Chapter 9 Flashcards
Fill in the blanks
Skeletal muscle is a _ _ muscle usually attached to bones
skeletal muscle is a voluntary striated muscle usually attached to bones
Muscles have long slender cells, what are these called?
muscle fibres
What is muscular tissue used for?
movement, stability of the body, control of body passages and openings, heat production
Muscle cells are able to carry out….
excitability, conductivity, contractility, extensibility + elasticity
Match the following up
Origin & insertion
stationary end & moving end
Stationary end + origin
moving end + insertion
fill in the blanks
Muscle fibers are long and slender cells they have multiple _ just inside the _.
Muscle fibers are long and slender cells they have multiple nuclei just inside the sarcolemma.
Fill in the blanks
The sarcoplasm is accompanied by _ which are thread like bundles of _ _.
The sarcoplasm is accompanied by myofibrils which are thread like bundles of protein filaments.
What are myofibrils?
Myofibrils are bundles of protein myofilaments
What are thick filaments made up of?
myosin
What are thin filaments made up of?
actin
What is contractility?
skeletal muscle contracts only when stimulated by a somatic motor neuron
What is it called when nerves and muscle fibers meet at a complex of synapses?
neuromuscular junction
What separates the synaptic knob from the sarcolemma?
synaptic cleft
What is a synaptic knob?
it contains synaptic vesicles filled with the chemical ACh.
What terminates the stimulation of muscle fibers?
An enzyme called acetylcholinesterase found in the synaptic cleft as part of the sarcolemma breaks down the ACh which terminates the stimulation of muscle fibers.
How is smooth muscle different from skeletal muscle?
- not under voluntary control
- slow sustained contractions
- much smaller muscle fibers
- does not have striations
- a different type of myosin exists in smooth muscle called multiunit
The wave like motion of many tubular organs known as peristalsis is caused by what sort of muscles?
visceral smooth muscles
Smooth muscle is affected by the a neurotransmitter, what is it called?
norepinephrine
Which is slower to contract, smooth or skeletal muscle?
Smooth, 30x slower
How much slower is smooth muscle than skeletal muscle?
30x
Which requires less energy, smooth or skeletal muscle?
smooth
What regulates smooth muscle contraction?(3)
nerves, hormones + local chemical changes
