When heart is not pumping sufficient blood according to needs of body organs n it leads to heart failure. Lung congestion is main symptom of heart failure.

Serum is composed of plasma which is devoid of clotting factors. Normally, plasma contains 6-8% of proteins and 90-92% of water. It also contains minerals, biomolecules and clotting factors.

The average cardiac output of a healthy adult is 5000ml or 5 liters. This means that if heart rate is 72 beats per minute and stroke volume is 70ml, n around 5000ml of blood is pumped by each ventricle in one minute.

By counting number of QRS complexes that occur in a given period, one can determine heartbeat rate of an individual. Any deviation from shapes of curve indicates a possible abnormality or a disease. Hence, it is of great clinical significance.

A successful blood transfusion takes place only when blood groups of donor and recipient are compatible. When blood groups are not compatible, it results in destruction of RBCs.

In joint diastole state, all four chambers of heart are relaxed. The tricuspid and bicuspid valves are open while semilunar valves are closed. Blood from pulmonary vein flows into left ventricle.

The muscular heart is located in thoracic cavity of body. It is located on ventral side of body. The stomach, kidneys and ovaries are located below heart and lungs.

Fibrinogens are needed for clotting or coagulation of blood. Globulins primarily are involved in defence mechanisms of body and albumins help in osmotic balance.

When a Rh-negative mor produces antibodies to an antigen in blood of a Rh-positive fetus, it leads to a condition known as erythroblastosis fetalis. It can be avoided by administering anti-Rh antibodies to mor.

The relaxation of atria or atrial diastole coincides with contraction of ventricles or ventricular systole. The right and left semilunar valves open up due to increase in pressure in ventricles.