Chapter 6 bone tissue and the skeletal system

Calcification

process that hardens bones by adding calcium phosphate and collagen

Hematopoiesis

production of blood cells

Cartilage (where bones move example rib cage/ joints)

replaced, A semi-ridged form of connective tissues, provides flexibility and smooth surfaces for movement

Repair

to fix

Bipeds

two-legged(humans, kangaroos)

Digitigrade

walking on toes(cats, dogs)

Trabeculae

Lattice-like network of matrix spikes where the lucunae and osteocytes are found from spongy bone, provides strength and balance

Yellow marrow

Long bones, Contains adipose tissue; the triglycerides stored in the adipocytes of the tissue can serve as a source of energy

Lamellar bone

Main type of bone in a mature skeleton characterized by an orderly arrangement of collagen bundles and their cells

Osteocyte

Maintenance cells The primary cell of mature bone and the most common type of bone cell

Endosteum

Medullary cavity has a delicate membraneous lining where bone growth, repair, and remodeling occur

Zone of calcified matrix

Most of the chondrocytes in the zone closest to the diaphysis, are dead because the matrix around them has calcified

Ligaments attach

Muscle to bone

Calcium

Needed to make calcium phosphate and calcium carbonate, which forms the hydroxyapatite crystals that give bone it's hardness

Oblique

Occurs at an angle that is not 90 degrees

Transverse

Occurs straight across the long axis of the bone

Impacted

One fragment is driven into the other, usually as a result of compression

Irregular bones

One that does not have an easily characterized shape (vertebrae that support spinal cord and protect is from compressive forces, facial bones containing sinuses- paranasal sinuses)

Short bones

One that is cube-like in shape, being approximately equal in length, width, and thickness (carpals of the writers and tarsals of the ankles) provide stability and support as well as some limited motion

Meatus

Opening into canal, external auditory meatus

Osteoid

Osteoblasts secrete this, uncalcified matrix, which calcifies (hardens) within a few days as mineral salts are deposited on it, thereby entrapping the osteoblasts within

Canal

Passage in bone, auditory canal

External callus

Periosteal chondrocytes and osteoblasts create this, made of hyaline cartilage and bone, respectively, around the outside of the break (stabilizes the fracture)

Process

Prominence feature, transverse process of vertebrae

Head

Prominent rounded surface, head of femur

Sex hormones

Promote osteoblastic activity and production of bone matrix; responsible for adolescent growth spurt; promote conversion of epiphyseal plate to epiphyseal line

protuberance

Protruding, chin

Omega-3 fatty acids

Reduces inflammation that may interfere with osteoblast function

intramembranous ossification

Replaces membranes in skull, During this compact and spongy bone develops directly from sheets of mesenchymal (undifferentiated) connective tissue. (Flat bones of face, most of the cranial bones, and clavicles)

Open reduction

Requires surgery to expose the fracture and reset the bone

Remodeling

Resorption of old or damaged bone takes place on the same surface where osteoblasts lay new bone to replace that which is resorted (injury, exercise, and other activities lead to this)

Crest

Ridge, illiac crest

Tuberosity

Rough surface, deltoid tuberosity

Condyle

Rounded surface, occipital condyles

Central canal(Haversian canal)

Running down the center of each osteon, which contains blood vessels, nerves, and lymphatic vessels

Comminuted

Several breaks result in many small pieces between two large segments

Spine

Sharp process, ischial spine

Line

Slight, elongated ridge, temporal lines of the parietal bones

Fissure

Slit through bone, auricular fissure

Nutrient foramen

Small openings in the diaphysis

Fovea

Small pit, fovea capitis of the femur

Tubercle

Small, rounded process, tubercle of humerus

Store adipose tissue

Some marrow of long bones is termed "yellow" marrow under normal conditions the function of the yellow marrow is to

Calatriol

Stimulates absorption of calcium and phosphate from digestive tract

Thyroxine

Stimulates bone growth and promotes synthesis of bone matrix

Parathyroid hormone

Stimulates osteoclast proliferation and resorption of bone by osteoclasts; promotes reabsorption of calcium by kidney tubules; indirectly increases calcium absorption by small intestine

