11.2 Study Guide for Muscles & Movement
TOPIC AHL 11.2 (pages 291 to 299)
Define the following Vocabulary Words:
locomotion
Tendons
Nerves
Muscles
Ligaments
bones
Elbow joint
Cartilage
Synovial joints
Synovial membrane
Humerus bone
Radius bone
ulna
Synovial fluid
Joint capsule
Antagonistic muscles
Biceps Muscle
Triceps Muscle
Ball & Socket Joint
Hinge Joint
Skeletal muscle
Action potential
Myofibrils
Sarcoplasmic reticulum
Sarcolemma
Z-ines
Actin filaments
Myosin heads
cross-bridges
muscle fibres.
ATP
Address the Learning Objectives Below:
11.2.1 State the roles of bones, ligaments, muscles, tendons and nerves in human movement.
11.2.2 Label a diagram of the human elbow joint, including cartilage, synovial fluid, joint capsule,
named bones and antagonistic muscles (biceps and triceps).
11.2.3 Outline the functions of the structures in the human elbow joint named in
11.2.4 Compare the movements of the hip joint and the knee joint.
o Video analysis of motion is possible here.
11.2.5 Describe the structure of striated muscle fibres, including
 the myofibrils with light and dark bands,
 mitochondria,
 the sarcoplasmic reticulum,
 nuclei and the sarcolemma.
11.2.6 Draw and label a diagram to show the structure of a sarcomere, including
o Z lines,
o actin filaments,
o myosin filaments with heads,
o and the resultant light and dark bands.
11.2.7 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.
11.2.8 Analyse electron micrographs to find the state of contraction of muscle fibres.
o Muscle fibres can be fully relaxed, slightly contracted, moderately contracted and fully
contracted.
Practice Questions (optional)
1.
Label the following features and state their function in movement.
Joints
a.
‘moment’ or pivot for movement (1)
b.
c.
d.
e.
f.
2. The elbow.
3. Outline the antagonistic nature of the action of muscles in the human body, using the elbow as an example.
Flexing (bending)
Extending
Biceps
Triceps
4. Compare the action of the hip and knee joints.
Hip (similar to shoulder)
Knee
Type of joint
Ball and socket
Range of movement
Bones
Lever
Femur
Flex/ effort
Extend/ effort
Image
5. Label these structures of a muscle cell.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
6. Outline the need for large numbers of mitochondria in muscle cells.

7. Muscle cells contract as a result of nerve impulses.
a. State the part of the motor neuron which connects to the muscle cells

b. Identify the neurotransmitter used at the neuromuscular junction.

8. Label the structures of the sarcomere:
a.
b.
c.
d.
e.
9. Identify the number of complete number of sarcomeres in this EM image:

Sarcomeres =
10. Explain the contraction of skeletal muscle.
Include: sarcolemma, sarcoplasmic reticulum, Ca2+, actin binding sites, cross bridges, myosin heads, ATP.
Action potential (AP) reaches terminal end of motor
neuron. ACh is released into synapse. Action potential
is initiated in the muscle cell membrane.
Sarcoplasmic reticulum…
11. Compare these two electron micrographs of a skeletal muscle sarcomere.
Contracted or
relaxed?
Sarcomere length
Shorter
Z-bands
Closer
H-bands
No change
Light bands
Dark bands
No change
12. Deduce the relative roles of actin and myosin fibres from this image:
a. Myosin fibres move, actin fibres remain in position.
b. Actin fibres move, myosin fibres remain in position.
c. Both actin and myosin fibres move.
d. Neither actin nor myosin fibres move.
Works Cited
1. Allott, Andrew. IB Study Guide: Biology for the IB Diploma. s.l. : Oxford University Press, 2007. 978-0-19-915143-1.
2. Mindorff, D and Allott, A. Biology Course Companion. Oxford : Oxford University Press, 2007. 978-099151240.
3. Clegg, CJ. Biology for the IB Diploma. London : Hodder Murray, 2007. 978-0340926529.
4. Campbell N., Reece J., Taylor M., Simon. E. Biology Concepts and Connections. San Fransisco : Pearson Benjamin
Cummings, 2006. 0-8053-7160-5.
5. Taylor, Stephen. Science Video Resources. [Online] Wordpress, 2010. http://sciencevideos.wordpress.com.
6. Burrell, John. Click4Biology. [Online] 2010. http://click4biology.info/.
7. IBO. Biology Subject Guide. [Online] 2007. http://xmltwo.ibo.org/publications/migrated/productionapp2.ibo.org/publication/7/part/2/chapter/1.html.