It would be 2) two atoms exchange electrons and become ions
DNA acts as a sort of set of instructions for building an organism.
In that way, different types of organisms--plants, animals, bacteria, etc.--can all be differentiated through their DNA because it is directly linked to how they function.
It helps to give solid evidence of natural selection. The idea is that there are a number of finches in the Galapagos Islands. These birds vary slightly in appearance, in the function of their beaks and in size. Two species can eventually alter themselves because of the environmental conditions they live in. Some traits will be passed on or developed in one group and not in the other or vica versa. These finches are remarkable in that it did not take long for the changes to take place. It is probably one of the strongest reasons for believing in natural selection, because only those birds who could adapt to change could easily pass on these advantages to their offspring. The relatively short period of time to enact these changes is what makes the this example so attractive.
Earth's service would be bare. There would no longer be life and all water ways would become dried up due to the intense ultra-violent rays of the sun.
Answer:
Arteries
Explanation:
There are three main types of blood vessels: veins, arteries, and capillaries. Arteries are the blood vessels that carry the oxygenated blood from the heart to various body parts. Veins pick the deoxygenated blood and deliver it to the heart to be oxygenated.
Arteries are the blood vessels with thick walls and no valves. Blood is pumped with higher pressure from the heart into arteries. The pulmonary artery is the only exception that carries deoxygenated blood from the right ventricle to the lungs for oxygenation.