Bones and Bone Tissue

Simple

A _______ fracture is one in which the bone remains aligned and the surrounding tissue is intact.

Greenstick

A ________ fracture is one in which the fracture is imcomplete, similar to when a green stick breaks. This type of fracture typically occurs in young children, mainly because their bones are softer than adult bones, causing the bone to splinter rather than break completely.

Compound

A _______fracture is one in which the bone has peirced the skin. Damage to surrounding tissue, nerves, and blood vessels maybe extensive. Also, because it has broken through the skin, there is an increased risk for infection.

Fracture

A break in a bone is called?

Periosteum

A dense fibrous membrane called the _________ cover the diaphysis. Some of the fibers of the periosteum penetrate the bone, ensuring that the membrane stays firmly ancored. Other fibers of the periosteum weave together with the fibers of tendons. (tendons attach muscle to bone). This arrangement ensures a strong connection between muscle and bone. The periosteum contains bone bone-forming cells as well as blood vessels, making its presence crucial for bone survival.

Short bones

About as broad as they are long, these tend to be shaped like cubes. Examples include the carpel bones of the wrist and the tarsal bones of the ankle.

Excercise

As previously mentioned without adequate physical stress in the form of weight bearing excercise (which includes walking), bone destruction will outpace bone creation.

Long Bones

As the name suggests, these bones have a very long axis and are longer than they are wide. Examples include the femur of the thigh and the humerous of the arm, Long bones work like levers to move limbs.

Physical excercise

Bone adapts to physical stress, its possible to increase bone density through ________ ________. Likewise, a lack of physical excercise causes increased bone loss. This is particulary true in bedridden patients as well as in astronauts experiencing the weightlessness of space.

Resorption, ossification, remodeling

Bone cells work constantly throughtout the life span, destroying old bone _______ and deposting new _______. In this process called _________, osteoclasts remove matrix and reduce the mass of little used bones. In heavily used bones , osteoblasts deposit new bone tissue on the bones surface, thickening the bone. Remodeling repairs minor traumas and contributes to homeostasis by releasing calcium into the blood. This same process also leads to the development of projections and bone surface markings as bone is stimulated by the pull of powerful muscles as children grow and begin to walk.

Torsional Strength

Bone lacks the ability to endure twisting called _______ _______. In fact, most bone fractures result when torsional forces are exerted on an arm or leg.

Epiphyseal plate

Bone legthening occurs at the _______ ______: a layer of hyaline cartilage at the each end of bone. On the epiphyseal side of the cartilage plate , chondrycytes continue to multiply, As these cells move toward the diaphysis, minerals are deposited and the cartilage becomes calcified. As long as chondrocytes are produced in the epiphyseal plate, the bone continues to elongate.

Osseous Tissue

Bone of _______ _______, is a type of connective tissue; like all connective tissues, it consists of cells, fibers, and extracellular material, or matrix. Bone cells include Osteoblasts,

Protect

Bones _______ delicate internal organs, such as the heart, lungs, brain and spinal cord

Acid-base balance

Bones absorb and release alkaline salts to help maintain a stable PH.

Blood production

Bones encase bone marrow, a major site of blood cell formation.

Shape

Bones give the body its structure

Eletrolyte balance

Bones store and release minerals such as calcium and phosphurus- nessaeary ingrediants for a variety chemical reactions throughout the body.

Compressional Strength

Calcium salts allow bones to resist strong sqeezing forces called _______ _______.

Nutrition

Children who are malnourished grow very slowly and may not reach their full height, regaurdless of their genetic potential. Nutrients necessary for proper bone growth include calcium, phosphorus, and vitamins D, C, A.

Tensile strength

Collagen fibers in the matrix make bone highly resistant to stretching forces called _____ ______.

Articular Cartilage

Covering the surface of the epiphysis is a thin layer of hyaline cartilage called ______ _______. This cartilage along with lubricating fluid secreted between bones, eases the movement of the bone within a joint.

Heredity

Every individual inherits a set of genes that determines his maximum height potential.

Comminuted

In a _________fracture, the bone is broken into pieces, This type of fracture is most likely to occur in a car accident.

Spiral

In a ________fracture, the fracture line spirals around the bone, the result of a twisting force. The jagged ends often make this type of fracture difficult to reposition.

Yellow marrow

In adults, most of this marrow has turned yellow, which is rich in fat.

Epiphyseal plate (growth Plate)

In children, a layer of cartilage, called the _______ _____ or ______ _______, seperates the epiphysis from the diaphysis at each end of a long bone. Once growth stops, the plate is replaced by an epiphyseal line.

Red bone marrow

In children, the medullary is filled with blood cell producing ___ ____ _______.

Haversian

In compact bone, layers of matrix are arranged in concentric, onion-like rings called (lamellae) around a central canal called a ________ or osteonic canal. This basic structure unit is called an osteon.

Canaliculi

Microscopic passageways called _______, connect the lamellae to each other.

Endochondral Ossification

Most bones evolve from cartilage. After about three momths' gestation, the fetus has a skeleton composed mostly of cartilage. At that time, the cartiage begins turning into bone. This process which begins in long bones is called ___________ _________.

