Could you be more specific? 90 percent of the energy in what?
<span>Superior and inferior vena cava enters the right atrium which is pumped by the tricuspid valve to the right ventricle and to the pulmonary valve to the pulmonary artery then to the lungs from the lungs back thru the pulmonary veins entering the left atrium pumped by the mitral valve to the left ventricle to the aortic valve to the aorta.
The circulatory system is important in meeting the needs of all cells in the body because it offers means of transport by which cells obtain the materials needed to live and function.</span>
Flatworms have no need for circulatory and respiratory systems because they are able to actively diffuse oxygen through their skin and their body layout is such that they do not need to transport oxygen in order for it to get to their cells.
Helicase molecules is active first in DNA replication. DNA helicase are enzymes capable of unwinding duplex DNA to provide the single- stranded DNA templates that are required in processes such as replication and recombination.all helicase separates the strands double mix helix using energy derived from hydrolysis nucleotide.
Answer:
D) it helps scientists create theories which are universal.
