NEETZoologyBody Fluids and Circulation
What happens to the ventricular muscles during ventricular systole?
Options
- AThey relax
- BThey contract
- CThey remain unchanged
- DThey fluctuate
Correct answer
B. They contract
Step-by-step solution
The SAN now generates an action potential which stimulates both the atria to undergo a simultaneous contraction – the atrial systole. This increases the flow of blood into the ventricles by about 30 per cent. The action potential is conducted to the ventricular side by the AVN and AV bundle from where the bundle of His transmits it through the entire ventricular musculature. This causes the ventricular muscles to contract, (ventricular systole), the atria undergoes relaxation (diastole), coinciding with the ventric