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Title: In an experiment, the strength of a neural stimulus and the resulting muscle contraction are ... Post by: rachelle17 on Dec 21, 2016 o contract a single muscle fibre, the same all-or-none response occurs. Then, how is it possible to lift a heavier object? When lifting a heavier weight, more muscle fibres are stimulated. To lift a smaller weight, fewer muscles fibres are stimulated.
In an experiment, the strength of a neural stimulus and the resulting muscle contraction are compared. A single motor neuron that synapses with one muscle fibre is observed in this experiment. One end of the muscle fibre is attached to a mass. If an electrical stimulus is sufficient to cause an impulse in the neuron, the muscle will contract and lift the mass. The following data were obtained from the experiment. Analyze the data, and answer the following questions. Number of Trials Strength of stimulus (mV) Mass lifted by muscle contraction (g) 1 10 0 2 20 0 3 30 20 4 40 Not Tested 1.What is threshold potential? In this experiment, what is the threshold potential for this motor neuron? 2.What is all-or-none principle? What mass can be lifted at 40 mV stimulus? Title: Re: In an experiment, the strength of a neural stimulus and the resulting muscle contraction are ... Post by: rachelle17 on Jan 15, 2017 Someone please help!
Title: Re: In an experiment, the strength of a neural stimulus and the resulting muscle contraction are ... Post by: psyche360 on Jan 15, 2017 Hi Rachelle, see if this helps!
Title: Re: In an experiment, the strength of a neural stimulus and the resulting muscle contraction are ... Post by: rachelle17 on Jan 15, 2017 There are no answers to the questions I need!
Title: Re: In an experiment, the strength of a neural stimulus and the resulting muscle contraction are ... Post by: habiba on Jan 15, 2017 The all-or-none law is the principle that the strength by which a nerve or muscle fiber responds to a stimulus is independent of the strength of the stimulus. If that stimulus exceeds the threshold potential, the nerve or muscle fiber will give a complete response; otherwise, there is no response.
Title: Re: In an experiment, the strength of a neural stimulus and the resulting muscle contraction are ... Post by: habiba on Jan 15, 2017 Most have the answers except for the ones you need :o
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