Bone Tissue

Spaces within spongy bone

Red marrow is found within: the large cavities contained within the shafts of long bone. compact bone canals. spaces within spongy bone. all osseous tissue of the appendicular skeleton.

Metaphysis

Region between shaft and end; this is where growth occurs in immature bone

tensile strength

Resistance to tearing and stretching

Example of a flat bone

Scapula

Membrane covering surface of bone

periosteum

hydroxypatite

primary mineral in bone, makes up major portion of bone; gives bone matrix compression strength for weight bearing; tricalcium phosphate

Function of compact bone

protection and support

Spongy bone aka

Cancellous bone, medullary bone

Example of a short bone

Carpals

What must be present before calcification?

Collagen fiber network

What is responsible for tensile strength in bone?

Collagen fibers

Osteocyte processes and ECF inside canaliculi provide network of

Communication & Exchange (oxygen, nutrients, waste products)

Shaft is what type of bone?

Compact

Two types of bone

Compact and spongy

Always covers spongy bone

Compact bone

What does osteoblast do?

Participates in bone formation; secretes matrix: collagen and uncalcified ground substance (osteoid)

Osteoblast becomes

Osteocyte

Principle bone cell

Osteocyte

Types of cells in trabeculae

Osteocytes within lacunae and canaliculi

Inner Periosteum

Osteogenic layer

Lines marrow cavity

endosteum

Osteogenic Cells aka

osteoprogenitor cells

Characteristics of collagenous fibers in bone

Arranged in parallel bundles; layers fit together like plywood, fibers aren't normally naturally visible

What is type of bone tissue based on?

Based on number of spaces in matrix

Mesenchyme

- Embryonic Connective Tissue - Gives rise to all other connective tissues

Parts of a long bone

1) Diaphysis 2) Epiphysis 3) Metaphysis 4) Hyaline 5) Periosteum 6) Marrow cavity 7) Endosteum

Characteristics of bone

1) Forms most of the skeleton 2) Relatively lightweight, considering its strength. 3) Bone is a very dynamic tissue. 4) Continually being remodeled

Five Principle Types of Bones

1) Long 2) Short 3) Flat 4) Irregular 5) Sutural 6) Sesamoid

Composition of Bone

30% collagenous fibers; 50-60% Mineralized salts, <20% Water

Matrix of osseous tissue

50% mineral salts, 35% fibers

When does osteoblast become an osteocyte?

After it is surrounded by matrix

What is Haversian canal surrounded by?

Concentric layers of bone matrix calle lamallae

Compact bone aka

Dense bone; cortical bone

Calcification

Deposition of mineral salts into a framework of collagen fibers

Why isn't a central canal needed in spongy bone?

Diffusion distance isn't very long

Epiphysis

End of a long bone

Example of a long bone

Femur

Outer Periosteum

Fibrous layer

Example of sutural bone

Found in skull (individual variations)

Insterstitial lamellae

Fragments of older, degenerating osteons

What are at ends of branches in compact bone?

Gap junctions

Canaliculi

Hairlike canals that connect lacunae to each other and the central canal; radiate from lacunae; filled with ECF

Funtion of Osseous Tissue

Homeostasis of Important Minerals, Hemopoiesis, Energy storage

Interstitial means

In between

Spongy bone is made up of

Lamellae arranged in an irregular network (lattice)

Components of mineralized salts

Makes bone largely inorganic (50-60%); Hydroxypatite, Calcium carbonate, Magnesium Salts

Periosteum

Membrane that covers bone surface

Endosteum

Membrane that lines the marrow cavity

What are osteoprogenitor cells derived from:

Mesenchyme

What is responsible for compressive strength in bone?

Mineral Salts

Can osteoblasts divide?

No

Does an osteocyte secrete matrix?

No

What do osteocytes direct?

Ongoing activities in mature bone such as protein synthesis and exhange.

Function of spongy bone

Only site of red marrow storage (blood cell formation); arranged to maximize transmission of force)

What does osteoprogenitor cells differentiate into

Osteoblast

Bone cell that Arises from monocytes

Osteoclast

Hyaline

Sometimes called hyaline-like; cartilage, covers bone surfaces where joints form.

What type of bone are the ends in long bone?

Spongy Bone covered with a thin layer of compact

Characteristics of osteogenic cells

Stem cell with mitotic potential

Function of Skeletal System

Support, protection, movement

Why does Osteoprogenitor cells divide?

To maintain stem cell line

Osteoid

Uncalcified ground substance

Example of an Irregular bone

Vertebrae

Cavity of shaft in long bone filled with

Yellow marrow

Marrow Cavity

aka Medulllary Cavity; space within the diaphysis, contains yellow marrow.

Hemopoiesis

blood cell formation

Osteoclast

bone cell that absorbs and removes unwanted bony tissue

osteocyte processes

branches of cell found within canaliculi

Volkmann's canals

channels lying at right angles to the central canal, connecting blood and nerve supply of the periosteum to that of the Haversian canal; also called Perforating ; passageways for vessels and nerves

Lamellae

concentric circles of bone

Osteocyte

mature bone cell

Haversian canal

one of a network of tubes running through compact bone that contains blood vessels and nerves

4 types of cells in bone tissue

osteogenic, osteoblasts, osteocytes, osteoclasts

Diaphysis

shaft of a long bone

Lacunae

small cavities in bone (lamella) that contain osteocytes

Haversian system

structural unit of compact bone; osteons

trabeculae

the irregular latticework of thin bony plates in spongy bone tissue

Spongy bone is composed of

thin plates: trabeculae