The Rise of Kâ12 Blended Learning | 133 NSTITUTE NNOSIGHT represents a ranking of 1 st in Santa Clara County and 5 th in California when compared to similar schools with at least 70 percent low-income students.
The heart has four chambers, two upper atria, the receiving chambers, and two lower ventricles, the discharging chambers. The atria open into the ventricles via the atrioventricular valves, present in the atrioventricular septum. This distinction is visible also on the surface of the heart as the coronary sulcus.
It's about the size of a person's fist. The heart has four chambers. The upper two chambers are the atria, and the lower two are the ventricles (Figure A). The chambers are separated by a wall of tissue called the septum. Blood is pumped through the chambers, aided by four heart valves. The valves open and close to let the blood flow in only one direction.