The right atrium receives blood returning from others parts of the body through the superior vena cava and the inferior vena cava.
Explanation:
The pathway of circulation begins in the right atrium which receives the carbon dioxide-rich deoxygenated blood returning through the systemic circulation.
The deoxygenated blood from regions superior to the heart, i.e., the head, neck, shoulder areas are collected through the superior vena cava and that from the parts inferior or lower to the heart like visceral organs, extremities, trunk, hip etc are brought through the inferior vena cava.
Both these venous systems (superior and inferior) fill the right atrium.
The right atrium then pumps the deoxygenated blood to the right ventricle via the tricuspid valve.
The right atrium is filled with blood during diastole.
<span>Deoxyribose is the same as ribose, except that the former has one more OH. DNAand RNA is the sugar, with 2-deoxyribose being replaced by the alternative pentosesugar ribose in RNA. The four bases found in DNA are adenine (abbreviated A), cytosine (C), guanine (G) and thymine (T).</span>
Answer: A. cooled and hardened lava from volcanoes
C. sediments deposited by rivers and ocean currents
An accretion is a process in which new materials are added to a tectonic plate or landmass. This process causes the enlargement of the landmass. The materials being added includes sediments, lava from volcanic eruptions and other materials from other sources.
The process of accretion can enlarge the size of a continent along its edge. The new land comes from the cooled and hardened lava from volcanoes and other reason is sediments deposited by rivers and ocean currents.