Fluoride

Structural component of bone

Magnesium

Structural component of bone

Vitamin k

Supports bone mineralization; may have synergistic effect with vitamin D

Skeletal system

The body system composed of bones and cartilage and performs the following critical functions of the human body (supports the body, facilitates movement, protects internal organs, produces blood cells, stores and releases minerals and fats)

Osteoblast

The bone fell responsible for forming new bone and is found in the growing portions of bone, including the periosteum and the endosteum. Synthesize and secrete the collagen matrix and calcium salts

Zone of maturation and hypertrophy

The chondrocytes are older and larger than those in the proliferative zone

Modeling

The erosion of old bone along the medullary cavity and the deposition of new bone beneath the periosteum not only increase the diameter of the diaphysis but also increase the diameter of the medullary cavity

Fracture

A broken bone

Hypercalcemia

A condition characterized by abnormally high levels of calcium, the nervous system is underactive, which results in lethargy, sluggish reflexes, constipation and loss of appetite, confusion, and in severe cases, coma

Hypocalcemia

A condition characterized by abnormally low levels of calcium, can have an adverse effect on a number of different body systems including circulation, muscles, nerves, and bone

Osteoporosis

A disease characterized by a decrease in bone mass that occurs when the rate of bone resorption exceeds the rate of bone formation, a common occurrence as the body ages

Orthopedist

A doctor who specializes in diagnosing and treating disorders and injuries related to musculoskeletal system

Periosteum

A fibrous membrane that covers the outer surface of the bone. Contains blood vessels, nerves, and lymphatic vessels that nourish compact bone, tendons and ligaments attach to the bone nerve

open or compound fracture

A fracture in which at least one end of the broken bone tears through the skin; carries a high risk of infection

Closed or simple

A fracture in which the skin remains intact

Bone (osseous tissue)

A hard, dense connective tissue that forms most of the adult skeleton, the support structure of the body

Epiphyseal plate (growth plate)

A layer of hyaline (transparent) cartilage in a growing bone, cartilage is eventually replaced by osseous tissue and becomes an epiphyseal line after puberty

Perichondrium

A membrane that covers the cartilage

Greenstick

A partial fracture in which only one side of the bone is broken

Sesamoid bones

A small, round bone that's shaped like a sesame seed (forms in tendons, helps to protect tendons from compressive forces, found in feet, hands, and knees, and the patellae)

Lacuna

A space where every osteocytes is located maintain the mineral concentration of the matrix via the secretion of the enzymes

secondary ossification center

After birth, this same sequence of events (matrix mineralization, death of chondrocytes, invasion of blood vessels from the periosteum, and seeding with Osteogenic cells that become osteoblasts) occurs in the epiphyseal region, and this is what each of these centers of activity is called

Sinus

Air-filled space in bone, nasal sinus

Projection

An area of a bone that projects above the surface of the bone, these are attachment points for tendons and ligaments. In general their size and shape is an indication of the forces exerted through the attachment to the bone

endoskeleton

An internal skeleton(humans)

hole

An opening/groove in the bone that allows blood vessels and nerves to enter the bone, their size and shape reflect the size of the vessels and nerves that penetrate the bone at these points

Invertebrates

Animals without backbones(bugs, jelly fish, microbes)

endochondral ossification

Bone develops by replacing hyaline cartilage(bones at the base of the skull, long bones)

Spiral

Bone segments are pulled apart as a result of a twisting motion

Primary ossification center

By the second/ third month of fetal life, bone cell development and ossification ramps up and creates this, it's a region deep in the periosteal collar where ossification begins

Dipole (spongy bone)

Cancellous bone/ trabecular bone, a very porous type of bone. Highly vascularized and contains red bone marrow. Usually located at the ends of the long bones (epiphyses)

Osteogenic cells

Cell creation, bone repair+growth, Develop into osteoblasts, deep layers of the periosteum and the marrow

Canaliculi

Channels within the bone matrix that nutrients via long cytoplasmic processes that extend through it

