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.
Diffusion vs. Active Transport: molecules move across cell membranes by two major processes diffusion or active transport. Diffusion is the movement from a high concentration of molecules to a low concentration of molecules. ... Moving molecules with cell energy is called active transport
They usually travel to warmer locatina to lay their egg. they burrow into the sand and lay their eggs
I guess so u can tell the difference :) <span />