Skeletal System

Red marrow

• Situated in cavities of spongy bone and epiphyses of some long bones

• The soft, blood-producing tissue found inside the spongy centers of bones

Yellow marrow

• In the marrow (medullary) cavity

• A type of soft, spongy tissue found inside the hollow center of long bones that mainly stores fat

Osteoblast

Bone forming cells

Osteoclast

Giant bone-destroying cells

Osteocytes

Mature bone cell

Calcium bone growth

Hardens and strengthens your bone matrix

Phosphate bone growth

Combines with calcium to form hydroxyapatite crystals, which give bones their hard structure and strength

Vitamin D bone growth

Helps your body absorb calcium and phosphorus from the food you eat

Cartilage model (hyaline)

A temporary embryonic skeleton made of hyaline cartilage that is gradually replaced by bone tissue during endochondral ossification

Fibrous membranes

Tough sheets of dense connective tissue made of collagen fibers that either cover the outside of a bone or connect parallel bones together

Harvesian Canal

A tiny, hollow channel in the center of an osteon (the main structural unit of compact bone) that runs parallel to the length of the bone

Functions of the skeletal system

Provides a structural framework, protects vital organs, stores essential minerals, and produces blood cells

Intervebral discs

A fibrocartilaginous cushion that sits between adjacent vertebrae in the spinal column

Osteoporosis

A medical condition where bones become thin, weak, and porous, making them break very easily

Pituitary growth hormone

Controls childhood height, tissue maintenance, and body metabolism

Lordosis

The normal inward forward-bending curve of the cervical (neck) and lumbar (lower back) spine

Kyphosis

A spinal disorder that causes an exaggerated forward rounding of the upper back, leading to a hunched or "humpback" appearance

Scoliosis

A medical condition that causes an abnormal sideways curve of the spine, usually shaped like an "S" or a "C"

Bursae

Flattened fibrous sacs 

• Lined with synovial membranes 

• Filled with synovial membranes 

• Not actually part of the joint 

Suture

A rigid, fibrous joint that tightly connects the flat bones of the skull together

Amphiarthroses

Slightly moveable joints 

Synarthroses

Immovable joints

Diarthroses

Freely movable joints

Ball and socket Synovial joint

A type of movable joint where the rounded, ball-like surface of one bone fits into the cup-like depression of another bone

Hinge joint

A type of synovial joint that allows bones to move back and forth in a single plane

Pivot joint

A type of synovial joint that allows only rotational movement around a single axis

Saddle joint

A type of synovial joint where one bone is shaped like a saddle and the other bone fits onto it like a rider on a horse

Arthritis

Inflammatory or degenerative diseases of joints

Gounty arthritis

Inflammation of joints is caused by a deposition of uric acid crystals from the blood

Rheumatoid arthritis

An autoimmune disease- the immune system attacks the joints

Endochondrial Ossification

The biological process where bone tissue is created by first replacing a temporary model made of hyaline cartilage

Simple Fracture

Break that does not penetrate the skin

Compound fracture

Broken bone penetrates through the skin

Greenstick fracture

Bone breaks incompletely

Intramembranous ossification

Direct formation of bone tissue from embryonic connective tissue (mesenchyme) without a prior cartilage model

Epiphyseal disk

A thin layer of hyaline cartilage located between the shaft and the end of a growing long bone

Sprain

A stretching or tearing of ligaments

Dislocation

A painful joint injury where the bones that form a joint are forced out of their normal alignment and position

Hematopoesis

The biological process by which the body creates new blood cells and platelets