Chapter 9 Muscles and Muscle Tissue Flashcards
Translations for muscle tissue specifically!
‘Mys’ or ‘myo’ or ‘sarco’ are for muscle tissue.
Cytoplasm is sarcoplasm
The plasma membrane is sarcolemma
Basic concepts for skeletal muscles?
Skeletal, striated, and voluntary. They are the longest.
Basic concepts for cardiac muscle?
Only found in heart. Remember cardiac, striated, involuntary.
Basic concepts for smooth muscle?
Found in walls of hollow visceral organs such as stomach, bladder and respiratory passages. No striations.
What are characteristics of muscle tissue?
Excitability - or responsiveness, ability to receive and respond to stimulus by changing membrane potential.
Contractility - can shorten forcibly
Extensibility - can extend or stretch even beyond resting length
Elasticity - ability to recoil and resume resting length after stretching.
What are the connective tissue sheets that cover muscle?
From the superficial to deep we have…
Epiymysium - dense irregular tissue surrounds the whole muscle
Perimysium - muscle fibers are grouped into fascicles and they are surrounded by this layer of dense irregular connective tissue.
Endomysium - each muscle fiber is surrounded by the loose areolar tissue of the endomysium. Just deep to this is the sarcolemma.
What are the two attachments points of muscle to bone called?
The Insertion where the muscle attaches more distally to a point which it will draw towards the…
Origin, the, typically, more proximal and less moveable sight of muscle attachment.
What are two types of attachment muscle can have with bone?
Indirect - muscle tissue connective wrappings extend beyond the muscle as tendons or aponeurosis.
Direct - the epimysium of the muscle is fused to periosteum of the bone or perichondrium of cartilage.
Two components found in the sarcoplasm in large quantities are?
Glycosomes - stored glycogen which can yield ATP
Myoglobin - stores oxygen similar to hemaglobin
What are myofibrils?
They are a chain of sarcomeres that run the entire length of the muscle fiber.
One fiber can contain hundreds to thousands and they account for 80% of cell volume.
What is the smallest contractile unit of a muscle cell?
A Sarcomere
What are thick filaments?
Myosin proteins anchored at M line
What are thin filament?
Actin proteins anchored at Z disc
