Bone tissue

What tissues is a bone made up of?

• bone tissue

• marrow

• cartilage

• periosteum

What are the functions of bones?

• support

• protection

• movement

• blood formation

• mineral reservoir

• pH balance

• detoxification

Why does yellow bone marrow sometimes change to red bone marrow?

When the body needs to increase blood cell production.

What does articular cartilage do?

covers the ends of bones where they come together to form joints.

What are the 4 types of cells in bone tissue? What do they do?

• osteogenic cells: stem cells

• osteoblasts: builders

• osteocytes: maintainers

• osteoclasts: breakers

What is bone matrix made of? How does each thing contribute to the strength or flexibility of bone?

collagen=flexibility

minerals=hardness/strength

What is compact bone?

Is the dense, hard outer layer of bone

function: provides strength and support

helps bone resist stress and weight-bearing forces.

Where would you find compact bone?

on the outer, hard exterior layer of all bones

Where is spongy bone located?

inside bones, beneath the compact bone layer

in the ends (epiphyses) of long bones

What is are intramembranous and endochondral ossification? What bones are formed by each?

Explain the steps to each.

Bone forms directly from mesenchyme (connective tissue) without a cartilage model.

Forms:

• flat bones of the skull

• part of the clavicle

What is the epiphyseal plate?

is a layer of hyaline cartilage found near the ends of long bones in children and teens. where bone length growth occurs.

what it is made of epiphyseal plate:?

• hyaline cartilage

• chondrocytes arranged in layers

What factors affect bone growth?

• genetic

• nutritional

• hormonal

• physical factors

What is meant by bone remodeling?

ongoing process where old or damaged bone is broken down and replaced with new bone.

What are the steps in the repair of a fracture?

• hematoma formation

• fibrocartilaginous

• bony (hard) callus formation

• bone remodeling

How does parathyroid hormone ? Why is calcium important?

raises blood calcium by releasing it from bones, increasing kidney retention, and aiding absorption

How calcitonin influence blood calcium levels?

lowers blood calcium by stimulating bone depostition and increasing kidney excretion.

How does exercise affect bone?

by making them build more bone tissue in response to stress.

What happens with demineralization? A decrease in collagen?

• loss of mineral salts (like calcium) from bone. This makes bones weaker, softer, and more likely to fracture.

What happens with decrease in collagen?

Loss of the organic collagen fibers reduces bone’s flexibility and tensile strength, making bones brittle and prone to breaking.

Diaphysis

the shaft (middle part) of a long bone.

Epiphysis

the end part of a long bone.

Metaphyses

is the narrow region of a long bone between the diaphysis (shaft) and the epiphysis (end).

Endosteum

a thin membrane that lines the inner surface of bones.

Periosteum

is a tough, fibrous membrane that covers the outer surface of bones (except at joints).

Articular cartilage

is a smooth layer of hyaline cartilage the covers the ends of bones where they meet to form a joint.

Medullary cavity

is the hollow space inside the diaphysis (shaft) of long bones.

Trabeculae

are the thin, bony struts or beams that form the structure of spongy (cancellous) bone.

Osteon

is the basic structural unit of compact bone.

Osteocyte

is a mature bone cell found inside bone tissue.

Osteoblast

is a bone-building cell.

Osteoclast

is a bone-resorbing (bone-breaking) cell.

Osteoprogenitor

is a stem cell for bone.

Mesenchyme

is a type of embryonic connective tissue made of loosely organized cells in a gel-like ground substance.

Cavitation

is the formation or presence of a space or cavity within a structure or tissue.

Canaliculi

are tiny channels in bone tissue

Lacunae

are small spaces in bone or cartilage tissue.

Haversian canal

is the central channel in an osteon (compact bone unit)

Perforating canal

are channels in compact bone that run perpendicular to the harversian (central) canals.

Periosteum

is a tough, fibrous membrane that covers the outer surface of bones (except at joints).

Endosteum

is a thin membrane that lines the inside of bones.

Appositional growth

is the increase in bone thickness (diameter).

Avascular

means without blood vessels.

Acromegaly

is a condition caused by too much growth hormone i adults

Osteoporosis

is a condition where bones become weak, brittle, and more likely to fracture.

Osteogenesis imperfecta

Is a genetic disorder that causes fragile, easily broken bones.

Fractures

are breaks or cracks in bones.

greenstick

Impacted

Closed

Open

Comminuted

Pott’s

Colles’

Stress