1. Option B – Muscles Movement and Fitness

2. B1 - Muscles and movement B.1.1 State the roles of bones, ligaments, muscles, tendons and nerves in human movement. Bones provide the structure onto which soft tissue is built, as well as provide a system of levers that allow for movement through muscular contraction. http://jagpower.blogspot.com/2011/10/bones-provide-structure-onto-which-soft.html Ligaments hold bones together http://www.aclsolutions.com/images/Seif_knee%20anatomy02.jpg Muscles do the work….They pull against bones to provide movement. http://www.human-body-facts.com/images/human-body-muscle-diagram.jpg Tendons join muscles to bones. httphttp://www.ehrenchiropractic.com/nervous_sys.jpg://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/8956.jpg Nerves signal muscles to contract.

3. B.1.2 Label a diagram of the human elbow joint, including cartilage, synovial fluid, joint capsule, named bones and antagonistic muscles (biceps and triceps). Outline the functions of the structures in the human elbow joint named. Bending the elbow diagram - put the numbers in the right places! 1. Ulna 2. Radius 3. Contracted biceps brachii muscle 4. Relaxed triceps muscle 5. Humerus 1 2 3 4 5 Straightening the elbow diagram - put the numbers in the right places! 1. Radius 2. Relaxed biceps brachii muscle 3. Humerus 4. Contracted triceps muscle 5. Tendon 6. Ulna http://campaigns2.axappphealthcare.co.uk/medical-encyclopaedia/bending-the-elbow 1 2 3 4 55 5 5 6

4. Match the description on the right with the part on the left : Holds the bones together. Provides a very smooth surface to reduce friction. Acts as a lubricant. Secretes and holds in synovial fluid

5. B.1.4 Compare the movements of the hip joint and the knee joint.

6. Knee: hinge joint - considerable movement in one plane - constrains movement from other two planes flexion (bends) extension (straightens) Hip: ball and socket joint - movement in three planes protraction /retraction: forward and backwards abduction/adduction: sideways in and out rotation: circular movement B.1.4 Compare the movements of the hip joint and the knee joint.

7. B.1.5 Describe the structure of striated muscle fibres, including the myofibrils with light and dark bands, mitochondria, the sarcoplasmic reticulum, nuclei and the sarcolemma.

8. Structure of muscle fibers: Each muscle is made up of bundles of muscle fibres. Each fibre is then made up of even smaller structures, called myofibrils. The myofibrils are sarcomeres attached end to end, which contain light and dark bands, causing the myofibril to appear striped. In between the myofibrils, there are mitochondria to provide the energy for muscle contraction. The sarcoplasmic reticulum surrounds each myofibril B.1.5 Describe the structure of striated muscle fibres, including the myofibrils with light and dark bands, mitochondria, the sarcoplasmic reticulum, nuclei and the sarcolemma.

9. B.1.6 Draw and label a diagram to show the structure of a sarcomere, including Z lines, actin filaments, myosin filaments with heads, and the resultant light and dark bands.

11. B.1.7 Explain how skeletal muscle contracts, including the release of calcium ions from the sarcoplasmic reticulum, the formation of cross-bridges, the sliding of actin and myosin filaments, and the use of ATP to break cross-bridges and re-set myosin heads. A nerve impulse is sent and reaches the neuromuscular junction causing a neurotransmitter to be released into the synapse. This triggers the depolarisation of the sarcolemma, which is the plasma membrane on the muscle fibre. As a result, calcium ions are released from the sarcoplasmic reticulum and this exposes binding sites for myosin to form cross bridges with thin actin filaments. The actin is pulled to the midline. ATP is then hydrolysed at the myosin head, causing it to detach from the actin binding site, then reattach further along the filament. The entire cycle repeats. How a muscle contraction is signalled - Animation - YouTube www.youtube.com/watch?v=CepeYFvqmk4

13. B.1.8 Analyse electron micrographs to find the state of contraction of muscle fibres. If electron micrographs of a relaxed and contracted myofibril are compared it can be seen that: 1. Each sarcomere gets shorter (Z-Z) when the muscle contracts, so the whole muscle gets shorter. 2. But the dark band, which represents the thick filament, does not change in length. This shows that the filaments don’t contract themselves, but instead they slide past each other. http://click4biology.info/c4b/11/hum11.2.htm#8