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]
Presentation and notes
The presentation is designed to help your understanding.
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.
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
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)