ANATOMYSTRUCTURE – the bones of the skeleton provide protection

ANATOMYSTRUCTURE OF THE SKELETAL SYSTEMThe bones in the skeletal system are divided into two parts, the axial skeleton and appendicular skeleton.Axial Skeleton – The axial skeleton is the core area of the body and consists of the bones that provide support for the body.  It contains 80 bones out of the 206 and consists of the skull, the facial bones and the bones in the torso. Appendicular Skeleton – The appendicular skeleton consists of the bones of the limbs and the girdles that join them to the torso (the axial skeleton.)https://www.buzzle.com/articles/skeletal-system-facts.html FUNCTION OF THE SKELETAL SYSTEMSupport – the skeleton provides a rigid framework that supports the body and gives it its shape. The skeletal system changes with growth to allow essential bodily functions to take place, for example, the rib cage increase in size to enable the lungs to fully inflate to breathe efficiently. The skeletal system provides support for the body by keeping the internal organs in their correct place. The strong bones in the spine and those in the legs allow humans to stand upright by supporting the entire body and its weight.Protection – the bones of the skeleton provide protection for the internal organs by surrounding them. For example,the cranium protecting the brain or the ribs protecting the heart and the lungs. Bones are hard living tissues that are flexible to resist breaking. The flexibility is due to collagen in the bones and they get their strength from their minerals (calcium and phosphorus.) The combination of the two gives the bones the ability to absorb impact and protect the internal organs behind them.Movement – the bones of the skeleton provide a large surface area for the attachment of muscles by ligaments and tendons. The long bones in particular provide a system of levers against which the muscles can pull. The skeletal system and the muscular system work together as one to enable movement and stability of the body. When a muscle contracts, the bone is pulled to produce a movement. The bones shape and how they fit together with other bones at joints (e.g. hinge joints) allow for different types of movementBlood production – within the larger bones, there is a spongy tissue called bone marrow. There are two types of bone marrow, red and yellow. Yellow marrow produces the bodies red blood cells and is generally found at the ends of long bones such as the humerus and the femur. It can also be found in some flat bones such as the pelvis and sternum. However, red marrow is responsible for producing the white blood cells for the body and is usually produced in the shafts of long bones. Mineral Storage – the bones of the skeletal system have storage capabilities for vital minerals such as calcium and phosphorus, which can be used to help carry out important bodily functions. They are released from the bones into the bloodstream to maintain levels needed for the bodies functions and processes. For example, calcium ions help with muscle contractions and help to control the flow of other ions, especially those involved with the transmission of nerve impulses. https://www.livestrong.com/article/115165-functions-skeleton/ LOCATION OF THE MAJOR BONEShttp://www.biologydiscussion.com/human-beings/skeletal-system/skeletal-system-of-human-beings-with-diagram/52551 http://www.tpub.com/corpsman/9.htm TYPES OF BONELong boneSome examples of long bones in the body include the femur, humerus and the tibia, which are some of the longest bones in the body. However, other examples of long bones are the metacarpals, metatarsals and the phalanges which are some of the smallest bones in the body. When classifying a long bone you look at the length of the bone compared to its width. If the bone is a lot longer than it is wide, it is classed as a long bone. The classification also includes the bone having growth plates (epiphysis) at either end of it, it should have a hard outer surface of a more compact bone and the inside of it should include cancellous bone (spongy) that contains bone marrow. Each end of the bone is covered in a protective cartilage called hyaline cartilage that is shock absorbent which protects the bone from damage. Short boneShort bones are classified by looking at the length and width, just like long bones. However, a short bones length and width are approximately the same, making them as long as they are wide. Short bones provide great support and stability but they have limited movability, therefore support is their main function. Some examples of short bones are the bones in