Muscles Flashcards
What are the three types of muscles?
Skelteal muscle
Cardiac muscle
Smooth muscle
Smooth muscle
Involuntary muscle
Occurs in the walls of the digestive tract, uterus and blood vessels
Un - striated
Cardiac muscle
Involuntary muscles
Occurs in the heart
Striated
Skeletal muscle
Voluntary muscle
Usually attached to bones via tendons
Striated
What are the characteristic of muscle tissue?
Excitability or responsiveness
Contractility
Extensibilty
Elasticity
What are the role of the muscles?
Movement
Posture and position
Generate heat
STabilise joints
What are the features in the structure of the skeletal muscle?
Epimysium
Perimysium
Fascicles
Endomysium
Anatomy of skeletal muscle fibres
Sacroplasmic reticulm T - tubule Sarcoplasm Triad Terminal cistena
Features of myofibrils
Myofibrils are bundled into muscle fibres and surrounded by sarcolemma
Rod - like contractile elements that occupy most of the muscle fibre cell volume
Myofibrils are composed of sarcomeres arranged end to end
This banding gives the muscle its striated or striped appearance
Features of a sarcomere
Myosin Actin I - band A - band H zone M line Z- disk
What is Tropomyosin?
Rod shaped, stabilises actin, in relaxed muscle they block myosin binding sites on actin
What is Troponin?
Globular shaped, binds calcium released by the occurenece of an action potential, an d modified the position of tropomyosin to allow for myosin binding
