Lecture 13 - Musculoskeletal system 3: Muscle Flashcards
What are 3 types of muscle tissue
- skeletal (striated, voluntary) aprox 40% body mass
- cardiac (striated, involuntary)
- smooth (visceral)(non-striated, involuntary)
What are 4 functions of muscles
- Movement: locomotion, manipulation, circulation)
- Stabilization of body position: gravity
- Regulation of organ volume: stomach, bladder
- Release of heat: during contraction
What are 4 characteristics of muscles
- Excitability or irritability: can transmit, produce & react to a stimulus (electric current, neurotransmitter)
- Contractility: shortening & widening of the cells ( force production, generated by an action potential)
- Extensibility: can be stretched
- Elasticity: retakes its form either after the contraction or the extension.
What is fascia
Connective tissue layer that covers muscles and organs
What is superficial fascia
(Under the skin)
Loose areolar CT and adipose tissue
What is Deep fascia
- dense CT
- surrounds deeper organs, including muscles
- makes strong fibrous framework
- bound to capsules, tendons, ligaments
What are other names for superficial fascia
Subcutaneous layer or hypodermis
What is subserous fascia
- betwn serous membrane and deep fascia
- areolar tissue
What are 3 layers of skeletal muscle
- Epimysium: envelopes all of the muscle
- Perimysium: surrounds the fascicles of myocytes 10-100
- Endomysium: isolate each myocyte
The epimysium and perimysium fuse and elongate to form
Part of the tendons
What is a tendon
- extension of CT
- interfaces with bone to produce strong anchor for contraction
What is aponeurosis
- broad flat sheet of CT
- typically merges with fibrous tissue from nearby muscle
What is tendon sheath
- double-walled tube that encloses tendons
- contains synovial membrane, reduces friction
What are the 6 type of muscle arrangements
- Parallel
- Fusiform
- Convergent
- Circular
- Spiral
- Pennate
Describe parallel muscle fibres arrangement
- long axis of the fascicles are oriented parallel to the long axis of the muscle
- straplike (ex. Sartorius / thigh muscle)