Choose the correct option for $A , B$ and $C$
Auto-Rhythmicity of Heart
Automatic rhythmicity of the heart is the ability to contract spontaneously, Mammalian heart is myogenic. It means heart beat results from a wave of electrical potential called cardiac impulse arising from sinoatrial node $SA$ node and spreading over cardiac chambers.
$SA-$node lies in the wall of right atrium near opening of superior vena cava and contract about $72$ times per minute. Form $SA$ node cardiac impulse travels to atrioventricular node (lies between right atrium and ventricle)
Then pass to $AV$ bundle (also called bundle to His) and its branches reaches to the Purkinje fibres in ventricles.
Bundle of His provides the only route for the transmission of wave of excitation from atria to ventricles. Purkinje fibres conducts the impulses five times more rapidly than surrounding cells. It forms a pathway for conduction of impulse that ensures that the heart muscle contracts in the most efficient manner
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Statement $I$: Mitochondria and chloroplasts both double membranes bound organelles.
Statement $II$: Inner membrane of mitochondria is relatively less permeable, as compared chloroplast.
In the light of the above statements, choose the mis appropriate answer from the options given below: