B.
because the radioactive decay continues until a stable isotope is formed.
Answer:
Diffusion in the Lungs trades out Carbon Dioxide (CO2) for Oxygen (O2) In the Circulatory system it trades Oxygen (O2) for Carbon Dioxide (CO2)
Explanation:
As you breathe the Lungs take in air, as they do that the air travels to the bronchi, from there it goes through a process where the veins which have carried de-oxygenated blood to be diffused and reloaded with Oxygen and trade off their CO2. Then the blood flows through arteries and delivers the needed O2 to cells throughout the body and the cycle repeats.
Mrna and trna direct the cells to make the proteins needed out of amino acids
Fitness is the answer.
Evolution is the process of a species changing.
Mutation is also a species changing.
Variation is the differences between animals of the same species.