Question

valves preventing the backflow of blood. It resu
heart sound known as Lub. As the ventricular
semilunar valves guarding the pulmonary artery an
allows the blood in the ventricles to flow into
circulatory pathway
Cardiac diastole
The ventricles now relax and the ventricular
of the semilunar valves which prevents the back
production of the second heart sound known as I
declines further, the AV valves are pushed open
by the blood, which flowed into them through the
again flows freely into the ventricles. All the h
relaxed state (joint diastolic phase). Soon, anoth
Explain the mechanism of clotting of blood
Blood clotting takes place in three essential steps
i. Step - 1: It involves the formation of a
collectively called, prothrombin activator
of chemical reactions that occur in the blood by
in two pathways.
a. Intrinsic pathway: It occurs when the blo
wall of blood vessel. This activates Faeton
clotting factor, which activates yet anothe
results in the formation of the prothrom
b. Extrinsic pathway : It occurs when th
vascular tissue comes into contact with​

Answer 1

Answer:

gvhjjj. uhf chhunch hhhbbnkklinmk

Answer 2

Answer:

veins have thin walls because the blood there is no longer under pressure and it have valves which prevents the backflow of blood which prevents mixing of oxygenated and deoxygenated blood.