Histo 2 skeletal muscle and nerve tissue Flashcards
Key features of skeletal muscle
What is the arrangement/ orginization of cells in muscle?
Muscle cell
Fascicle
What is a muscle comprised of?
Where are the nucleus located in muscle fibers?
On the edges
What is myosin made of?
what is myosin attached to?
and by what?
What is actin made up of?
what determines its length?
what makes up functional part of actin?
components of a sarcomere?
Muscle contraction
Sarcoplasmic reticulum releases Ca. Ca binds the troponin. causing a shift in tropomyosin. Actin binding sites accesible to myosin heads
in contraction what gets closer together?
what slides on what?
Does anything shorten or lengthen?
What are the types of skeletal muscle?
how do they differ?
parts that are part of the electrical impulse in muscle
What is a triad made up of?
T tubule + 2 terminal cisternae (1 on each side)
connected by end feet
Triad
What is skeletal muscle innervated by?
a-motor neurons from the anterior horn of the spinal cord
The neuromuscular junction
How many nerves innervate muscle fibers?
Neuromuscular junction to contraction?
Acetylcholine released bind sodium channel. this causes signal to be relayed down sarcolemma until it reaches a T-tubule
neuromuscular junctions
explain the reflexive response to overstretching of a muscle
neuromuscular spindle apparatus
- intrafusal muscle fibers overstretched.
- Type 1a fibers sense the stretch
- A-motor and G-motor neurons receive signal from 1a and cause muscle to shorten
What type of muscle fiber contract the muscle?
what type senses length and rate of change?
Extrafusal muscle fibers
Intrafusal muscle fibers
What are type 1a sensory nerve fibers?
what are a-motor and g-motor?
