Which of the following nitrogen bases is not found in the rna structure?
a. adenine
c. guanine
b. cytosine
d. thymine

Where substance is produced during cellular respiration

Why did mendel use pea plants in his experiments? a. they have no alleles. b. they are haploid organisms. c. they reproduce quickly. d. they are all male.

There are fewer than 100 naturally occurring elements in the universe, but there are millions of different unified substances. explain how this can be true.