Genome
...concept of "the word" in the very beginning of the earth. The word Ridley refers to is genomic information stored in RNA molecules. Long has debate continued about which came first, the DNA that codes for protein or the proteins that catalyze chemical reactions. Ridley suggests that RNA came first, with its ability to copy itself without assistance. The first chromosome contains a gene that is suspected as being the first gene, able to duplicate itself for it is repeated on the first chromosome over and over again.
Terms: ur-gene': probably the very first gene, able o duplicate itself and therefore catalyze reactions using chemicals around it. May have been made of RNA.
ribo-organism': before any other organism, Ridley suggests that RNA began to evolve into larger organisms that paved the way for life.
LUCA': Last Universal Common Ancestor, or first sophisticated organisms that stored its genetic code on DNA, a more stable convention, made its enzymes of proteins and used RNA to intermediate the two.
Questions: Is it in the nature of RNA to utilize reverse transcriptase and form DNA, or did this happen by mutation or other modes of evolution?
What about the chemical make-up of RNA empowers it to replicate itself?
How does bacteria acquire genes by ingesting other bacteria?
CH 2-
Ridley uses chromosome 2 to illustrate the subtle distinction between species, especially man and chimpanzee. Both Chimpanzees and gorillas have 24 pairs chromosome. Humans have only 23 because our second chromosome is the product of a fusion between two medium-sized ape chromosomes. That is why it is the second largest in our collection. Notwithstanding our ecological success, and the many apparent discrepancies between humans and chimps, we are ninety-eight percent chimp and they are ninety-eight percent human. Which means the two species share all but two percent...
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