Essential idea: The roles of the musculoskeletal system are movement, support and protection.
The rigid nature of bone both supports and protects organs within the body. It also gives a structure for muscles to pull, by their contraction, to create movement.
Understandings, applications and skills
11.2.U1 | Bones and exoskeletons provide anchorage for muscles and act as levers. |
11.2.U2 | Synovial joints allow certain movements but not others. |
11.2.U3 | Movement of the body requires muscles to work in antagonistic pairs. |
11.2.U4 | Skeletal muscle fibres are multinucleate and contain specialized endoplasmic reticulum. |
11.2.U5 | Muscle fibres contain many myofibrils. |
11.2.U6 | Each myofibril is made up of contractile sarcomeres. |
11.2.U7 | The contraction of the skeletal muscle is achieved by the sliding of actin and myosin filaments. |
11.2.U8 | ATP hydrolysis and cross bridge formation are necessary for the filaments to slide. |
11.2.U9 | Calcium ions and the proteins tropomyosin and troponin control muscle contractions. |
11.2.A1 | Antagonistic pairs of muscles in an insect leg. |
11.2.S1 | Annotation of a diagram of the human elbow. [Elbow diagram should include cartilage, synovial fluid, joint capsule, named bones and named antagonistic muscles. ] |
11.2.S2 | Drawing labelled diagrams of the structure of a sarcomere. [Drawing labelled diagrams of the structure of a sarcomere should include Z lines, actin filaments, myosin filaments with heads, and the resultant light and dark bands. ] |
11.2.S3 | Analysis of electron micrographs to find the state of contraction of muscle fibres. [Measurement of the length of sarcomeres will require calibration of the eyepiece scale of the microscope. ] |
[Text in square brackets indicates guidance notes]
Starters
Dr Alice Roberts looks at antagonistic muscles by body painting
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Hank from Crash Course with a high speed introduction to the Muscular system
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Presentation and notes
The presentation is designed to help your understanding.
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The 11.2 Movement notes - the bottom line template can be used as a note construction template in itself or as a checklist if you are using your own or another template such as the Cornell style template.
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Weblinks
An animated guide to the human body : The muscle edition by Eleanor Lutz
Antagonistic muscle pair by Freezeray Hipjoint by Freezeray Muscle contraction by Cengage learning |
Animation of how the protein fibres cause changes in band size by the University of Western Australia
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Nature of science
Developments in scientific research follow improvements in apparatus - fluorescent calcium ions have been used to study the cyclic interactions in muscle contraction. (1.8)