SKELETAL SYSTEM
ANATOMY & PHYSIOLOGY
Mr. Eric Mahinay| 1St Semester | BSN – 1B
S.Y. 2023 – 2024
• 206 bones 4) IRREGULAR BONES
• Interconnect system of bones, ligaments & • Bones that don’t
tendons fit to other
• Composed of 50% water & 50% osseous categories due to
tissue irregular shapes
• Include: vertebrae,
FUNCTIONS pelvic, hyoid
1) Support, shape & framework of the body
2) Protect internal organs 5) SESAMOID (Round) BONES
3) Storage place for minerals • Small & round
4) Hematopoiesis – production of RBC in bone • Embedded w/in tendons
marrow adjacent to joints
5) Place to attach muscles • e.g., patella (kneecap)
6) Movement possible through articulation
TYPES OF BONES BONE FORMATION
• Begins as cartilage
1) LONG BONES • Calcifies in utero
• Found in limbs • At birth, fontanels remain
• Made up of a body OSSIFICATION
(diaphysis) & 2 extremities • Bone production process gives bone extreme
(epiphysis) tensile & compressional strength
• Wall consists of dense • Strength
tissue contributor:
• Central/Medullary canal
is filled w/ marrow
Factors contributing BONE GROWTH
2) SHORT BONES 1) Nutrition – calcium consumption; increase
• Found where strength, compactness, & blood calcium triggers release of calcitonin;
limited movement are desired decrease of calcium release Parathyroid
• Includes: Tarsals & Carpals hormone
2) Exposure to Sunlight – UVL on skin cause VitD
production; promotes proper absorption of
calcium
3) Hormonal Secretion – Human growth hormone,
Somatotropin = stimulate activity in epiphyseal
plate
4) Physical Activity – Increase physical exertion =
increase bone density & strength
3) FLAT BONES Bone Maintenance
• Main locations: Skull, scapula & sternum • Osteoblast - Formation of new bone
• Used in spots where protection / muscular • Osteoclast – Destruction / destroy of bone
attachment is desired • Osteocytes – Primary Cell
• Osteogenic – Origin of Cell
Divisions of the Skeletal System
2 main division:
AXIAL SKELETON
APPENDICULAR SKELETON
TRANS BY: IOLA PRINCESS AMADO 1
, SKELETAL SYSTEM
ANATOMY & PHYSIOLOGY
Mr. Eric Mahinay| 1St Semester | BSN – 1B
S.Y. 2023 – 2024
• Inferior conchae – thin curved bones which
project from interior of nasal cavity
AXIAL SKELETON
• Central skeleton that protects & supports vital
organs (brain, heart, lungs)
• Composed of skull & vertebrae
• Mainly flat &
irregular bones
• Support body
along central axis
PARTS OF AXIAL SKELETON
Intervertebral Discs
• Skull – protects brain
• Pads of cartilage between each vertebrae
• Vertebrae – protect spinal cord; keep skeleton
• Cushioning = reduce shock
upright
• High water content
• Ribs – protect lungs & heart; hard surface for
• Aging lowers water
intercostal muscles to move against for
content; drying
breathing
discs
SKULL Division • Herniated (slipped)
• Cranium – 8 bones which hold & protect brain disc – disc
• Facial bones – 14 bones that make up the face; protrudes from
2 are paired spine
Cranium
• Frontal bone – forehead, eyebrows, & superior
section of eye orbital
• Parietal Bone – form most of the superior & Bony Thorax
lateral walls of cranium • Bones connect & protect heart & lungs
• Temporal Bones – inferior to parietal bones • Ribs, Costal Cartilage, & Sternum
• Occipital bone – back & floor of cranium;
foramen magnum (large hole) allows spinal cord RIBS
to meet brain • 12 pairs, each connect to a thoracic
vertebrae
• First 7 pairs = true ribs; attached directly to
sternum
• Last 5 pairs = false ribs; no attachment; last 2
are floating (no sternal attachment)
Facial Bones
• Mandible – lower jawbone
• Maxillary bones (maxillae) fuse to form upper
jaw
• Palatine processes – posterior to maxillae;
forms rear of hard palate
• Zygomatic bones – cheekbones
• Lacrimal bones – inferior of orbital bones;
passageway for tears
• Ethmoid bone – roof of nasal cavity
• Nasal bones – bridge of nose
• Vomer – divides nasal cavity in half
TRANS BY: IOLA PRINCESS AMADO 2
