What is an important difference between the biosynthesis of purine nucleotides and pyrimidine nucleotides?

a. the growing pyrimidine ring is bonded to ribose while the ribose is added later to the purine ring.
b. purine nucleotides require n10- in their biosynthetic pathways.
c. the growing purine ring is bonded to ribose while the ribose is added later to the pyrimidine ring.
d. proline is the precursor for purine biosynthesis while it is not for pyrimidine biosynthesis.

Indicate whether the following statements about the biases in the fossil record are true or false. a) inland species are more likely to be preserved than marine species b) organisms with hard body parts are more likely to be preserved than are those composed soft tissues. c) species that existed over a larger area are more likely to be preserved than species existing over a smaller area. d) organisms that lived very long ago are more likely to be found as fossils than organisms that lived relatively recently e) the fossils of larger organisms are more likely to be found than the fossils of smaller organisms

Select the best answer for the question, ly 12. which of the following behaviors is not an inherited behavior?

The greenhouse effect a. something that has occurred for millions of years b. an unnatural phenomenon caused by humans that maintains earths temperature range. c. the results of the differences in the angle of the suns rays d. an unnatural phenomenon that causes heat energy to be radiated back into the atmosphere