it is the fluid filled space between the axon terminal and the sarcolemma
100
What is muscle tone?
Constant, slightly contracted state of all muscles
100
what is hyperplasia
when smooth muscle cells can divide and increase numbers
as oppose to in size
200
what is the plasma membrane for muscle cell called?
Sarcolemma
200
What are the four functions of muscles?
Movement of bones or fluids (e.g., blood)
Maintaining posture and body position
Stabilizing joints
Heat generation (especially skeletal muscle)
200
Is sodium more abundant inside or ourside a resting cells plasma membrane
outside
200
what is isometric contraction?
no shortening; muscle tension increases but does not exceed load
200
What is peristalsis
Alternating contractions and relaxations of smooth muscle layers that mix and squeeze substances through lumen of hollow organs
300
What are the three pre fixes that indicate that you are taling about muscles?
Myo, mys, and sarco
300
What is a cross bridge?
when myosin heads bind to actin
300
what are tropomyosin and troponin
regulatory proteins bound to actin
300
what is isotonic contraction ?
muscle shortens because muscle tension exceeds load
300
what are the two layers represented in smooth muscle?
Longitudinal layer
Circular layer
400
what is the contractile unit of muscle called?
sarcomere
400
Name 3 the connective tissue sheaths of skeletal muscle tissue from external to internal
Epimysium, Perimysium, Endomysium
400
What are the 4 special characteristics of muscles?
Excitability (responsiveness): ability to receive and respond to stimuli
Contractility: ability to shorten forcibly when stimulated
Extensibility: ability to be stretched
Elasticity: ability to recoil to resting length
400
What does a motor unit consist of?
Motor unit = motor neuron and all muscle fibers it supplies
400
what does the overload principle basically state?
increase use promotes muscle gains
500
what is the sarcoplasmic reticulum?
Functions in regulation of intracellular Ca2+ levels
Stores and releases Ca2+
500
what is acetylcholinesterase
An enzyme that breaks down ACh to acetic acid and choline
Prevents continued muscle fiber contraction in absence of additional stimulation
500
In what two places in the process of muscle contraction is calcium necessary?
calcium causes the exocytosis of ACh an the NMJ
calcium causes a conformational change in the Tropomyosin and troponin which are the regulatory proteins bound to actin
500
What percentage of of energy released in muscle activity useful as work
40%
500
define muscle hypertrophy
Due primarily to increase in fiber size
Due primarily to increase in cell size as apposed to increasing cell number