Bones & Muscles: Functions & Structures

1. Skeletal, Muscular, & Nervous System Chapter 15

2. Functions of the skeletal system • Provides a living structure for your body • Supports your upper body and head • Plays a crucial role in movement • Protects internal tissues and organs from trauma • Store minerals

3. Structure of the skeleton • You have 206 bones in your body • Axial Skeleton – the 80 bones of the skull, spine, ribs, vertebrae, and sternum or breastbone • Appendicular skeleton – the remaining 126 bones of the upper and lower limbs, shoulders, and hips

4. Types of bones • Long Bones – your arms and legs • Humerus is the bone in your upper arm • Diaphysis main column of a long bone • Epiphysis is the end of a long bone

5. Types of bones • Short Bones – are almost equal in length and width • Small bones in the wrist & ankles

6. Types of bones • Flat Bones – somewhat thinner and much flatter than other bones • The skull, scapula, or shoulder blade are all examples

7. Types of bones • Irregular Bones – are irregularly shaped • Some facial bones & vertebrae are examples

8. Cartilage • Cartilage – a strong, flexible connective tissue • Found at the ends of long bones • End of the nose • Within the outer ear • In some joints like the knee & acts like a cushion

9. Cartilage • Ossification – is the process by which bone is formed, renewed, & repaired • This happens early in the embryonic developmental stage

10. Joints • Joints are points at which bones meet

11. Types of Joints • Ball-&-socket joint – formed when the rounded head of one bone fits into the rounded cavity of an adjoining bone • Hinge joint – found at the elbow, knee, ankle & fingers • Pivot joints – allow limited rotation or turning of the head

12. Types of Joints • Ellipsoidal joints – such as the ones in your wrist, have an oval-shaped part that fits into a curved space • Ligament – a band of fibrous, slightly elastic connective tissue that attaches bone to bone • Tendon – a fibrous cord that attaches muscle to the bone

13. Care & Problems of the Skeletal System Lesson 2

14. Problems of the skeletal system • Fractures – any type of break in a bone • They can be either compound or simple • Compound – one in which the broken bones protrudes through the skin • Simple – one in which the broken bone does not protrude

15. Types of Fractures • Hairline fracture –the fracture is incomplete & the two parts of the bones do not separate • Transverse fracture – the fracture is completely across the bone • Comminuted fracture – the bone shatters into more than 2 pieces

16. Osteoporosis • You can only develop bone now while you are growing. Your habits now will affect you later in life • Osteoporosis – a condition in which progressive loss of bone tissue occurs • Usually affects millions of older Americans & has no warning signs

17. Scoliosis • Scoliosis – is a lateral, or side-to-side, curvature of the spine • This may exist at the time of birth, or it can develop during childhood • Treatments include wearing braces to help straighten the spine and possibly even surgery in severe cases

18. Injuries to Joints • Dislocation – results when the ligaments that attach the bone at the joint are torn as the bone slips out of place • Torn cartilage – can result from a sharp blow or the twisting of a joint • Bursitis – results from the inflammation of a fluid-filled sac called the bursa

19. Injuries to Joints • Bunion – is a painful swelling of the bursa in the first joint of the big toe • Arthritis – is the inflammation of a joint • Repetitive motion injury – is damage to tissue caused by prolonged, repeated movements such as in computer work, sewing or assembly line work

20. The Muscular System Lesson 3

21. Functions of the muscular system • Help you to breathe, make your heart beat, and move food through your digestive system • Voluntary muscles – muscles you knowingly move • Involuntary muscles – muscles that move without your conscious control

22. Structure of the Muscular System • Muscles are made up of hundreds of long cells called fibers • Muscles work by means of two complementary or opposing actions • Contraction – shortening of the muscles • Extension – lengthening of the muscles

23. Types of Muscles • Smooth muscles – act on the lining of passageways and internal organs (they are involuntary) • Skeletal Muscles – are attached to bone and cause body movements (they are voluntary) • Flexor – the muscle that close a joint • Extensor – the muscle that opens a joint

24. Types of Muscles • Cardiac muscles – a type of striated muscle that forms the wall of the heart (it is an involuntary muscle)

25. Care of the Muscular System • Muscle tone – the natural tension in the fibers of a muscle • Regular physical activity can help to keep your muscles toned

