It depends on the rate at which the heart beats. It will be faster during physical activities, and slower when sleeping, for example.
The vessel that brings blood back to the right atrium is the superior vena cava and the inferior vena cava.
The most fetal blood in the umbilical vein enters the inferior vena cava through the ductus venosus.
The Inferior vena cava - just like the Superior vena cava -, returns blood to the heart. When blood is returning to the heart, that blood is already circulated in the body, therefore it is already downloaded the oxygen to the body tissues, and picked up the carbon dioxide from them. From the vena cava (superior and inferior), the blood enters the heart (right atrium), is pumped into the right ventricle, and then pumped into the lungs (through the Pulmonary Arteries), where carbon dioxide is exchanged for oxygen. So, the blood in the vena cava is deoxygenated.
Blood is returned to the heart via the vena cava, specifically the superior vena cava from the upper body and the inferior vena cava from the lower body.
venous system, specifically the femoral veins and the popliteal vein. Blood then flows up through the inferior vena cava to the heart.
Through Superior vena cava & inferior vena cava . The blood from anterior part of the body is taken to heart through superior vena cava,the blood from posterior part of the body is taken through inferior vena cava.
The most fetal blood in the umbilical vein enters the inferior vena cava through the ductus venosus.
The vessel that brings blood back to the right atrium is the superior vena cava and the inferior vena cava.
the inferior vena cava caries de-oxygenated blood.
Superior Vena Cava and the Inferior Vena Cava
The inferior vena cava is the largest vein, and connects to the right atrium of the heart. The other large vein is the superior vena cava, which receives blood from the upper half of the body.
Either through the Superior Vena Cava located at the superior aspect of the heart, through the Coronary Sinus located at the inferior aspect of the heart, or through the Inferior Vena Cava located at the inferior aspect of the heart. All of these drain into the right atrium.
The Inferior vena cava - just like the Superior vena cava -, returns blood to the heart. When blood is returning to the heart, that blood is already circulated in the body, therefore it is already downloaded the oxygen to the body tissues, and picked up the carbon dioxide from them. From the vena cava (superior and inferior), the blood enters the heart (right atrium), is pumped into the right ventricle, and then pumped into the lungs (through the Pulmonary Arteries), where carbon dioxide is exchanged for oxygen. So, the blood in the vena cava is deoxygenated.
Vena Cava.
Inferior vena cava
Blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium.
The inferior vena cava is the major vein which carries the blood into the heart from the lower half of the body.