What are the receiving chambers of the heart and what are the discharging chambers?

The receiving chambers are the right and left atria and the discharging chambers are the right and left ventricles separated by a septum.

The heart has four chambers: two atria and two ventricles . The right atrium receives oxygen-poor blood from the body and pumps it to the right ventricle. The right ventricle pumps the oxygen-poor blood to the lungs where they are oxygenated. The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle.

So, the pattern goes like:

RA ----> RV ---> Lungs ----> LA ----> LV

Source: http://www.webmd.com/heart/chambers-of-the-heart