Irregular Bones

Often clustered in groups, these bones come in various sizes and shapes, Examples include the vertebrae and facial bones. Sesamoid bones are small bones inbedded in tendons, The kneecap is an example of a sesamoid bone.

Bone remoldeling

Replaces about 10% of the skeleton each year.

Intramembranous Ossification

Some bones, including those of the skull and face, start out as fibrous connective tissue. Called ___________ __________ this process begins when groups of stemcells in the tissue differentiate into osteoblasts, Clusters of osteoblasts, called centers for ossification, deposit matrix material and collagen, Eventually, calcium salts are deposited and the bone is calcified.

Spongy Bone

Some osseous tissue is light and porous; this is spongy, or cancellous bone. ______ ______ is found in the long ends of bones and in the middle of most other bones; it is always surrounded by the more durable compact bone.

Epiphyseal Line

Sometimes between the ages of 16 and 25, all the cartilage of the epipseal plate is replaced with spongy bone. When that occurs, bone legthenting stops, and we say that the epiphyses have "closed" What remains is line of spongy bone called _________ _________.

Trabeculae

Spongy, or cancellous bone, consists of a latticework of bone called _______. This design adds strength without adding weight. The cavities between the _______ are filled with red bone marrow. The red bone marrow supplies spongy bones with blood and also produce blood cells.

Support

The bones of the legs, and vertebral column ______ the body and hold it upright

Medullary cavity

The central hollow portion is called the medullary cavity.

Diaphysis

The central shaft -like portion of the bone is called the _______. Thick covered bone makes up this hollow cylinder, giving the bone strength it need to support a large amount of weight.

Epiphysis

The head of each end of a long bone is the _______, The bulbous structure of the epiphysis stregthens the joint; it also an expanded area for attacment of the tendons and ligaments. The epipphysis is made is made of porous-looking spongy bone.

Endosteum

The inside of the medullary cavity is lines with a thin epithelial mebrane call the _________.

osteoclasts, osteoblasts

The maintence of bone density depends upon a balance between the work of _________ (which cause resorption) and ________(which cause ossification). During early and middle adulthood, ossification and resorption are in balance, with the amount of bone being formed equalling the amount of bone being destroyed. During the growth periods of childhood and adolescense, the creation of bone occurs at a faster rate than resorption. After about age 40, bone loss increases while bone formation slows, causing bones to weaken.

Osteology

The study of bone is called ________.

Fact of the ears

The tiniest bone of the body is 3mm long and is found in the ear.

Flat bones

These thin, flat, often curved bones protect organs, such as the bones of the skull, the ribs, and the breastbone (sternum). Others, such as the shoulder blades (scapulae) provide a large surface area for the attachment muscles.

Lacunae

Tiny gaps between rings of the lamellae called ______, contain osteocytes.

Volksmann's canal's

Transverse passageways, called _______ _______. connect the haversian canals. These canals transort blood and nutrients from the bones exterior to the osteocytes locked inside.

Bone Widening and Thicking

Unlike bone lengthening, which stops a certain point, bone _______ and _________ continue throughout the lifespan. A bone widens when osteoblasts in the periosteum lay down new layers of bone around the outside of the bone. As this occurs osteoclasts on the inner bone tissue work to dissolve bone tissue, widening the marrow cavity.

Epiphyseal Fracture

When overstressed, the epiphyseal plate can seperate from the diaphysis or epiphysis, resulting in an __________ ________. When this occurs, future bone growth can be affected.

Compact bone

______ _____ is dense and solid. It's density offers strength witch is why it forms the shafts of long bones and the outer surfaces of other bones.

Compact bone

_______ ______ consists of an elaborate network of canals and passageways containing nerves and blood vessels. The fact that bone cells are so well supplied with oxygen and nutrients allows bone injuries to heal quickly despite the hardness of the bones matrix.

Osteoclasts

________ dissolve unwanted or unhealthy bone.

Trabeculae

_________ are arranged along the lines of greatest stress in a way that offers maximum strength. If the stress a bone is exposed to changes, the ________ will realign themselves to compensate.

Osteoblasts

_________ help form bone by secreting substances that comprise the bones matrix.

Osteomyelitis

_________ is an inflammation of the bone and marrow, usually the reult of a bacterial infection. Bone infections are often difficult tp treat and typically require prolonged intravenous antibiotics.

Movement

_________ of the arms and legs as well as the ability to breathe results from the interaction between muscle and bones.

Hormones

_________ that contribute to proper bone growth include growth hormone, thyroxine, parathroid hormone, insulin and the sex hormones estrogene and testosterone.

Osteocytes

__________ are mature osteoblasts that have become entrapped in the hardened bone matrix. Osteocytes have a dual role: some dissolve bone while others deposit new bone. By doing so, they contribute to the maintenance of bone density while also assisting with the regulation of blood levels of calcium and phosphate.

Osteoporosis

___________, which means "porous bones" is a condition om which bones lose so much mass that they become extremely brittle. Even minor stresses such as bending over or coughing can cause a fracture. Fractures occur most often in the hip, wrist and verebral column.