I think it's 420,000 kcal, because 10% of energy is lost as you move up each trophic level. To find what you started with you would multiply by 10 instead of dividing by 10. You have to multiply by 10 twice, because of the primary consumers and producers.
I believe this is a bit of a trick question, while you are right about both B and D, they both preexist they just develop into other structures. I believe the correct answer is A since the nerve cord is hollow not solid.
<u>Answer:</u>
<em>The true statement concerning complex multi-cellular organism is Bulk transport systems move substances faster than simple diffusion.</em>
<u>Explanation:</u>
<em>Bulk transport</em> is the mechanism that is used by the cells to transport the large quantity of small and tiny molecules and particles. Bulk transport works on the <em>mechanism of pressure gradient and single diffusion</em> is based on the concentration gradient.
The<em> transportation on single diffusion</em> is due to random motion of molecules but in bulk transport the solute and water is moved <em>together and in a faster pace. </em>
The statement that best describes the difference between a gene and an allele is that a section of DNA that usually contains the code for a specific protein that determines a specific trait is a gene, while an allele is a section of a gene. The correct option among all the options that are given in the question is the last option or option "D".
