presentation 15 - musculoskeletal system
DESCRIPTION
TRANSCRIPT
![Page 1: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/1.jpg)
The Musculoskeletal SystemSupport, Protection, Movement and Locomotion
![Page 2: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/2.jpg)
Skeletal Functions
Framework for support Transmits movement Maintains shape Protects internal organs from
mechanical injury Contains and protects the red
bone marrow, one of the hemopoietic (blood-forming) tissues
Mineral reservoir - storage site for excess calcium and phosphorus
Storage of fats – yellow marrow
![Page 3: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/3.jpg)
Cytoskeleton Maintains cell shape
Microfilaments Intermediate filaments Microtubules
Protection Enables motion
Cilia Pseudopodia Flagella
Intracellular transport Cell division
![Page 4: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/4.jpg)
Structural support in plants
Cell walls Collenchyma
and sclerenchyma tissue
Cellulose and lignin
![Page 5: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/5.jpg)
Hydrostatic skeleton
Fluid-filled closed chambers
Internal pressure generated by muscle contraction
e.g. sea anemone and worms
![Page 6: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/6.jpg)
Exoskeleton
Shelled molluscs (CaCO3)
Arthropods (chitin) Hard segments covering
muscles and visceral organs
Muscles are attached to the exoskeleton
Restricts growth and size of insect molting
![Page 7: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/7.jpg)
Endoskeleton
Endoskeleton Internal, often
mineralized, connective tissue
Muscles on the outside Cartilage –
elasmobranchs Other vertebrates –
cartilage replaced by bone as embryo matures and develops
![Page 8: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/8.jpg)
Appendicular and axial skeleton
Axial skeleton (80 bones) axis of the body support and protection of main
organs• Skull • Sternum• Ribs• Vertebral Column + sacrum and
coccyx Appendicular skeleton (126 bones)
anchors appendages to the axial skeleton
• Upper Extremities• Lower Extremities• Pectoral Girdle• Pelvic Girdle
![Page 9: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/9.jpg)
Types of bones
1. Long bones• Long shaft (diaphysis)• Two joint surfaces
(epiphyses)• Mostly compact bone• e.g. femur, tibia, fibula,
radius, ulna 2. Short bones
• Cube-shaped, mostly spongy bone
• e.g. bones of wrist and ankle, patella
3. Flat bones• Thin and curved• e.g. skull and sternum
4. Irregular bones• Irregular and complicated
shapes• e.g. spine and hips
![Page 10: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/10.jpg)
Joints or articulations
Meeting of two bones Types of joints
Immovable Slightly movable Freely movable
![Page 11: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/11.jpg)
Bone Tissue Compact bone
series of Haversian canals concentric layers of bone
cells (osteocytes) new bone formed by
osteocytes Spongy bone
ends of long bones less dense contains red or yellow
marrow Periosteum
outer layer of bone rich in nerve endings, blood,
and lymphatic vessels inner portion forms new
bone or remodels existing bone
![Page 12: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/12.jpg)
Types of bone cells1. Osteoblasts
immature bone cells manufacture hormones
and enzymes that aid in bone mineralization
2. Osteocytes mature osteoblasts in
lacunae (spaces) form bone, maintain
matrix act for calcium
homeostasis3. Osteoclasts
responsible for bone reabsorption and shaping
located on bone surfaces
![Page 13: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/13.jpg)
Bone formation Intramembranous
ossification formation of the flat bones of the skull
Endochondral ossification formation of long bones
![Page 14: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/14.jpg)
Bone remodeling
Resorption of bone (by osteoclasts) followed by replacement of bones (by osteocytes)
Functions to regulate calcium levels, repair damaged bones, and shape and sculpt the skeleton during growth
Rate is regulated by parathyroid hormones (PTH) and Vitamin D
![Page 15: Presentation 15 - Musculoskeletal System](https://reader033.vdocuments.us/reader033/viewer/2022061113/545cbc5caf7959be098b4938/html5/thumbnails/15.jpg)
Disorders of the skeletal system
Osteoporosis Reduced bone density
leading to fractures Rickets and
osteomalacia Softening of bones leading
to deformations and fractures
Arthritis Inflammation of joints
Bone fractures Scoliosis, kyphosis