Excitation Of SA Node

P wave of ECG indicates 1. activation of SA node 2. depolarization of atrial muslces 3. spread of excitation froom AV node ot Purkinje fibres 4. repolarization of atria and depolarization of ventricles

Give the locations of S-A node and A-V node.

A : Elevated levels of Na^(+) increases the heart rate and contractility. R : Elevated Na^(+) level increase the excitability of SA node.

Function of SA node is

Lmpulse oritinating from SA node is transmitted to

A: In frog, sinus-venosus is present. R: In mammals and birds are remnant of sinus venosus has taken part in the formation of SA node.

Excitation Energy And Excitation Potential

Experiment Point |Nodes|Calculation Of Nodes|Exercise Questions|Summary

Assertion: SA node malfunctioning leads to disturbance of Heart rat Reason: SA node is the pacemaker of heart producing electric impulse for heart contraction