BIO1022 Lecture Notes - Lecture 7: Appendicular Skeleton, Neuromuscular Junction, Bone Marrow
6 Jun 2018
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Lecture 7 (17/8): Musculoskeletal System
Functions of muscles
· Maintenance of posture
· Movement within the body
· Peristalsis: movement of food through your gut
· Generation of heat and electricity: shivering
· Sound: the way we speak is determined by our diaphragm
· Internal organ function
· 4 major functional characteristics:
o Contractility
o Excitability
o Extensibility
o Elasticity
Types of invertebrate muscle
· Smooth
o Bivalve adductor muscle
· Striated (stripes)
o Bivalve value closure muscle
· Fibrillar muscle
o Insect flight muscle
Vertebrate muscle tissues
· Skeletal
· Cardiac
· Smooth
Comparison of vertebrate muscle types
Document Summary
Peristalsis: movement of food through your gut. Sound: the way we speak is determined by our diaphragm. 4 major functional characteristics: contractility, excitability, extensibility, elasticity. Striated (stripes: bivalve value closure muscle. Muscle cross sectional area (how thick is the muscle because it relates to how much force it can apply. Mechanical advantage (ma) determined by relative position of fulcrum. Low ma low power but high speed (eg; bicep) High ma high power but low speed (eg; jaw) Muscle is attached to the bone by tendon. Sarcomere functional unit in geometric pattern of actin and myosin filaments. Muscle contracts when filaments slide towards each other. For muscle contraction, atp and calcium must be present. Skeletal muscles innervated by motor neurons from spinal cord. Motor unit is neuron and fibres it innervates (few to 2000) They provide support holding the body together. Individual bones made up of bone tissue, marrow, cartilage and periosteum.
