29 Questions
Where do axons leave the central nervous system?
via spinal nerves and cranial nerves
What is the result of the sliding filament theory of contraction?
Muscle contraction
What is the role of calcium in muscle contraction?
To expose binding sites on actin
What is a muscle twitch?
A brief contraction followed by relaxation
What is a characteristic of fast muscle fibers?
Large fibers for great strength of contraction
What is the purpose of the troponin-tropomyosin complex?
To facilitate muscle contraction
What occurs in an isometric muscle contraction?
The muscle length remains constant while tension increases
What is the definition of an isotonic contraction?
A contraction where muscle shortens with approximation of the ends
What is muscle tone?
The amount of tautness that remains in a muscle at rest
What is an example of an isometric contraction?
Pushing against a wall without moving
What is the definition of work in muscle contractions?
Force multiplied by distance
What is the purpose of the skeletal muscle load tension diagram?
To represent the relationship between load and tension
What is the primary function of the more extensive blood vessel system and capillaries in slow muscle fibers?
To support high levels of oxidative metabolism
What characterizes fast muscle fibers?
Large amounts of glycolytic enzymes and fewer mitochondria
What is the primary function of myoglobin in slow muscle fibers?
To store oxygen for rapid contraction
What is the difference between fast and slow muscle fibers in terms of innervation?
Fast muscle fibers are innervated by larger nerve fibers, while slow muscle fibers are innervated by smaller nerve fibers
What is the definition of the force exerted on an object by a contracting muscle?
Tension
What is the primary cause of muscle fatigue?
Depletion of muscle glycogen
At what frequency of stimulation do successive contractions eventually become so rapid that they fuse together?
100 stimuli per second
What occurs when the frequency of stimulation is increased, leading to partial addition of the second contraction to the first?
Frequency summation
What is the term for the state of muscle contraction when successive contractions become so rapid that they fuse together?
Tetanization
What is the result of prolonged and strong contraction of a muscle?
Muscle fatigue
What is the state of muscle contraction when individual twitch contractions occur one after another?
Unfused tetanus
What is the outcome of delivering a series of maximal stimuli to skeletal muscle at a frequency just below the tetanizing frequency?
An increase in the tension developed during each twitch until a plateau is reached
What is the primary difference between summation and tetanus?
Summation is the addition of individual twitch contractions, while tetanus is a sustained muscle contraction
What is the advantages of motor unit recruitment in multiple fiber summation?
It allows for the gradation of muscle force in small steps during weak contractions
What is the outcome of frequency summation?
An increase in muscle force, leading to tetanization
What is the primary mechanism of multiple fiber summation?
Increasing the number of motor units contracting simultaneously
What is the characteristic of the first muscle fibers recruited during multiple fiber summation?
They have high resistance to fatigue
This quiz covers the transmission of nerve impulses into muscle contraction, the sliding filament theory, and the role of actin and myosin in skeletal muscle contraction.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