the wrist and the foot – the carpals and the tarsals. Short bones only have a thin layer of hard, compact bone on the surface unlike the long bones but they cancellous bone inside it that contains large amounts of bone marrow in it like long bones.http://reidhosp.adam.com/content.aspx?productId=39&pid=1&gid=002298&print=1 Flat boneFlat bones are strong, flat bones that provide protection to the vital internal organs of the body such as the heart and the lungs and act as a base for muscular attachment (creating the musculoskeletal system.) An example of a flat bone is the cranium. The cranium protects the brain which is a vital organ in the body. Other example include the sternum, the scapula and the ribs. Anterior surfaces are formed of compact bone along with posterior surfaces to provide strength to the provides for protection. The centre of the bone includes cancellous bone just like long and short bones but the amount of bone marrow in flat bones vary in each one. The highest amount of red blood cells are formed in flat bones.https://www.tes.com/lessons/AYnSgqtaXkPKFA/copy-of-bone-anatomy Irregular boneIrregular bones are the bones in the body that don’t really fall into any of the bone categories. They are unclassified due to their non-uniform shape. Some examples of irregular bones are the mandible, the vertebrae and the sacrum. The consist of mainly cancellous bone and have a thin layer of compact bone on their outer surface. https://commons.wikimedia.org/wiki/File:Irregular_bones_-_anterior_view_-_with_legend.png Sesamoid boneSesamoid bones are the final type of bone in the skeletal system. They are usually either short bones or irregular bones that are embedded inside a tendon. The patella (the kneecap) is the main example of a sesamoid bone as that bone sits within the tendon of the patella or the quadriceps. Other examples are the pisiform that are that smallest bones of the carpals and two small bones that are found at the base of the first metatarsal. Sesamoid bones are usually present in the tendons that pass over joints where it serves to protect the tendon.   http://mediphotos.blogspot.co.uk/2012/03/sesamoid-bones-functions-and-mechanism.html CROSS SECTIONS JOINTS IN THE BODY   Bones support the body and protect its vital organs but for movement to occur, the bones in the body must be linked. This is where joints are introduced. Joints form where two or more bones meet each other, known as an articulation. The three types of joints are synovial, fixed and semi-movable. SYNOVIAL JOINTSSynovial joints are also known as freely movable due to the high level of mobility they have. They usually consists of two or more bones and their ends are covered in a articular cartilage which allows bones to move over one another without creating much friction. They are the most common joints in the skeletal system. Synovial joints are surrounded by a fibrous capsule that is lined with synovial membrane. The synovial membranes function is to secrete synovial fluid into the joint cavity, lubricating it to nourish the joint. The joint capsule is kept together by strong bands of connective tissue called ligaments. Ligaments provide strength which helps to prevent dislocation whilst also being flexible to allow movement. All of these joints have an outer sleeve or a joint capsule to hold the bones in their place and protect the joint.TYPE OF SYNOVIAL JOINTDESCRIPTIONBall and socket jointBall and socket joints can be found in the shoulder bone and the hip bone. One end of a bone has a ball like structure and the end of the opposite bone is shaped like a cup. The two bones are then able to fit into each other and allow movement in all directions.  Hinge jointHinge joints can be found at the elbow and the knee and only allow movement in one direction. They only allow extension or flexion at the joint.Saddle jointSaddle joints can be found in the thumb. Their surfaces are concave and convex and they allow forwards and backwards movement along with side to side movement. Gliding joint Gliding joints are located in the ankles and the wrists. They do allow a range of movement however, it is limited due to ligaments or a bony prominence (e.g. the carpals and tarsals of the wrist and ankle.) They are commonly found between flat bones, hence the name gliding as they glide past each other which allows the movement.Pivot jointPivot joints can be found in the neck as they connect the head to the body. A ring of a bone fits over the peg of another bone, allowing rotational movement. Condyloid jointCondyloid joints, also named ellipsoid joints are modified version of a ball