Ossification center

Clusters of early osteoblasts

Bone matrix

Collagen and calcium hydroxyapatite are the primary constituents of

Compact bone

Cortical bone, forms the hard external layer of all bones and surrounds the medullary cavity, or bone marrow. It' provides protection and strength to bones. Consists of units called patrons/ Haversian systems

Long bone

Cylindrical in shape, being longer than it is wide(humorous, ulna, radius, femur, tibia, fibula, metacarpals, phalanges, metatarsals, phalanges) they move when muscles contract

Osteon (haversian system)

The microscopic structural unit of compact bone, each osteon is composed of concentric rings of calcified matrix called lamellae

Proliferative zone

The next layer toward the diaphysis and contains stacks of slightly larger chondrocytes

Osteogenic cell

The only bone cells that divide

Reserve zone

The region closest to the epiphyseal end of plate and contains small chondrocytes the matrix, these chondrocytes do not participate in bone growth but secure the epiphyseal plate to the osseuous tissue of the epiphysis

Tendons

The sheaths of tissue that connect bones to muscles

Diaphysis

The tubular shaft that runs between the proximal and distal ends of the bone

Hyaline cartilage

The type of cartilage associated with bone function and development is

Perforating canal(volkmanns canal)

The vessels and nerves of the central canal branch off at a right angle through this, to extend to the periosteum and endosteum

Compact bone

The walls of the diaphysis are composed of this, dense + hard

Epiphysis

The wider section at each end of the bone which is filled with spongy bone, red marrow fills the spaces in the spongy bone

Flat bones

Typically thin and curved(cranial/ skull bones, scapulae/ shoulder blades, sternum/breast bone, and ribs) serve as points of attachment for muscles and protect organs

Fossa

Elongated basin, mandibular fossa

Red marrow

Flat bones, Where hematopoiesis takes place. Red blood cells, white blood cells, and platelets are all produced in the red marrow

Facet

Flat surface, vertebrae

Sulcus

Groove, sigmoid sulcus of the temporal bones

Growth

Grow at the epiphyseal plate

Foramen

Hole through the bone, foramen magnum in the occipital bone

Medullary cavity

Hollow region of the diaphysis, which is filled will yellow marrow

Protection of the brain and soft organs

Important functions of the skeletal system

Both spongy and compact

In which type of bone are osteoblasts and osteoclasts present

Growth hormone

Increases length of long bones, enhances mineralization, and improves bone density

Calatonin

Inhibits osteoclast activity and stimulates calcium uptake by bones

Plantigrade

Walking on the soles of the feet, like a human or a bear.

Unuligrade

Walks on nails/hooves (horses)

Closed reduction

When a broken bone is manipulated and set into its natural position without surgery

Fracture hematoma

When bone is broken, damage to the local vasculature causes hematoma development and triggers initiation of the repair process

Epiphyseal line

When the chondrocytes in the epiphyseal plate cease their proliferation and bone replaces the cartilage, longitudinal growth stops this is what remains of the epiphyseal plate

metaphysis

Where each epiphysis meets the diaphysis and contains the epiphyseal plate

articular cartilage

Where the epiphyses meet other bones to form joints, the epiphyses is covered in this, a thin layer of cartilage that reduces friction and acts as a shock absorber

Articulation

Where two bone surfaces come together, these surfaces tend to conform to one another; such as being rounded and the other cupped to facilitate the function of the articulation

Epiphysis

Which of the following refers to the expanded end of a long bone

Internal callus

Within 48 hours after the fracture, chondrocytes from the endosteum have created this by secreting a fibrocartilaginous matrix between the two ends of the broken bone

Tendon

a band of connective tissue that attaches a muscle to a bone is

Quadrupeds

animals that walk on all fours(dogs, cats)

Vertebrates

animals with backbones(animals, dogs, cats)

Osteoclast

cell responsible for resorbing bone

2 parts of the long bone

diaphysis and epiphysis

exoskeleton

hard protective structure developed outside the body, as the shell of a lobster(crab, lobster, shrimp)

Vitamin d3

needed for calcium absorption