Exam 2: Bone Tissue

short bones,

Small, roughly cuboidal in shape. Ankle, wrist bones, carpals, tarsals...

Inorganic components of bone provide

Strength & Hardness

Function of Dense/Compact bone

Support Protection Movement by contraction Muscle attachment site Mineral Storage (calcium and phosphate) Blood-cell formation (red bone marrow) Energy Metabolism

How is bone able to resist compression and yet remain flexible.

The collagen fibres of bone help it to resist tensile stresses. If the calcium salts of bone were dissolved, then the bone becomes soft & flexibley because of the collagen fibres which are left behind.

trabeculae

The interconnecting supporting bundles (tiny arches) of bone tissue found in spongy bone are called

What is another name for Spongy Bone

Trabecular or cancellous bone In Flat Bones: Diploe

Osteoid

Unmineralized bone matrix composed of proteoglycans, glycoproteins, and collagen

epiphyseal lines

When long bone stops growing, after puberty epiphyseal cartilage disappears and is replaced by this. B

hematopoietic tissue

another term for red bone marrow

myeloid tissue

another term for red bone marrow

ELASTIC CARTILAGE

contains "yellow" elastic fiber networks and collagen fibers. Main protein is elastin. Elastic cartilage is histologically similar to hyaline cartilage but contains many yellow elastic fibers in a solid matrix. Fibers form bundles that appear dark under a microscope. Fibers give elastic cartilage great flexibility so that it is able to withstand repeated bending. Chondrocytes lie between the fibers.

Yellow Bone Marrow

fatty tissue found in the medullary cavity of most adult long bones

Organic Components of bone provide

flexibility and tensile strength of bone.

Red Bone Marrow

found in cancellous (spongy) of long bone; found in diploë (spongy) of flat bones site of hematopoiesis produces red and white blood cells and platelets

Function of Perichondrium

holds cartilage in shape to prevent water loss & growth out of the sides 2 Layers (Outer & Inner)

Interstitial Bone Growth

in contrast with appositional growth, it can occur only when the materials involved are nonrigid, such as cartilage

Circumferential lamella

located deep to periosteum and superficial to endosteum and extend around entire circumference of the diaphysis and resist twisting of long bone

endosteum

membrane lining the medullary cavity of a bone

Hematopoiesis

production and development of blood cells.

Classification of Bones

short bones, long bones, flat bones, irregular bones sesamoid bones

cancellous bone

spongy, porous, bone tissue in the inner part of a bone

FIBROCARTILAGE

"White" Fibrous tissue & cartilaginou. Strongest kind of cartilage, because of it's aternating layers of hyaline cartilage matrix and thick layers of dense collagen fibers oriented in the direction of functional stresses Tends to grade into dense tendon and ligament tissue. Fibrous tissue provide: flexibility and toughness Catilaginous tissue provide: elasticity NO PERICHONDRIUM as it is usually a transitional layer between hyaline cartilage and tendon or ligament.

What percentage of the bones are composed of the organic components

35%

What percentage of the bones are composed of inorganic components

65%

periosteum

A dense fibrous membrane covering the surface of bones (except at their extremities) and serving as an attachment for tendons and muscles.

Type of bone growth that is good for making external features; reshaping

Appositional Growth

What is Hyaline cartilage at the end of bones referred to as?

Articular Cartilage

Where is Hyaline Cartilage Found

Articular surfaces of long bones, the rib tips, the rings of the trachea, and parts of the skull.

OUTER layer of Perichondrium

Binds cartilage to adjacent tissues and provides support and protection

What is unique about bone''s function: energy metabolism?

Bone is an endocrine organ, and affects glucose homeostasis. Yellow Marrow fat located within spongy bony responds to physiologic and pathologic changes in systemic energy metabolism & may acquire function in maintenance energy metabolism in bone.

spongy bone

Bone tissue that consists of an irregular latticework of thin plates of bone called trabeculae and is found just inside the layer of compact bone. Found inside short, flat, and irregular bones and in the epiphyses & medullary cavity of long bones.

Osteoblasts

Bone-forming cells Secrete Osteoid

Bone's organic components

Cells (Osteogenetic, -blasts, -cytes, -clasts) Osteoid (Ground substance & Collagen fibers)

Concentric Lamella

Circular plates of mineralized extracellular matrix of increasing diameter, surrounding a small network of blood vessels, lymphatics, and nerves located in central canal of Osteon

perforating fibers

Collagen fibers that extend from periosteum into bone matrix.

Osteons (Haversian systems)

Concentric layers of ossified (compact) bone matrix (lamella) arranged around a central canal. Contains bone cells, collagen fibers and mineral salts.

Types of Lamella

Concentric, Interstitial & circumferential

Tissues that make up bone

Connective Tissue: osseous, collagen, matrix, blood, dense, irregular, cartilage, bone marrow. Nervous tissue & adipose tissue.

flat bones,

Covering soft body parts. Shoulder blades, ribs, and pelvic bones. Ribs, shoulder blades, pelvis, and skull

This cartilage contains many elastic fibers and is able to tolerate the repeated bending and returning to original shape, resists compression and tension

Elastic

Yellow Cartilage

Elastic Cartilage

Epiphysis

End of a long bone Reigion of Secondary Ossification Center Contains growth plate and has an articular part which forms joints Site of Bone Marrow Storage

This cartilage resists strong compression and strong tension and is unique because it can resist these opposite forces

Fibrocartilage

White Fibrous Cartilage

Fibrocartilage

Where is Fibrocartilage Found?

