondroses

Increase in respiratory difficulty

synovial rib attachments replaced by syndesmoses

The medial longitudinal arch prevents the medial side of the foot from touching the ground.

true

Whole body positron emission tomography of a breast cancer patient revealed a cell masses in her left tibia and femur. These were _________ resulting from breast cancer cells destroying and replacing bone tissue.

tumors

ruffled border of osteoclasts

where cell membrane borders bone and resorption is taking place