2. The Musculoskeletal System And Exercise Flashcards
What is the outer membrane of a muscle called?
Epimysium.
What is the term given to a bundle of muscle fibres?
Fasciculi.
What is the outer sheath of a bundle of muscles fibres?
Perimysium.
What is the name of the membrane around each muscle fibre?
Endomysium.
Individual muscle fibre are formed from what structure?
Rod-like.
What mechanism result in muscles contraction?
The sliding filament mechanism.
What are the two types of myofilaments?
Actin and myosin.
What is the name given to the compartments that myofilaments are arranged in?
Sarcomeres.
Describe a tendon and its attachments.
Tendon: tough, inelastic fibres which wrap around the end of the muscles and attached to the outer layer of the bone.
Which are the thin and which are the thick myofilaments?
Actin – thin
Myosin - thick
Which structure attaches to the actin filaments and pulls on these filaments?
A series of ‘hook like’ projections referred to as myosin heads.
Why is calcium important to muscle contraction?
Myosin binding sites on the actin are blocked by a combination of other molecules (troponin and tropomyosin) that must be moved before myosin can be attached. Calcium causes the blocking molecule to move away from the binding site, thus allowing the ‘primed’ myosin head to bind with the actin.
Describe the location and function of the sarcoplasmic reticulum.
Surrounding the myofibrils is a network of tubes called the sarcoplasmic reticulum (SR) that act as calcium reservoirs.
Identify the three types of muscle fibre.
- Type I: slow twitch fibres
- Type IIa: intermediate twitch fibres
- Type IIb: fast twitch fibres
Which muscle fibre type is the most associated with long-duration, aerobic activities?
Type I: slow twitch fibres.
Which muscle fibre type is very anaerobic in nature?
Type IIb: fast twitch fibres.
Which type of muscle fibre will take more slow twitch or fast twitch characteristics depending on the training stimulus?
Type IIa: intermediate twitch fibres
What is the term for soreness experience in muscles one to three days after exercise?
Delayed onset muscle soreness (DOMS).
Which axis of movement is generally associated with the sagittal plane of movement?
The medial-lateral axis.
Which plane of movement is generally associated with the longitudinal axis of movement?
The transverse plane.
List the joint action and planes of movement available at the shoulder joint.
Flexion – extension
Abduction – adduction
Internal – external rotation
List the joint actions, planes of movement and axes of movement available at the ankle joint.
Joint action = plantarflexion – dorsiflexion
Plane of movement = sagittal
Axis of movement = medial - lateral
Name the muscles of the rotator cuff.
- Teres minor
- Supraspinatus
- Infraspinatus
- Subscapularis
The shoulder girdle is comprised of what bony structures?
Scapulae and clavicles.
Name four muscles of the shoulder girdle.
- Rhomboid major
- Rhomboid minor
- Levator scapulae
- Trapezius