2 - APP - Unit 2.1 - The Skeletal System Flashcards
Skeletal system
Framework of bones & cartilage (support)
Protects organs
Allows movement
Types of Bones (Classification by shape)
- Long bones
- Short bones
- Flat bones
- Irregular bones
Types of Bones - Long bones
Greater length than width
Expl:
- femur (thigh bone - longest + strongest)
- tibia (medial leg bone / shin bone)
- fibula (lateral leg bone)
- metatarsals (foot bones)
- phalanx (toes or fingers bones)
- humerus (arm bone)
- radius (lateral forearm bone)
- ulna (medial forearm bone)
- metacarpals (hand bones)
- clavicles (collar bones)
Types of Bones - Short bones
Nearly equal length and width (Somewhat cube-shaped)
Expl:
- carpals (wrist bones - 2x8)
- tarsals (ankle bones - 2x7)
Types of Bones - Flat bones
Thin and composed of two nearly parallel plates of bone
Expl:
- cranial (skull bones)
- sternum (breast bone)
- ribs
- scapulas (shoulder blades),
- ilium portion of the coxal bones (hip bone)
Note: coxal bones: ilium (big flat) / pubis (up-front) / ischium (butt bone)
Types of Bones - Irregular bones
Complex shaped
Cannot be grouped into the other three categories
Expl:
- Vertebrae (back)
- Certain facial bones
Types of Bones - Sesamoid bones
Classification by location
Small bones embedded in tendons (connect muscles to bone) where considerable pressure develops
Expl:
- bones within the tendons of muscles leading to the thumb and big toe
- patella (knee cap) - largest sesamoid
Types of Bones - Sesamoid bones - Patella
Kneecaps
Present in everyone
Largest sesamoid bone in the body
Structure of Typical Long Bone - Epiphysis
Enlarged areas on the ends
Structure of Typical Long Bone - Diaphysis
Shaft of the bone between the ends
Structure of Typical Long Bone - Articular cartilage
- Layer of hyaline cartilage that covers the end surface of the bone
- Provides a smooth shock-absorbing surface where two bones meet to form a joint.
Structure of Typical Long Bone - Periosteum
- Fibrous membrane that covers the shaft of the bone.
- Protects the bone + provides attachement for tendons & ligaments.
- Contains abundance of nerves, blood, lymph vessels
Essential to bone nutrition & repair
Structure of Typical Long Bone - Compact bone tissue
- Strong and rigid
- Compose the walls of diaphysis, beneath periosteum
- Forms the hard bone found in shafts of long bones and the plates of bone that surround short, flat & irregular bones
- Protection and support by resisting the stresses placed upon them by the body and gravity
Structure of Typical Long Bone - Spongy bone
- Compose inner portion of the bone
- Irregularly shaped spaces defined by thin, bony plates
- Lightweight but surprisingly strong interior bone structure
Structure of Typical Long Bone - Spongy tissue in flat bones & epiphysis of long bones is filled with…
…red bone marrow. Site of protection for blood cells.
Structure of Typical Long Bone - Medullary cavity
Name of the hollow chamber formed in the shaft of long bones that is field with the red bone marrow.
Medulla = deeper portion Cortex = outer covering
Structure of Typical Long Bone - Marrow
- Connective tissue that fills the spaces inside the spongy bone tissue.
