What is a long-term effect of the increased primary productivity of a terrestrial ecosystem?
a. the ecosystem will not be able to support as many tertiary consumers
b. it will decrease the amount of energy transferred to higher trophic levels
c. the ecosystem will be able to support more organisms at higher trophic levels
d. the ecosystem will become stagnant due to excess producers and organisms in higher trophic levels will die out

phylogenetic tree is the tree of life or evolution tree. it shows the different branches of evolution. the sequence goes like tissues - coelom - backbone - endoskeleton - segmentation

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.