The Skeletal System

1. The Skeletal System Maribyrnong Secondary College Physical Education

2. - Functions - • Protection of Organs – the brain in the skull, the heart, lungs, liver etc., in the ribcage. • Storage of Mineral Salts – are large percentage of bone is made from Calcium and Phosphorus, which can be both stored and released from bone tissue. • Support gives the body shape and provides structure of muscle to work against. Maribyrnong Secondary College Physical Education

3. - Functions - • Movement – the skeleton provides the structure for muscles to pull against and shorten, creating movement. Maribyrnong Secondary College Physical Education

4. - Functions - • Production of Red Blood Cells – Red Blood Cells are produced in the bone marrow Maribyrnong Secondary College Physical Education

5. - Types of Bone - • Long Bones – have a diaphysis (shaft) and epiphysis (growth plate – the bones of the limbs in particular) • e.g. the bones of the limbs – humerus, radius, ulna, femur, tibia, fibula. • Ribs, Phalanges, Metacarpals and Metatarsals. • The femur is the largest bone in the body. Maribyrnong Secondary College Physical Education

6. - Types of Bone - • Short Bones – bones of the hands and feet, i.e. the carpal (hand) and tarsal (foot) bones. • They have no shaft and are as long as they are wide. Maribyrnong Secondary College Physical Education

7. - Types of Bone - • Flat Bones – the bones of the skull (excluding the mandible), the ilium (pelvis), and scapula. Maribyrnong Secondary College Physical Education

8. - Types of Bone - • Sesamoid Bones – • Bones that are wrapped in tendon or connective tissue • The patella (knee-cap) Maribyrnong Secondary College Physical Education

9. - Types of Bone - • Irregular bones – “one of a kind” bones • The spinal column is comprised of 30 irregular bones – no two are exactly the same shape. • 7 Cervical12 Thoracic5 Lumbar5 Sacral (fused)Coccyx Maribyrnong Secondary College Physical Education

10. Homework • Complete SKELETAL SYSTEM WORKSHEET 1 Maribyrnong Secondary College Physical Education

11. - Vertebral Column - • Each vertebra has a hollow centre through which travels the spinal cord, which control conscious movement of the body. • The vertebra increase in size as they descend from cervical to lumbar region. This helps support the weight of the body. Maribyrnong Secondary College Physical Education

12. - Vertebral Column - • Movement between two vertebrae is very limited, but, • The range of movement of the vertebral column as a whole is great, allowing bending and twisting. • The vertebral column also provides the central structure for the maintenance of good posture. Maribyrnong Secondary College Physical Education

13. - Epiphyseal Plates - • Aka Growth Plates are centres for bone growth. • They are found at the end of the Diaphysis (shaft) of long bones. • These bones are visible under X-ray and may be damaged in injury. Maribyrnong Secondary College Physical Education

14. - Dietary Influence - • Vitamin A – Important for optimal bone development and tooth formation.Sources of vitamin A are liver, kidneys, milk fat, egg yolks and dark green and yellow vegetables. • Vitamin C – Important for collagen production which provides bones with strength and helps to bind calcium and phosphorus to bone to form compact bone.Sources of Vitamin C are citrus fruits and all types of vegetables. Maribyrnong Secondary College Physical Education

15. Homework Maribyrnong Secondary College Physical Education

16. - Dietary Influence - • Vitamin D – Influences the rate of growth in developing bones and promotes calcium absorption from the digestive tract. • Sources of Vitamin D are milk, fish-liver oils and sunlight • Vitamin D deficiency = Rickets Maribyrnong Secondary College Physical Education

17. - Dietary Influence - • Calcium – helps create bone rigidity. • The stores of calcium in bones fluctuate with body’s general demand for this important mineral. • Calcium is required for other bodily functions such as muscular contraction and the operation of the nervous system • Skeletal supplies rise and fall depending on bodily needs and dietary intake. Maribyrnong Secondary College Physical Education

18. - Physical Activity & Skeletal Health - • Positive weight-bearing activities (i.e. running /jumping) have been linked with healthy rates of bone growth in length and width. • This correlation is evident in active versus inactive children. Maribyrnong Secondary College Physical Education

19. - Physical Activity & Skeletal Health - • Lower bone densities become particularly evident in ageing females, for whom osteoporosis is a problem. • Low-level resistance training for women in older age groups has proven to help reduce the chances and severity of osteoporosis. Maribyrnong Secondary College Physical Education

20. - Physical Activity & Skeletal Health - • Overtraining – can result in bone damage e.g. stress fractures in distance runners’ feet, or the limbs of footballers who have excessive training regimes. • Heavy Load, High Intensity, Low Repetition resistance training can damage the epiphyseal plates in growing bones. Maribyrnong Secondary College Physical Education