- Function concerned with the formation of red and white blood cells the process of Hematopoiesis
- Aids nutrition of bones
Structure of Typical Long Bone - Marrow - 2 types
- Red marrow
- Yellow marrow
Structure of Typical Long Bone - Red bone marrow
- Functions in the production or red and white blood cells and platelets
- Newborn: Occupies nearly all the bone cavities
- Adult: Found in the bones paces of the skull, ribs, sternum, vertebrae and pelvis
Structure of Typical Long Bone - Yellow bone marrow
Result of inactive blood-producing cells filling with fatty material
Located in various parts of the medullary cavities in long bones
Bone Growth and Development - Capillarities
Highly organized system of blood vessels bringing nourishment to bones
Make their way through the periosteum into the interior of the bones
Bone Growth and Development - Diet
Diet for proper growth and hardening of bony structures: calcium, phosphorous & vitamin D
Vitamin D: important in bone absorption & bone deposition
Bone Growth and Development - Cells responsible for bones growth & maintenance
- Osteoblasts
- Osteoclasts
Bone Growth and Development - Osteoblasts
Cells that built bone tissue
Bone Growth and Development - Osteoclasts
Cells that breakdown and reabsorb bone tissue
Substance liberated by breakdown are recycled by the body and reused to form new bone tissue
Bone Growth and Development - Response to mechanical stress
Within limits, bone can alter its strength, becoming stronger with time through increased deposition of mineral salts and production of collagen fibers
Main mechanical stress: result from the pull of skletal muscles and teh pull of gravity
Expl: Astronauts are subject to weightlessness of space and lose bone mass
Athletes bones are repetitively and highly stressed and become thicker
Bone Growth and Development - Removal of mechanical stress
Weakens bone through demineralization (loss of bone minerals) and reduction in the number of collagen fibers
Functions of Bones - 5 fonctions
- Offer a framework that supports body structures and gives shape to the body
- Protect delicate internal organs and tissues
- Act as levers in conjunction with muscles to produce movement
- Contain the hematopoietic tissues that manufacture blood cells
- Store minerals such as calcium phosphate, calcium carbonate and magnesium
Organization of the Skeleton - 2 skeleton parts
- Axial skeleton
- Appendicular skeleton
Organization of the Skeleton - Axial skeleton - General
Bones of the cranium, inner ear, hyoid, vertebrae and thoracic cage
Organization of the Skeleton - Appendicular skeleton - General
- Bones of the shoulders, upper extremities, hips and lower extremities
- Has more bones than the axial skeleton
- “Appendicular” identifies parts as appendages or extensions of the axis or axial skeleton
Organization of the Skeleton - Quantity of bones
TO BE CONFIRMED
206 names bones: (or 213 ?????)
- 87 Axial skeleton bones
- 126 Axial appendicular bones - Upper extremities
Organization of the Skeleton - Axial Skeleton bones - 6 areas
- Cranium (8)
- Face (14)
- Inner Ear Bones (6) - 3 per ear
- Hyoid bone (1)
- Vertebrae (33)
- Thoracic cage (25)
Organization of the Skeleton - Axial Skeleton bones - Cranium (8)
Forms a protective structure of the brain:
- Frontal (1)
- Parietal (2)
- Occipital (1)
- Temporal (2)
- Sphenoid (1)
- Ethmoid (1)
Organization of the Skeleton - Axial Skeleton bones - Face (14)
Forms the structure of the eyes, nose, cheeks, mouth and jaw
- Maxilla (2)
- Palatine (2) - rear of mouth
- Zygomatic (2) - “cheek” bone (connect to the frontal maxilla & temporal bones)
- Lacrimal (2) - small bones inside eye sockets, produce tears
- Nasal (2)
- Vomer (1)
- Interior nasal concha (2)
- Mandible (1) - “jaw” bone (only movable bone in the face)
Organization of the Skeleton - Axial Skeleton bones - Inner Ear Bones (6)
Forms the internal structure of ears
- Malleus (2) - “hammer”
- Incus (2) - “anvil”
- Stapes (2) - “stirrup”
Organization of the Skeleton - Axial Skeleton bones - Hyoid bone (1)
Supports the tongue
Does not articulate with any other bone
Organization of the Skeleton - Axial Skeleton bones - Vertebrae (33)
Forms the spinal column which supports the head and trunk and protects the spinal cord
- Cervical vertebrae (7) - neck - (C1 + C2 = atlanto axial joint)
- Thoracic vertebrae (12) - upper back
- Lumbar vertebrae (5) - lower back
- Sacral vertebrae - starts out as (5) separate vertebrae - sacrum
- Coccyx - starts out as (4) separate coccygeal vertebrae - tail bone
Organization of the Skeleton - Axial Skeleton bones - Thoracic cage (25)
Forms a protective cage for the lungs and heart. Serves as an attachment for the ribs at the frond of the chest
- Ribs (24)
- Sternum (1) - Breast bone
Organization of the Skeleton - Appendicular Skeleton bones - 2 areas
- Upper Extremities (64)
- Lower Extremities (62)