Delivering single shocks in succession to stimulate the frog heart . Delivering single shocks in succession to stimulate the frog heart . did not increase the height of the ventricular systole wave resulted in wave summation resulted in fused tetanus increased the height of the ventricular systole wave.

Question:

Delivering single shocks in succession to stimulate the frog heart .

A) resulted in wave summation

B) resulted in fused tetanus

C) increased the height  of the ventricular systole wave

D) did not increase the height of the ventricular systole wave

The correct answer is D). The Shocks didn't increase the height of the ventricular systole wave.

Explanation:

The above is an experiment carried out on a frog. Not just on the frog but on is ventricule.

The experiment was carried out delivering electrical stimuli on the ventricles at different points:

1. when it was pulsating and

2. when it was contracting or relaxing.

During the first part of the of the contraction until nearly maximum, simulation didn't have any effect at all. This period is known as the Refractory Period.  

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