and socket joint. They can be found in the wrist and they allow forwards and backwards movement as well as side to side movement. Ligaments once again prevent rotation just like in the gliding joints. A bump on one bone sits in the hollow of another bone, this is known as a biaxial and this allows the bending and straightening of the joint. Diagrams of the synovial jointshttps://www.pearsonschoolsandfecolleges.co.uk/FEAndVocational/SportsStudies/BTEC/Level3BTECNationalSport/Samples/Takeapeek/9781846906510_takeapeek.pdf Fixed jointsFixed joints, also known as fibrous or immovable joints, do not move. They interlock and overlap and are held together by bands of tough, fibrous tissue. An example is between the plates in your cranium. Semi-movable jointsSemi movable joints can partly move in a small range of direction but are held in place withligaments and cushioned cartilage that is in place to stop it wearing away. An example of a semi movable joint is the vertebral column. This is located in the spine and allows a small rotational movement.Types of movement. Flexion is when you bend the limb and reduce the angle at the joint. An example of this movement could be when you bend your leg in preparation for kicking a football as you need to bend your leg to give it power for when you eventually kick the ball.Extension is the opposite to flexion and is when you straighten your limb to increase the angle at the joint. An example could be when you a netball takes their shot as they have to straighten their arms to push the ball upwards and into the net. Abduction is when a limb is moving away from your body. An example of this could be when a gymnast does a side step as their leg is moving away from the midline of the body Adduction is the movement of a limb towards the body, it is the opposite to abduction. An example of this movement could be when a swimmer is performing breaststroke. Rotation is the circular movement of a limb. An example of rotation could be when a server throws the ball at the wickets in a cricket match. The rotation of the limb gives the arm more power to throw the ball fastest, making it harder for the batter to hit. Pronation is the inward rotation of the forearm where the palm of the hand is facing down and backwards. An example of this occurring is during a ping pong game when the player does a forehand topspin shot.Supination is the outward rotation of the person’s forearm where the palm of the hand is face up and forwards. An example of this movement is a backhand topspin shot in a ping pong match. Plantar flexion is when a person’s toes point downwards when the ankle straightens. An example of this could be when a netball player tries to block a shot by jumping high in front of their opponent. The movement gives the player more power to push off the ground harder to get as high as possible for them to block the shot. Dorsiflexion is the opposite of plantar flexion and is the upward movement of the foot which pulls the toes towards the knee. A simple example of this is walking. P3/P4 MUSCULAR SYSTEMMUSCLEFUNCTIONINSERTION(the bone that muscle puts in action)ORIGIN(the nearest flat bone)Biceps brachiiFlexes lower armRadius ScapulaTricepsExtends lower arm Olecranon ProcessHumerus ScapulaPectoralis majorFlexes upper arm and adducts upper armHumerus Sternum ClavicleRib cartilageLatissimus dorsiExtends upper arm Adducts upper armHumerusVertebraeIliac crestDeltoidAbducts, flexes and extends the upper armHumerusClavicleScapula acromionIliopsoasFlexes trunk and thighIlium VertebraeFemurIliumVertebraeFemur Gluteus mediusGluteus minimusAbducts thighFemur Ilium Gluteus maximusExtends thighFemur IliumSacrumCoccyx Hamstring groupBiceps femorisSemimembranosus Semitendinosus Flexes lower leg Extends thighTibiaFibulaIschium Femur Quadricep groupRectus femorisVastus medialisVastus intermediusExtends lower legFlexes thighTibia (via patella tendon)Ilium Femur Sartorius Flexes hip and kneeAnterior superiorIliac spineTibia Adductors LongusMagnusbrevisAdducts thigh Femur (linea aspera)Pubic boneGastrocnemiusPlantar flexionFlexes kneeCalcaneusFemur SoleusPlantar flexionCalcaneusFibulaTibiaTYPES OF MUSCLESThe three main types of muscles in the body are:The Skeletal muscle is a long, thin muscle that is attached to the bone by a tendon. They are voluntary muscles meaning they are under conscious control. https://commons.wikimedia.org/wiki/File:Illu_muscle_structure.jpg The Smooth muscle is involuntary muscle that is moved without a conscious thought and functions under the control of the nervous system. They can be found in the digestive system and the blood vessels where they help to regulate digestion and blood pressure.       