Answer:
with each heartbeat,the heart pumps blood throughout our bodies,carrying oxygen to every cell,after delivering oxygen the blood returns to the heart the heart then sends the blood to the lungs to pick up more oxygen.
Answer:
The human body uses 21 amino acids to make the proteins it needs to function.
Evolution of a species acts on the population of the species
Explanation:
Rust is the term we use to describe red iron oxides produced when ferrous metals corrode. Rust is the common name for the chemicals that result when iron reacts with oxygen and water. “Rust” is poorly defined in chemistry, however—lots of chemicals can be formed when iron is left exposed.