ANATOMY & PHYSIOLOGY
Mr. Eric Mahinay| 1St Semester | BSN – 1B
S.Y. 2023 – 2024
• 206 bones 4) IRREGULAR BONES
• Interconnect system of bones, ligaments & • Bones that don’t
tendons fit to other
• Composed of 50% water & 50% osseous categories due to
tissue irregular shapes
• Include: vertebrae,
FUNCTIONS pelvic, hyoid
1) Support, shape & framework of the body
2) Protect internal organs 5) SESAMOID (Round) BONES
3) Storage place for minerals • Small & round
4) Hematopoiesis – production of RBC in bone • Embedded w/in tendons
marrow adjacent to joints
5) Place to attach muscles • e.g., patella (kneecap)
6) Movement possible through articulation
TYPES OF BONES BONE FORMATION
• Begins as cartilage
1) LONG BONES • Calcifies in utero
• Found in limbs • At birth, fontanels remain
• Made up of a body OSSIFICATION
(diaphysis) & 2 extremities • Bone production process gives bone extreme
(epiphysis) tensile & compressional strength
• Wall consists of dense • Strength
tissue contributor:
• Central/Medullary canal
is filled w/ marrow
Factors contributing BONE GROWTH
2) SHORT BONES 1) Nutrition – calcium consumption; increase
• Found where strength, compactness, & blood calcium triggers release of calcitonin;
limited movement are desired decrease of calcium release Parathyroid
• Includes: Tarsals & Carpals hormone
2) Exposure to Sunlight – UVL on skin cause VitD
production; promotes proper absorption of
calcium
3) Hormonal Secretion – Human growth hormone,
Somatotropin = stimulate activity in epiphyseal
plate
4) Physical Activity – Increase physical exertion =
increase bone density & strength
3) FLAT BONES Bone Maintenance
• Main locations: Skull, scapula & sternum • Osteoblast - Formation of new bone
• Used in spots where protection / muscular • Osteoclast – Destruction / destroy of bone
attachment is desired • Osteocytes – Primary Cell
• Osteogenic – Origin of Cell
Divisions of the Skeletal System
2 main division:
AXIAL SKELETON
APPENDICULAR SKELETON
TRANS BY: IOLA PRINCESS AMADO 1
, SKELETAL SYSTEM
ANATOMY & PHYSIOLOGY
Mr. Eric Mahinay| 1St Semester | BSN – 1B
S.Y. 2023 – 2024
• Inferior conchae – thin curved bones which
project from interior of nasal cavity
AXIAL SKELETON
• Central skeleton that protects & supports vital
organs (brain, heart, lungs)
• Composed of skull & vertebrae
• Mainly flat &
irregular bones
• Support body
along central axis
PARTS OF AXIAL SKELETON
Intervertebral Discs
• Skull – protects brain
• Pads of cartilage between each vertebrae
• Vertebrae – protect spinal cord; keep skeleton
• Cushioning = reduce shock
upright
• High water content
• Ribs – protect lungs & heart; hard surface for
• Aging lowers water
intercostal muscles to move against for
content; drying
breathing
discs
SKULL Division • Herniated (slipped)
• Cranium – 8 bones which hold & protect brain disc – disc
• Facial bones – 14 bones that make up the face; protrudes from
2 are paired spine
Cranium
• Frontal bone – forehead, eyebrows, & superior
section of eye orbital
• Parietal Bone – form most of the superior & Bony Thorax
lateral walls of cranium • Bones connect & protect heart & lungs
• Temporal Bones – inferior to parietal bones • Ribs, Costal Cartilage, & Sternum
• Occipital bone – back & floor of cranium;
foramen magnum (large hole) allows spinal cord RIBS
to meet brain • 12 pairs, each connect to a thoracic
vertebrae
• First 7 pairs = true ribs; attached directly to
sternum
• Last 5 pairs = false ribs; no attachment; last 2
are floating (no sternal attachment)
Facial Bones
• Mandible – lower jawbone
• Maxillary bones (maxillae) fuse to form upper
jaw
• Palatine processes – posterior to maxillae;
forms rear of hard palate
• Zygomatic bones – cheekbones
• Lacrimal bones – inferior of orbital bones;
passageway for tears
• Ethmoid bone – roof of nasal cavity
• Nasal bones – bridge of nose
• Vomer – divides nasal cavity in half
TRANS BY: IOLA PRINCESS AMADO 2
