Discharge from muscle spindles could be increased by all the following, except :-a- increased α-motor neuron dischargeb- increased γ-motor neuron dischargec- stretch of the intrafusal muscle fibersd- stretch of the extrafusal muscle fibers
Q: In your own words, describe the main events occurring between the arrivalof an action potential at a…
A: The chemical synapse that favors the transmission of the signal from the motor neurons to the muscle…
Q: γ-motor neuron discharge to a muscle is inhibited by impulses reaching the γ-motor neurons from all…
A: A gamma motor neuron cell bodies are located in the anterior grey column of the spinal cord. A gamma…
Q: Explain in detail: 1) how an action potential occurs in a lower motor neuron, 2) how the motor…
A: Action Potential --- Propagation of information in the nervous system from central nervous system…
Q: 3. Activation of Golgi tendon organ of a given muscle: a- Activates motor neurons that return to the…
A: *The Golgi tendon organ also called as neurotendinous spindle which is a proprioceptor that was a a…
Q: Type I fibers are only recruited in light repetitive movements like postural adjustment and slow…
A: The muscle fibres have a specialised structure that helps in contraction. Usually the actin and…
Q: If implanted electrodes were used to stimulate action potentials in gamma motor neurons to flexors…
A: When gamma motor neurons are activated, the striated ends of a muscle fiber are stimulated, thus…
Q: When a higher voltage is applied to the skeletal muscle, the force of contraction _____ and…
A: Skeletal muscle fibres has the ability to cause muscle contraction if it encounters an appropriate…
Q: What special characteristics of the presynaptic neuron (motor neuron) and motor end-plate…
A: The neuromuscular junction (NMJ) is the site for chemical interaction between the motor neuron and…
Q: Co-activation of α and γ-motor neurons :-a- increases γ-motor neuron discharge whenever the…
A: Alpha (α) motor neurons control muscle contraction involved in voluntary movement, whereas gamma (γ)…
Q: Describe the general anatomical design of a muscle spindle and discuss its physiological function.
A: Muscle spindles are a special type of sensory receptors (proprioceptors) present inside the muscle…
Q: The role of γ-motor neurons in regulation of equilibrium is achieved by :-a- initiating…
A: The nervous system plays a major role in transmitting the reflexes from the tissues to the brain.…
Q: Define the all-or-none principle.
A: According to All-Or-None principle, When threshold stimulus is applied to a neuron then it will…
Q: Which role do gamma (γ) motor neurons play in the function of a muscle spindle? Select one: a.…
A: Gamma motor neurons work in muscle contraction and represent 30 percent of the group A nerve fibers…
Q: Why does a person with muscles that have a higher percentage of slow fibers have greater endurance…
A: In humans muscles constitute about 40 to 50 percent of the total body weight. These muscles are…
Q: γ-motor neurons control muscle tone by :-a- adjusting the supraspinal facilitatory dischargeb-…
A: Muscle tone refers to the maintenance of partial contraction which important for maintaining posture…
Q: In flexor withdrawal reflexes contraction of flexor muscles is associated with reciprocal…
A: Withdrawal reflex is a postsynaptic occurring in response to a noxious stimuli. Characterised by…
Q: Describe the functions of gamma motor neurons and explain why they are stimulated at the same time…
A: The gamma motor neurons innervate the muscle spindle at every finish. they permit contraction of the…
Q: Describe motor control in terms of the conceptual motor control hierarchy. Use the following terms:…
A: The axon terminals of the many neurons junction on a motor neuron at intervals in the brain stem or…
Q: Match the component of the neuromuscular junction with the correct terminology. v somatic motor…
A: Neurons are the nerve cells in the human nervous system. The neurons can transmit nerve signals from…
Q: Explain why muscle tone is first decreased and then increased when descending motor tracts…
A: The fibre tracts that carry impulses from the brain to the skeletal muscles are called "motor or…
Q: In the stretch reflex,a. Golgi tendon organs activate contraction in extrafusal muscle…
A: A stretch reflex occurs when muscles are stretched, and the receptors send action potentials up the…
Q: Increased γ-motor neuron discharge stimulates muscle spindles, because :-a- it produces stretch of…
A: A gamma motor neuron (γ motor neuron) is a type of lower motor neuron, which takes part in the…
Q: In general, fast-twitch fibers generate less power than slow-twitch fibers. A. True B. False
A: People have two general types of skeletal muscle fibers: slow-twitch (type I) and fast-twitch (type…
Q: 41- Gamma motor neurons: a- Causes contraction of the equatorial region of an intrafusal fiber b-…
A: The mechanism of gamma motor neurons helps in regulating muscle length and tone.
