CELL

CELL


define cell

DEFINE CELL

 

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Define Heartbeat ?

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HEARTBEAT ➤ The alternating  relaxations and contractions make up the cardiac cycle and one   complete  cardiac cycle makes one heartbeat.and in other words, one complete pulsation  of the heart  is called heartbeat. It is the complete regular movement movement of our  heart as it passes  blood around your body. STEPS OF CARDIAC CYCLE ➤ C omplete cardiac cycle consist of the following steps .   CARDIAC DIASTOLE ➤ Atria and ventricles relax and blood is filled in atria. this period is called cardiac   diastole.  In short, it is the period of relaxation of heart muscles.In one complete heartbeat,   diastole  lasts about 0.4 seconds. ATRIAL SYSTOLE ➤ It is the last phase in diastole during which the ventricular filling is  competed.    Immediately  after their  filling, both atria contracts and pump blood towards ventricles.   This period in  cardiac cycle is called  atrial systole.In o...
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