http://tenderness.co/smooth-muscle-diagram/ The Cardiac muscle is only found in the wall of the heart and is a continuously working muscle. It is also involuntary meaning it works without being under conscious control, just like the smooth muscle. It is made striated tissue that has its own blood supply. The cardiac muscle contractions help to force blood through the blood vessels and around the body.http://accessmedicine.mhmedical.com/content.aspx?bookid=574=42524596 FUNCTION OF THE MUSCLES IN THE BODYThe only function that the muscles in the body have is movement. To move, the muscles contract. This pulls the bone towards the muscle which brings them together around the joint. Bones are like levers and joints are like the fulcrum. Muscles must cross a joint, otherwise, there would be no movement. Muscles are in a constant state of contraction, it isn’t a full contraction, it’s only partial. This is so the body can react quickly and also to give the body structure to prevent it from collapsing. MOVEMENT OF THE MUSCLES Antagonistic pairsMuscles don’t work individually, they work in pairs or groups that work together to create movement. Muscles only act by contracting and pulling, not pushing. When muscles contract, one end will remain stationary (origin) whilst the other end moves (insertion). Many of the muscles work together in antagonistic pairs. This is where one muscle contracts whilst the other relaxes. An example, of this is when an individual bends their elbow (flexion). The bicep contracts (the agonist) to create this movement and the tricep relaxes (the antagonist). Agonist/Prime moverThis is the contracting muscle that is responsible for the movement. It is the muscle that becomes shorter in order to move the bone.   AntagonistThis is the opposite muscle to the agonist. It is the muscle that relaxes when the agonist contracts. If the antagonist didn’t relax, then the movement wouldn’t occur. http://encyclopedia.lubopitko-bg.com/Skeletal_Muscles_of_the_Body.html SynergistThe synergists are responsible for the stabilising of a joint where a movement is occuring. Synergists work together to allow the agonists to operate in a more efficient way. They work with agonists to direct and control a movement by changing the direction of the pull on the agonists to it’s best position. FixatorFixators are responsible for stopping unwanted movement that may occur throughout the body by fixing/stabilising joints that become unstable. The fixator muscles stabilise the origin to allow the agonist to achieve maximum contraction. When riding a bike, the quadriceps and the muscles in the calf are the agonists whilst the hamstrings and shin muscles are the antagonists. The other muscles in the leg act as the synergists whilst the back muscles and the abdomen are the fixators and stop an individual from falling off their bike. MUSCLE CONTRACTIONS IsometricIsometric contraction are where the length of a muscles doesn’t change and the angle of the joint doesn’t alter. The muscle holds a static position. An example of this could be when an individual stops halfway through a squat and holds that position. This type of muscle contraction is easy to do, however, it quickly leads to fatigue in the muscle that is contracting. ConcentricConcentric contraction is where the muscle shortens against a resistance. An example of this could be the bicep curl. The bicep shortens which brings the forearm towards the upper arm. This muscle contraction is also known as the positive phase of a muscle contraction. EccentricEccentric contraction is where the muscle that has contracted returns to normal length after it has shortened against a resistance. They are the negative phase of contraction. For example, when lowering the arm to starting position in a bicep curl, the muscles are working against gravity and are basically acting as a brake. Eccentric contractions occur activities no matter what the intensity is, and are a significant factor in the stimulus that promotes gains in the muscles.IsokineticWhen isokinetic contractions occur, the muscle is contracting and shortening at a constant rate of speed. It isn’t a common contraction, meaning special equipment is required to measure them, called a isokinetic dynamometer. This type of training is very efficient in increasing muscular strength and endurance. TYPES OF MUSCLE FIBRES Skeletal muscles contain a mixture of fibre types. The mix of fibres varies from individual to individual, and within the individual from muscle group to muscle group. To a large extent