Tagged Questions
0
votes
1answer
43 views
Plants without bacteria? is it theoretically possible?
I know from school, that all live on the Earth need bacteria as low-level "machines" that break down/extract/convert/produce chemical elements and combinations, other high-level organisms needed. But ...
14
votes
2answers
915 views
Why is glucose our primary source of energy?
Is there any evolutionary reason for glucose being the "main" molecule used as a source of energy, beginning with glycolysis and subsequently cellular respiration (after being converted to two ...
15
votes
4answers
706 views
Why are there exactly four nucleobases in DNA?
Does someone know why DNA is composed of four nucleobases? In particular, is there an explanation for the number? Why four and not two, or eight?
19
votes
1answer
183 views
Evolutionary origin and exogenous cues of ~28 day infradian rhythm?
The most obvious example of an approximately monthly biological cycle is the human menstrual cycle. My questions are the following:
Is it known when and where this cycle or one like it arose?
What ...
28
votes
4answers
2k views
Why 20 amino acids instead of 64?
This question got me thinking about amino acids and the ambiguity in the genetic code. With 4 nucleotides in RNA and 3 per codon, there are 64 codons. However, these 64 codons only code for 20 amino ...