Forms pubic symphysis, intervertebral discs, menisci, and TMJ.

Where is Elastic Cartilage Found?

Found in the epiglottis and pinnae (external ear flaps)

long bones,

Greater in length than in width and are often slightly curved for the purpose of weight bearing. bones of the arms and legs, phalanges...

Anatomy of: Dense/Compact Bone

Hard, dense bone tissue just deep to Periosteum that contains few spaces between osteons (concentric lamella surrounding a central canal); forms the external portion of all bones and the bulk of the diaphysis (shaft) of long bones. Also called cortical bone.

irregular bones

Have an irregular shape and variable amounts of compact and spongy bone. Bones of the vertebrae and face

This cartilage is the most abundant, provides support and flexibility in the joints and bones

Hyaline

COMPARE & CONTRAST: - HYALINE CARTILAGE - FIBROCARTILAGE - ELASTIC CARTILAGE

Hyaline cartilage - dominant component of extracellular - Collagen matrix with "few" collagen fibers - Has a Perichondrium - Contains: Fibroblasts, Chondroblasts, Chondrocytes, - Bluish-white in life - Translucent / Glassy apperance - important in formation and growth of long bones - Undergoes Calcification in bone formation and also as part of aging process. Elastic cartilage YELLOW - high concentration of ELASTIN fibers - Main Protein is Elastin - Has a Perichondrium - Contains: Fibroblasts, Chondroblasts, Chondrocytes - In extracellular matrix. - Does not calcify - Similar to Hyaline, but contains many Elastic Fibers in a solid matrix. Fibrous cartilage - (fibrocartilage) WHITE - contains large bundles of COLLAGEN fibers. - Chondrocytes in ROWS - No Perichondrium - provide flexibility & strength, resisting compression and shear forces

articular cartilage

Hyaline cartilage attached to articular bone surfaces smooth layer of firm. Makes smooth movement possible and protects bones from rubbing against each other.

What are the three types of cartilage?

Hyaline, Elastic and Fibrocartilage

Type of bone growth that increases overall size.

Interstitial Growth

Interstitial Growth vs. Appositional Growth

Interstitial: Lacunae bound chondrocytes inside the cartilage divide & secrete new matrix, expanding the cartilage (from within.) Appositional: Cells in perichondrium secrete matrix against external face of existing cartilage (from without.)

Interstitial Lamella

Layers inbetween whole osteons of old osteons that broke down as bone grew and remodeled itself

Functions of Spongy Bone

Lightens bone, Arranged in such a way that they can support a lot of force; Oriented in direction of stress; transfers force High surface area, High metabolic activity due to more blood flow, Creates cavities to contain bone marrow

Found within spongy bone of epiphysis

Location of red marrow

Found within Spongy bone of medullary cavity

Location of yellow bone marrow

sesamoid bones

Small round bones found near joints The patella

Osteocyte

Mature bone cells that become fixed in the dense bone matrix, they stop dividing but continue to maintain bone tissue. Relay information to Osteoblasts & Osteoclasts

Bone's inorganic components

Mineral salts, largely calcium phosphates that are present as tiny packed crystals (Hydroxyapatites)

HYALINE CARTILAGE

Most widespread cartilage type, but the weakest. Predominately collagen (yet with few collagen fibers), Has a glassy appearance.

Interstitial Bone Growth

Occurs within INTERNAL regions of cartilage: ZONE of resting cartilage, Proliferations Hypertrophy, Calcification, Bone Deposition 1) Chondrocytes in Lacuna... mitosis 2) 2 Cells in 1 Lacuna... now chondroblasts 3) Chondroblasts make & secrete NEW Cartilage Matrix, which pushes apart...now residing in their own Lacuna...Now Chondrocytes 4) Cartilage Continues to grow in internal reigions as Matrix continues to be produced. new cartilage forms on external face of articular cartilage & epiphyseal plate that faces bone end; at same time old cartilage on internal faces of articular cartilage & epiphyseal plate are destroyed by osteoclasts & replaced with bone by osteoblasts; controlled by growth & sex hormones (ends during adolescence) lengthwise, new cartilage forms at epiphyseal plate, old cartilage destroyed by osteoclasts, replaced by osteoblasts, controlled by sex hormones, ends at adolescence 1) nearest epiphysi 1) larger chondrocytes are arranged in column 1) larger chondrocytes arranged like stacks of coin

Types of bone cells

Osteoblast, Osteocytes, and Osteclasts Help with bone building, maintaining daily activity, and breaking down bone.

Perichondrium

Outer covering of dense irregular connective tissue covering cartilage that develops around the cartilage model during ossification

Bone's influence on the pancrease

Release of insulin

INNER layer of Perichondrium

Secretes the osteoid from basal layer which forms a collar of periosteal bone?

Diaphysis

Shaft of long bone Region of primary ossification Medullary Cavity located with in Site of Bone Marrow Storage

epiphyseal plates

Site of bone growth (both length and girth) composed of cartilage cells that divide and elongate bones Located in between Diaphysis & Epiphysis of long bones A