this fibre mix is inherited. However, training can influence the efficiency of these different fibre types. Two main types of striated skeletal muscle can be distinguished on the basis of their speed of contraction: Type 1 (slow twitch) and Type 2 (fast twitch). Type 1 – Slow twitchThe first type of muscle fibre is slow twitch. They are called slow twitch fibres as they contract slowly and without a lot of force. These fibres can contract many times before they become fatigued meaning these muscle fibres are more common in long distance runners and other aerobic/muscular endurance sports. Their blood supply is rich and contains a lot of mitochondria meaning more aerobic metabolism will occur, this being beneficial for long distance runners like Mo Farah. This is also why they are called red fibres as they have a lot of blood rich myoglobin, creating the darker red look. Slow twitch fibres have a high capacity to make aerobic respiration more efficient. They also have a lot of capillaries meaning more oxygen will be able to reach the muscles. Slow twitch muscle fibres have high levels of myoglobin and mitochondria. These carry oxygen around the body, again being beneficial to endurance sportsmen.Type 2 – Fast twitchFast twitch muscle fibre contractions are very quick and they provide speed and strength to an athlete, however, they do fatigue a lot faster compared to slow twitch fibres meaning they are more common in sprinters like Usain Bolt and other sports that require quick actions. Usain Bolt’s muscles need to have short, intense bursts of energy to enable him to be as quick as he can, therefore, fast twitch fibres will be more efficient than slow twitch fibres in his sport. These muscle fibres don’t have many mitochondria or myoglobin, therefore, not much oxygen or energy reaching the muscles. However, they aren’t really needed anyway as sprinters don’t needed a lot of oxygen/energy to go to their muscles as their sport only last for around 10 seconds, compared to long distances runners that could go on for hours meaning a lot of oxygen would be needed. The way sprinters get their energy for when they run is ATP and glycogen, they are their main energy stores. However, ATP sources can rapidly deplete, lactic acid is a byproduct of the breaking down of glycogen, therefore, fast-twitch fibres can only be active for a short space of time. The problem with fast twitch muscle fibres is that they become fatigued very easily, however, this isn’t much of a disadvantage as sprinters aren’t running for long so they don’t feel it. Finally, fast twitch fibres have a low amount of capillaries, this would be a disadvantage for marathon runners but not for sprinters. That is why these muscle fibres are more suited to fast paced sports.Fast twitch fibres are subdivided into two types:Type 2aType 2a fibres are fast-contracting and able to produce a great force, but are also resistant to fatigue. These fibres have many myoglobin, a lot of mitochondria and a high density of capillaries. Type 2a fibres are red, they are able to generate a lot of ATP by processes called oxidative metabolic processes. ATP can be split at a high rate, they have very fast contractions and are resistant to becoming fatigued. These fibres are suited to middle-distance events. Type 2b Type 2b fibres contract rapidly and have the capacity to produce large amounts of force, but they fatigue faster, making them better suited to anaerobic activities. These fibres don’t have a lot of myoglobin, mitochondria or capillaries compared to type 2b. Type 2b fibres are white, they aren’t able to continuously supply skeletal muscle fibres with the needed amounts of ATP, they fatigue easily, split ATP at a rapid rate and have fast contractions. They depend on anaerobic metabolism and are recruited for short, intense sports. CHARACTERISTICS OF THE MUSCLE FIBRESCharacteristic of muscle fibersType 1Type 2aType 2bColourRedRedWhiteContraction speedSlowFasterFasterAerobic or anaerobicAerobic AerobicAnaerobicType of activity Endurance basedMiddle-distanceSpeed and strength basedEnduranceCan contract repeatedly Fairly resistant to fatigueEasily exhaustedForceExert minimal forceExert medium forceExert great forceType of sport associated with each fibreEndurance sports such as running, cycling, swimmingMiddle-distance running such as 800m and 1500mExplosive sports such as sprinting, jumping, throwing, weightlifting https://www.pearsonschoolsandfecolleges.co.uk/FEAndVocational/SportsStudies/BTEC/Level3BTECNationalSport/Samples/Takeapeek/9781846906510_takeapeek.pdf

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