Because we have carbon in the ground in the air and every were else
Since the other answer got deleted, i'll just answer it for you.
a sinoatrial node is the main pacemaker that begins each heartbeat located in the junctions of superior vena cava and the right atrium. It signals from the node that spread through the atria and determines the heart rates.
Answer:
Metaphase 1: Microtubules of one pole are attached to kinetochores of one of the two chromosomes facing to the same pole. Metaphase 2: Microtubules are attached to the kinetochores of the centromere on either side of a single chromosome
Explanation:
<span>If a person has type B blood, only anti-A antibodies are present in his or her blood.</span>
Inheritance is the process by which traits are passed from the parents to their offspring. The basic unit of inheritance in human is the DNA. For traits to be passed from the parent to the offspring, the DNA in the cell must be duplicated and this happens through the process of cellular reproduction.