Presentation on theme: "MUSCULOSKETAL SYSTEM Windsor University School of Medicine"— Presentation transcript:
1 MUSCULOSKETAL SYSTEM Windsor University School of Medicine Premed BiologySeptember 2014
2 Pre Med – Biology Chapter 13 Musculoskeletal System There is more to lectures than the power point slides!Engage your mind
3 SKELETONAnimals have a framework similar to the framework of a home. The framework in animals is called the skeleton. In animals or man, the framework has muscles attached to it instead of walls or roof.“Endoskeleton”Protection, support, and movement of the body
5 Bones serve the following functions: - Protect the vital organs inside the bodyProvide anchor or support to the musclesProduce blood cells
6 The Skeletal System Gives form to the body Protects vital organs Consists of 206 bonesActs as a framework for attachment of musclesDesigned to permit motion of the body
7 Bone cells are living, they can reproduce resulting in the hardening of the bones called “ossification” and bone growthNot only does bone size change, their number also changes. As you grow the number of your bones increases although some bones fuse
9 Skeletal system includes the bones, cartilage, ligaments, and tendons Skeletal system includes the bones, cartilage, ligaments, and tendons. These are tissues that make up the skeleton.A bone is a hard, living tissue and contains blood vessels, nerves and dividing cellsBones are hollow or spongy insideHollow portion of the bone is made of “Marrow”The marrow produces red and white blood cells and stores some of the body’s excess fat
10 Cartilage – Tough, flexible tissue that functions as cusioning Found in lower nose, earlobes, trachea, voiceboxLigaments – Tough, connective tissue that connect one bone to anotherE.g. Hurt when sprain an ankleTendons – Connect a bone to a muscle
11 Skeletal System Bone types Bone structure Bone function Bone growth and metabolism affected by calcium and phosphorous, calcitonin, vitamin D, parathyroid, growth hormone, glucocorticoids, estrogens and androgens, thyroxine, and insulin.
13 There are 3 main parts of the AXIAL skeleton – SkullRib cageBack bone or spinal cordAppendages which includes the hands, arms, shoulders and collar bone and the back appendages composed of the feet, legs, knees and hip bone.
14 VERTEBRAEBACKBONE is made up of thirty-three small bones called vertebraeNeck to tailbone33 bones Total:1. Cervical = 72. Thoracic = 123. Lumbar = 54. Sacral = 55. Coccyx = 4
21 The Spinal ColumnNote that text on graphic may be difficult to read
22 The ThoraxNote that text on graphic may be difficult to read
23 The PelvisNote that text on graphic may be difficult to read
24 The Lower Extremity Hip Thigh Knee Leg Ankle Foot Note that text on graphic may be difficult to read
25 The Upper Extremity Shoulder girdle Arm Elbow Forearm Wrist Hand Note that text on graphic may be difficult to read
26 JointsNote that images are missing. Will any text accompany the images?
27 Types of Muscle (1 of 2) Skeletal (voluntary) muscle Attached to the bones of the bodySmooth (involuntary) muscleCarry out the automatic muscular functions of the body
28 Types of Muscle (2 of 2) Cardiac muscle Involuntary muscle Has own blood supply and electrical systemCan tolerate interruptions of blood supply for only very short periods
29 THE MUSCULOSKELETAL SYSTEM The musculoskeletal system includes all of the bones in a body and the muscles that make them move. It supports the body and protects delicate organs.
30 THE MUSCULOSKELETAL SYSTEM The skeleton consists of bones, ligaments, and cartilage, which are three types of connective tissue.
31 THE MUSCULOSKELETAL SYSTEM The other component of the musculoskeletal system is muscles. Muscle tissue consists of bundles of long cells called muscle fibres, which contain specialized proteins. These proteins cause muscles to contract when signalled by nerve cells.
32 THE MUSCULOSKELETAL SYSTEM Skeletal muscles are attached to the bone by tendons. The other muscle types include smooth muscles (generally located in the intestines) and cardiac muscles in the heart.
