SKELETAL SYSTEM. Jhia Anjela D. Rivera 1,2 1. Department of Biology, College of Science, Polytechnic University of the Philippines 2

Transcription

1 SKELETAL SYSTEM Jhia Anjela D. Rivera 1,2 1 Department of Biology, College of Science, Polytechnic University of the Philippines 2 Department of Biological Sciences, School of Science and Technology, Centro Escolar University

2 OBJECTIVES To describe the characteristics and functions of bones To classify the bones accordingly To name and be familiarized with the individual bones of the different body regions and their structural markings To correlate the structural features with clinical considerations such as bone response to injury

3 OUTLINE Osteology Classification of Bone according to: Structure Development Shape Location Human skeleton Vertebrae Bones of the Thorax Upper Extremity Lower Extremity Clinical Considerations

4 OSTEOLOGY came from two Greek words oste (bones) + logia (study) Study of bones Bones : organs of the skeletal system Skeletal System: bones and associated cartilages

5 SKELETAL SYSTEM Consists of the specialized supporting connective tissues of the bony skeleton and the associated tissues of joints Includes: Bones of the skeleton Cartilage Ligaments Other connective tissues that stabilize or connect the bones

6 MAJOR FUNCTIONS Support (body weight) Protection (internal organs) Movement (interacts with muscles) Storage (minerals in the blood (Ca and P) Hemopoiesis (Blood Cell Reproduction - red bone marrow)

7 CLASSIFICATION OF BONES Structure Development Shape Location

8 CLASSIFICATION OF BONES Shape Long Short Flat Irregular

9 STRUCTURE Macroscopic Approach: Compact bone Spongy bone Microscopic Approach: Fibrous bone Lamellar bone

10 COMPACT BONE Compact bone denser and has fewer spaces bone substance to bone space ratio is a bigger Usually limited to the cortices of mature bones (cortical bone) Provides strength

11 COMPACT BONE

12 COMPACT BONE Concentric lamellae - circular layers of bone matrix that surround a common center, the central canal Osteon (Haversian System) - consists of a single central canal, its contents, and associated concentric lamellae and osteocytes Circumferential lamellae outer surfaces of compact bones

13 COMPACT BONE Spongy bone Bone substance to bone space ratio is a smaller quantity. This means that there is more empty space and less bone tissue Usually internal, giving additional strength to cortices and supporting the bone marrow

14 SHORT BONE Are about as broad as they are long Nearly cube-shaped or round e.g. wrist (carpals) and ankle (tarsals)

15 FLAT BONES Relatively thin, flattened shape Usually curved e.g. skull bones, ribs, breastbone (sternum), shoulder blades (scapulae)

16 IRREGULAR BONES Bones that do not fit the characteristics of the other three (3) categories e.g. vertebrae and facial bones

17 MICROSCOPIC APPROACH Lamellar bone Fibrous bone

18 LAMELLAR BONE Composed of thin plates (lamellae) of bony tissue Mostly found in mature human body

19 FIBROUS BONE Have more fibers in them Found only in fetus

20 CLASSIFICATION OF BONES Structure Development Shape Location

21 DEVELOPMENT Membranous bones Cartilaginous bones Membrocartilaginous bones

22 MEMBRANOUS BONES also known as dermal bones intra-membranous ossification (ossify from mesenchymal condensations) Examples: bones of the skull and facial bones

23 CARTILAGINOUS BONES intra-cartilaginous ossification (ossify from a cartilage model) Examples: bones of limbs, vertebral column and thoracic cage

24 MEMBROCARTILAGINOUS BONES ossify partly from cartilage and partly from mesenchymal condensations Examples: clavicle, mandible, occipital, temporal and sphenoid

25 MEMBROCARTILAGINOUS BONES ossify partly from cartilage and partly from mesenchymal condensations Examples: clavicle, mandible, occipital, temporal and sphenoid

26 DIVISIONS OF SKELETAL SYSTEM SKELETAL SYSTEM AXIAL SKELETON Composed of the bone along the central axis of the body APPENDICULAR SKELETON Consists of the bones of the appendages

27 AXIAL SKELETON Divided into the skull, auditory ossicles, hyoid bone, vertebral column and thoracic cage or rib cage Forms the upright axis of the body Protects the brain, spinal cord and the vital organs housed within the thorax

28 APPENDICULAR SKELETON Consists of the bones of the upper and lower limbs and the girdles by which they are attached to the body