Q: Which of the following would be recruited in a muscle stimulation when contractile strength…
A: Small motor units, typically consisting of one nerve and a few muscle cells, are recruited first.
Q: Fasciculations of lower motor neuron lesions :-a- are caused by injury currents initiated in the…
A: The brain is the most important part of the body that controls every action in our body. It is a…
Q: Label the patellar reflex arc and reciprocal innervation in Figure .
A: Sensory organ Sensory neuron Interneuron Cell bodies of motor neuron Motor neuron Motor neuron…
Q: C. The single muscle twitch. Duration of latent period O 012 = % of total twitch time sec % Duration…
A: Twitch:- Muscle contractions, also known as fasciculations, are small, involuntary muscle…
Q: The nuclear-bag fibers of muscle spindles are innervated by :-a- Aγ nerve fibersb- Aβ nerve fibersc-…
A: The muscle spindles are stretch receptors inside the body of a muscle. The reflexes are immediate or…
Q: How is the prolonged refractory period generated incardiac muscle? What is the advantage of a…
A: The absolute refractory period is a kind of duration of time that occurs after the starting of the…
Q: What do we mean by the somatic motor system? O a. Cardiac muscle O b. The smooth muscles and glands…
A: Introduction : The group of central and peripheral nervous system elements that support motor…
Q: 38- Which of the following is not a characteristic of the muscle spindles: a- Encapsulated…
A: Muscle spindles: it is belongs to proprioceptors.
Q: a. At what time point did would a nerve begin to fatigue? Comment on the percentage decrease in…
A: Introduction Muscle fatigue:- It is a decrease in maximal force or power production in response to…
Q: Using pyramidal motor tract as a template, describe the voluntary control of skeletal muscles being…
A: Pyramidal tracts consist of the corticospinal tract and corticobulbar tract. The tracts are…
Q: When the γ-motor neuron discharge to a muscle decreases, it causes :-a- increased muscle spindle…
A: The nervous system plays a major role in transmitting the reflexes from the tissues to the brain.…
Q: Lower motor neuron lesions cause all the following, except :-a- decreased number of transmitter…
A: Lesion basically refers to the damage. Lower motor neuron lesion as the term suggests is the lesion/…
Q: The highly localized nature of stretch reflex is due to :-a- the limited number of interneurons in…
A: The spinal cord reflexes produced by central nervous system (CNS) pathways, which lie entirely…
Q: Interruption of spindle discharge from a muscle causes contraction of the muscle to become jerky and…
A: Muscle spindle is small, spindle-shaped sensory receptors located in skeletal muscle tissue and they…
Q: The fast fatigable motor units are used predominantly for which of the following activities?…
A: Fast fatigable motors are used when large forces for a short time are required.