33 THE MUSCULOSKELETAL SYSTEM Similar to other organ systems, the musculoskeletal system is susceptible to disease. Osteoporosis is a common disease that involves the loss of bone tissue, which makes bones weak and brittle. It is common among older women. As well, extreme movements can fracture bones and damage muscles, ligaments, and cartilage.Some invertebrates have no rigid frame to give them structure, while others have their skeletal system on the outside (exoskeleton).
34 Structure and function of bone Organization of the skeleton Joints The skeletal systemStructure and function of boneOrganization of the skeletonJointsFunctions of bone (skeleton)Support and protectionBlood cell formationMineral storage (calcium especially)Site for muscle attachment body movement
35 Bones classified by shape: long, short, flat, irregular, roundBone enclosed in periosteum, which is continuouswith tendons and ligamentsblood vessels in periosteumEpiphysis- endsspongy bone contains red marrowcompact bone, articular cartilageDiaphysis- middlecompact bonemedullary cavity- contains yellow marrow (fat)lined with endosteum (squamous epithelium)
37 Compact boneosteocytes within lacunaearranged in concentric circles called lamellaeThis surround a central canal; complex is calledHaversian systemCanaliculi connect osteocytes to central canal andto each other
39 Prenatal developmentskeleton is mostly cartilaginousCartilage cells and then osteoblasts start todeposit mineralsCartilaginous disk (epiphyseal disk) remainsin epiphysisCells eventually stop dividing
41 Adults continually break down and build up bone Osteoclasts remove damaged cells and releasecalcium into bloodOsteoblasts remove calcium from blood and buildnew matrix. They become trappedosteoclasts
42 Types of bone breaksSimple- skin is not piercedCompound- skin is piercedComplete- bone is broken in halfPartial- broken lengthwise but not into twopartsGreenstick- incomplete break on outer arcComminuted- broken into several piecesSpiral- twisted
43 Fracture repairHematoma- blood clot in space between edgesof breakFibrocartilage callus- begins tissue repairBony callus- osteoblasts produce trabeculae(structural support) of spongy bone andreplace fibrocartilageRemodeling- osteoblasts build new compact bone,osteoclasts build new medullary cavity
61 Types of freely movable joints Saddle: carpal and metacarpal bones of thumbBall and socket: shoulder and hip jointsPivot- rotation only: proximal end of radius and ulnaHinge- up and own movement in one plane:knee and elbowGliding- sliding and twisting: wrist and ankleCondyloid- movement in different planes but notrotations: btw metacarpals and phalanges
62 Types of movement and examples (with muscles) flexion- move lower leg toward upperextension- straightening the legabduction- moving leg away from bodyadduction- movong leg toward the bodyrotation- around its axissupination- rotation of arm to palm-up positionpronation- palm downcircumduction- swinging arms in circlesinversion- turning foot so sole is inwardeversion- sole is out
66 Elevation and depression- raising body part up or downAging and bonesboth bone and cartilage tend to deterioratecartilage: chondrocytes die, cartilagebecomes calcifiedosteoporosis; bone is broken down fasterthan it can be builtbones get weak and brittle; tend to fractureeasily
67 Risk factors for osteoporosis Inadequate calciumLittle weight-bearing exerciseDrinking alcohol, smokingBeing female: decreased estrogen secretionafter menopauseSmall frameCaucasian or Asian ethnicity
68 Skeleton and other systems Skin makes vitamin D which enhances calciumabsorptionSkeleton stores calcium for muscle contraction,nervous stimulation, blood clot formationRed marrow- site of blood cell formationCalcium levels regulated byparathyroid hormone and calcitoninkidneys (can help provide vitamin D)digestive system (can release calciuminto blood
70 Growth hormone regulates skeletal growth stimulates cell division in epiphyseal disksin long bonesGrowth stops when epiphyseal disks areconverted to boneWhen excess growth hormone is produced inchildhoodgigantismIn adulthood- acromegaly. Bones can’t growbut soft tissue can
72 When muscle contracts, it shortens and causes movementSkeletal muscles attached to bones by tendonsInsertion- attachment to more movable boneOrigin- less movableFlexors and extensors act on the same jointto produce opposite actions