Species - A group of organisms that interbreed and produce fertile offspring. population - A group of organisms of the same species living in the same area at the same time, and which are capable of interbreeding. community - A group of populations living and interacting with each other in a common habitat.
Chargaff's rules state that DNA from any cell of all organisms should have a 1:1 ratio of pyrimidine and purine bases and, more specifically, that the amount of guanine is equal to cytosine and the amount of adenine is equal to thymine .
Krebs cycle xxxxxxxxxxxxx'xxxxxx
the complementary DNA sequence can be read out by replacing each base with its complement and reversing the order.<span> The complementary base pairs are A to T and G to C, so every G is replaced with a C and so on.</span>