26. Problems of the Muscular System • Bruise – is an area of discolored skin that appears after an injury causes the blood vessels beneath the skin to rupture and leak • Muscle sprain or strain – a strained muscles results when a muscle is stretched or partially torn as a result of overexertion

27. Problems of the Muscular System • Muscles strains are treated using the • Rest • Ice • Compression • Elevation • Or RICE method

28. Problems of the Muscular System • Tendonitis – or the inflammation of a tendon • Caused by injury, overuse, or natural aging • Hernia – when an organ or tissue protrudes through an area of weak muscle

29. Problems of the Muscular System • Muscular Dystrophy – is an inherited disorder in which skeletal muscle fibers are progressively destroyed

30. The Nervous System Lesson 4

31. Functions of the nervous system • It coordinates all of the activities in your body including • Breathing • Or digesting food to sensing pain or feeling fear

32. Functions of the nervous system • The brain, spinal cord, and nerves all work together • The nervous system has 2 main divisions • Central Nervous System • Peripheral Nervous System

33. Functions of the nervous system • Central Nervous System – consists of the brain and spinal cord • Peripheral Nervous System – gathers information from inside and outside your body

34. Neurons • Neurons – are nerve cells

35. Neurons • Cell body – the cell body of a neuron contains the nucleus, the control center of the cell • Neuron cells have limited ability to repair damage or replace destroyed cells

36. Neurons • Dendrites – are branched structures that extend from the cell body in most neurons • They receive information from other neurons or sensory receptors and transmit impulses toward the cell body

37. Neurons • Axons – transmit impulses away from the cell body and toward another neuron, muscle cell, or gland • Axons that are covered by a myelin sheath can transmit impulses faster than those without a cover

38. Central Nervous System • Parts of the central nervous system include the spinal cord & the brain • Brain – the main job of the brain is to integrate & control the activities of the nervous system

39. Parts of the brain • Cerebrum – the largest and most complex part of the brain, its job is to focus on thought, learning and memory • Frontal lobe – controls voluntary movements & has a role in the use of language • Parietal lobe – is involved with sensory information such as heat, cold, pain, touch a, & body position

40. Parts of the brain • Occipital lobe – controls the sense of vision • Temporal lobe – controls the senses of hearing & smell; it is also involved with memory, thought, and judgment

41. Parts of the brain • Cerebellum – the second largest part of the brain, its job is to coordinate the movement of skeletal muscles

42. Parts of the brain • Brain stem – is a 3” stalk of nerve cells & fibers that connects the spinal cord to the rest of the brain • Medulla oblongata – is the lowest part of the brain stem, helps to regulate heartbeat & respiratory rate as well as reflexes such as sneezing, coughing, & vomiting

43. Medulla oblongata • Has 3 parts to it • Pons – located just above the medulla. This is the pathway connecting nerve impulses to other areas of the brain. Helps regulate breathing • Midbrain – the highest portion of the brain stem. Controls eyeball movement

44. Medulla oblongata • Thalamus – an important relay center for incoming sensory impulses. Receives information through the eyes and the ears • Hypothalamus – controls balance and various body processes to regulate body temperature, appetite awareness, and regulates sleep • Pituitary gland – controls metabolism, sexual development & emotional responses

45. The Peripheral Nervous System • Includes all the nerves that are not part of the Central Nervous System (CNS) • The Peripheral Nervous System can be divided into 2 parts • Autonomic Nervous System • Somatic Nervous System

46. Autonomic Nervous System • Controls involuntary actions such as digestion & heart rate • The Autonomic nervous system is broken down into 2 parts • Sympathetic nervous system • Parasympathetic nervous system

47. Sympathetic nervous system • Cause your heart rate to increase and blood vessels leading to your muscles to dilate • Reflex – s spontaneous response of the body to a stimulus

48. Parasympathetic nervous system • During rest it opposes the actions of the sympathetic system by slowing body functions • Slows down heartbeats, opens blood vessels, and lowers blood pressure

49. Somatic Nervous System • Consists of sensory neurons that relay messages from receptors in the eyes, ear, nose, tongue, & skin to the CNS & motor neurons that carry impulses from the CNS to the skeletal muscles

50. Care & Problems of the Nervous System Lesson 5