The superior vena cava is located in the upper chest region and is formed by the joining of the brachiocephalic veins. These veins drain blood from the upper body regions including the head, neck, and chest. It is bordered by heart structures such as the aorta and pulmonary artery.
The superior vena cava (and inferior vena cava) are veins that return deoxygenated blood from circulation in the body and empty it into the right atrium.
Animals get protein from diet.
<h3><u>Explanation:</u></h3>
Proteins are one of the important part of diet which constitute about one fifth of an ideal diet. This proteins are formed of amino acids. There are 20 amino acids in nature, of which 9 are essential amino acids and 11 are non essential amino acids. The non essential amino acids are prepared in our body by enzymes. But the essential amino acids are needed to be supplied from outside via diet to get access to. So proteins are needed to be present in diet.