Q: Explain how more than one smooth muscle cell can be influenced by an action potential generated in…
A: Explain how more than one smooth muscle cell can be influenced by an action potential generated in…
Q: Question B)
A: Pain occurs whenever tissues are being damaged, and it causes the individual to react to remove the…
Q: Concerning the cross-bridge (CB) power stroke, it is true that: O a. All of these O b. In concentric…
A: correct option is - B. in concentric contractions, the CB power stroke pulls the actin filament…
Q: Post-rotational alteration of muscle tone :-a- results from altered pattern of macular dischargeb-…
A: Muscle tone is the status of the contraction of the resting muscle. The partial contraction of the…
Q: Cell bodies of UMN that synapse on LMN lie in all of these areas EXCEPT a) Medulla b)…
A: Neurons are the structural and functional unit of the nervous system. A neuron sends and receives…
Q: The discharge from Golgi tendon organs initiated by excessive stretch ofa skeletal muscle produces…
A: Introduction Golgi tendon organ are the proprioceptor (sense organ) which receives the information…
Q: How would you modify this experiment so that the mass lifted by the muscle contraction continues to…
A: Muscle and nerve fibers add all or none principle. It implies that the strength of the stimulant…
Discharge from muscle spindles could be increased by all the following,
except :-
a- increased α-motor neuron discharge
b- increased γ-motor neuron discharge
c- stretch of the intrafusal muscle fibers
d- stretch of the extrafusal muscle fibers
Step by step
Solved in 2 steps
- Interruption of spindle discharge from a muscle causes contraction of the muscle to become jerky and irregular due to :-a- increased activity of reverberating circuits causing fluctuation of the motor discharge to the muscleb- increased activity of inhibitory interneurons causing oscillating inhibition of the α-motor neurons of the musclec- irregular discharge of excitatory inputs to the α-motor neurons of the muscle d- post-tetanic potentiation of the α-motor neurons of the muscleDescribe a muscle spindle and its function considering the following items. Use all terms in paragraph form to describe: - Extrafusal fibers - Intrafusal fibers - Alpha motor neurons - Gamma motor neurons - Capsule - Contraction - Afferent nerve fiber - Somatic reflex (as in the patellar reflex)Interruption of γ-motor neuron discharge to a skeletal muscle produces :-a- contraction of the muscleb- contraction of the spindle fibersc- relaxation of the spindle fibersd- increased sensory discharge from the spindle fibers
- Why is it important to remove acetylcholine from its binding to acetylcholine receptors once the neural stimulus ends? What can be the possible consequence of the non-removal of acetylcholine to the skeletal muscle fiber?Increased γ-motor neuron discharge stimulates muscle spindles, because :-a- it produces stretch of the extrafusal muscle fibersb- it causes stretch of the peripheral regions of the intrafusal fibersc- it causes stretch of the central region of the intrafusal fibersd- it stimulates directly the sensory fibers innervating muscle spindlesWhen the γ-motor neuron discharge to a muscle decreases, it causes :-a- increased muscle spindle dischargeb- shortening of the spindle fibersc- stronger contraction of the extrafusal muscle fibersd- decreased spindle sensitivity to stretch
- The discharge from Golgi tendon organs initiated by excessive stretch ofa skeletal muscle produces :-a- inhibition of α -motor neurons of antagonistic musclesb- inhibition of γ-motor neurons of antagonistic musclesc- inhibition of α -motor neurons of the same muscled- stimulation of γ-motor neurons of the same muscleWhen a cardica muscle is isolated and placed in a solution of sodium chloride, potassium chloride, and sodium bicarbonate, will muscle contraction occur if:a. muscle is stimulated directly by depolarizing the membrane? (provide a short explanation)b. muscle is stimulated by stimulating the nerve to the muscle? (provide a short explanation)We've referred to alpha-motor neurons as the "decision making centre" for whether or not a muscle fibre contracts. Which of the following statements are true with regards to his concept? Select all that apply. O Alpha motor neurons receive input from many different sources, the balance of which determines whether or not the alpha-motor neuron fires an action potential O Alpha motor neurons are involved in conscious decision making in our central nervous system for planning and executing movements O When an action potential is initiated in an alpha-motor neuron, we are guaranteed an action potential in the muscle fibre, and hence contraction of that fibre. This means the muscle itself does not determine whether or not it contracts O Alpha motor neurons report information on where we are in space (proprioception) back to the central nervous system
- *When dynamic y-motor neurons are activated at the same time as a-motor neurons to muscle, [A] prompt inhibition of discharge in spindle la afferents takes place. [B] clonus is likely to occur. [C] the muscle will not contract. [D] the number of impulses in spindle la afferents is smaller than when a discharge alone is increased. [E] the number of impulses in spindle la afferents is greater than when a discharge alone is increased.Succinylcholine act as adepolarising agent that prevents repolarization of the somatic motor neuron. Thus, no further ACh is released until drug is cleared. Name another site within the MNJ we could target to prevent muscle contraction, and explain why this would work.Muscle spindle structures consist of: Extrafusal muscle fibers and gamma motor neurons Extrafusal muscle fibers and alpha motor neurons Golgi tendon organs and gamma motor neurons Intrafusal muscle fibers and gamma motor neurons