Bone Tissues

Skeletal system is made of

bone and cartilage

Functions of the skeletal system (6)

• Providing rigid support framework of the human body

• Allowing movement as muscles pull on bones

• Providing protection for soft internal organs

• Storing minerals in the bone extracellular matrix

• Storing energy in the form of adipose in yellow bone marrow

• Production of blood cells

Bone functions (5)

• Attachment sites for muscles
• Protection of internal organs
• Storage of calcium and other minerals
• Production of blood cells
• Storage of adipose tissue

Cartilage contributes to ___

skeletal system

Is elastic cartilage part of the skeletal system?

No

Where is hyaline cartilage found?

At the ends of bones where they form joints

What is the function of hyaline cartilage at joints?

Helps bones glide past one another.

Loss of hyaline cartilage can lead to what condition?

Osteoarthritis

Where is fibrocartilage found?

Between vertebrae, within the knee, and at the pubic symphysis.

Periosteum

covers the surface of the bone, dense irregular connective tissue lining

Outer shell of compact bone

protects the entire bone

Spongy bone

contains red bone marrow

Medullary cavity

contains yellow bone marrow

Articular cartilage

made of hyaline cartilage found at the joints

Ligaments

attach bones to each other

Classification of bones

• Long bones
• Short bones
• Flat bones
• Irregular bones
• Sesamoid bones

Long bones

longer than they are wide, function as levers

Four examples of long bones

Humerus, femur, ulna, tibia

Epiphysis

end of long bone

Diaphysis

shaft of long bone

Metaphysis

between epiphysis and diaphysis

What important structure is located in the metaphysis?

The epiphyseal plate/line.

Where is the medullary cavity located?

In the diaphysis.

What does the medullary cavity house?

Yellow bone marrow.

Epiphyseal plate (growth plate)

Growing cartilage that allows bones to increase in length (found in children)

What does the epiphyseal plate ossify into in adults?

The epiphyseal line (site of the former plate)

What attaches to the periosteum?

Tendons and ligaments (via perforating fibers).

What vessels are contained in the periosteum?

Blood vessels, nerves, lymphatic vessels.

What role does the periosteum play in growth?

Contains bone-forming cells for growth and repair.

Endosteum structure

Dense irregular connective tissue lining the medullary cavity.

Endosteum function

Contains cells that allow bone growth and remodeling

Short bones

Cube-like, equal length/width/thickness, provide stability and support

Examples of short bones

Carpals (wrist), tarsals (ankle)

Flat bones

Thin, often curved, protect internal organs

Structure of flat bones

Spongy bone layer between two compact bone layers (spongy houses red marrow)

Short bones examples

Skull, sternum, ribs, scapula

Irregular bones

Complex shapes that don’t fit other categories

Examples of irregular bones

Vertebrae, facial bones

Sesamoid bones

Small, round bones embedded in tendons/ligaments, protect tendons from stress

Sesamoid examples

Patella (only universal one). Others may appear in hands/feet

What are the 4 main classes of bone markings?

Articulating surfaces, depressions, projections, holes/spaces

condyle

rounded surface

facet

flat surface

head

prominent round surface

trochlea

pulley-shaped articulating surface

fossa

elongated basin

sulcus

groove

crest

ridge

epicondyle

projection off a condyle

line

slight, elongated ridge

process

prominent feature

ramus

long projection (branch)

spine

sharp process

trochanter

rough round projection

tubercle

small, rounded process

tuberosity

rough surface

canal

passage in bone

fissure

slit through bone

foramen

hole through bone

meatus

opening into canal

sinus

air-filled space in bone

four articulating surfaces

condyle, facet, head, trochlea

nine projections

crest, epicondyle, line, process, ramus, spine, trochanter, tubercle, tuberosity

holes and spaces

canal, fissure, foramen, meatus, sinus