Lecture Exam 2 Flashcards
(459 cards)
What are the 5 functions of skeletal muscles?
- Produce skeletal movement
- Maintain posture/body position
- Protect & support abdominopelvic cavity
- Regulate entering and exiting material
- Maintain body temperature
What 4 things is gross anatomy the study of?
- Muscle fibre organization
- Associated connective tissue
- Associated nerves
- Associated blood vessels
What 3 things is microscopic anatomy the study of?
- Myofibrils
- Myofilaments
- Sarcomeres
What are the 4 types of skeletal muscle fibre organization?
- Parallel (fusiform)
- Convergent (triangular)
- Circular (sphincteral)
- Pennate (featherlike)
Describe the parallel (fusiform) skeletal muscle organization.
Thick belly with tapered ends, fascicles run parallel to muscle axis and may run entire length of muscle
Describe convergent (triangular) skeletal muscle fibre organization.
A broad area that comes together at a common point; one portion of muscle can be stimulated at a time to change the direction of the pull
Describe the circular (sphincteral) skeletal muscle fibre organization.
A concentric ring that constricts an opening or orifice when contracting
Describe pennate (featherlike) skeletal fibre muscle organization. What are the 3 variations?
Fibres that form an oblique angle to the tendon of the muscle.
1. Unipennate
2. Bipennate
3. Multipennate
Describe each unipennate, bipennate, and multipennate skeletal muscle fibre organization.
Unipennate: fibres on the same side of tendon
Bipennate: fibres on both side of tendon
Multipennate: tendon branches within muscle
What are the 4 things tendons attach to?
- Bones
- Cartilage
- Ligaments
- Fascia
What is an aponeurosis?
A broad, flat tendon
What is the new terminology for the ‘origin’ of a muscle?
Axial skeleton: inferior attachment
Appendicular: proximal attachment
What is the new terminology for the ‘insertion’ of a muscle?
Axial: superior attachment
Appendicular: distal attachment
What are the two methods of describing muscle action?
- Reference to the associated bone region
- Reference to specific joint
Describe agonist, antagonist, and synergistic primary muscle actions
Agonist: prime mover; muscles for intended movement
Antag. muscle oppose intended movement
Syner. stabilizer; assist agonist
What does the term profundas mean?
deep
What does the term rectus mean?
Straight, parallel
What does the term caoitis mean?
Head
What does the term genio mean?
chin
What does the term palpebrae mean?
Eyelid
What are the 6 muscles of the mouth region of facial expression?
- Orbicularis oris m.
- Zygomaticus minor m.
- Zygomaticus major m.
- Buccinator m.
- Risorius m.
- Mentalis m.
What is the action of the orbicularis oris m.?
Compresses and purses lips
What is the action of the zygomaticus minor m.?
Retracts and elevates upper lip
What is the action of the zygomaticus major m.?
Retracts and elevates corner of mouth