BMS129 Lecture Notes - Lecture 2: Epimysium, Pronator Teres Muscle, Palmar Interossei Muscles
MUSCLE
Lecture 2 - Structural & functional organisation of muscles
1. Describe the varied functions of muscles
2. List & describe the connective tissue coverings of a muscle
3. List & describe the various shapes of skeletal muscles with examples for each
and relate to function
4. Explain the terms origin, insertion, belly and action of a muscle
5. Explain the different functional roles of muscles (e.g. prime mover, agonist,
synergist, antagonist & fixator) using elbow joint flexion as an example
6. Explain the terms intrinsic and extrinsic in relation to muscles
Describe the varied functions of muscles
- Movement
- Maintenance of posture
- Stabilise joints to prevent unwanted movement
- Communication through speech, writing and expression
- Heat production through shivering
List & describe the connective tissue coverings of a muscle
1. Epimysium
Covers whole muscle belly
Blends into CT between muscles
2. Perimysium
Slightly thicker layer of connective tissue
Surrounds bundle of cells called a fascicle
3. Endomysium
Thin sleeve of loose CT
Surrounds each muscle fibre
4. Deep facia
Between adjacent muscles and surrounding muscle groups
Helps hold muscles with similar functions together
5. Superficial fascia (hypodermis)
Predominantly adipose tissue between skin and deep fascia around muscles
List & describe the various shapes of skeletal muscles with examples for each
and relate to function
Shape
Example
Function
Fusiform
Biceps brachii
Thick in middle and
tapered at ends
Parallel
Rectus abdominis
Consists of long muscle
lengths and hence allow
for increased range of
Document Summary
List & describe the connective tissue coverings of a muscle: epimysium. Surrounds bundle of cells called a fascicle: endomysium. Helps hold muscles with similar functions together: superficial fascia (hypodermis) Predominantly adipose tissue between skin and deep fascia around muscles. List & describe the various shapes of skeletal muscles with examples for each and relate to function. Consists of long muscle lengths and hence allow for increased range of motion. Broad at origin and major and deltoid tapering to a narrower insertion. Multiple actions to be produced by the same muscle due to differences in fibre direction within the muscle mass. Force production more onto one side of tendon muscle fibres able to be (e. g. palmar interossei and packed into a given hands and feet) cross-sectional area. Bipennate: fibres insert onto a tendon from opposite sides like a feather (e. g. rectus femoris in thigh)
