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From the era before Sanger sequencing was invented.


7h
comment Why is too much glucose harmful?
An excellent answer - it really should be accepted.
10h
comment “Same” DNA vs genes
Repeat of biology.stackexchange.com/questions/9172/…
2d
comment Why is too much glucose harmful?
Perhaps worth adding that the level of glycated haemoglobin is used as a way of monitoring how well diabetes is being controlled over the long term.
2d
comment Why is too much glucose harmful?
This answer has things backwards. In diabetes the failure of the insulin response to high blood sugar means that the glucose carriers are not recruited to the cell membranes. This results in a decreased capacity for glucose uptake and so blood sugar stays high. Also, glucose does not "oxidise itself".
Jul
17
comment Why doesn't honey spoil quickly?
see biology.stackexchange.com/questions/19744/…
Jul
14
comment Turning publicly available genome data into proteins
I think that you need to be more specific than "I downloaded a complete human genome". Was this an entire genome sequence, or a set of FASTA sequences corresponding to predicted proteins?
Jul
11
comment How big can cold-blooded animals get?
Wikipedia en.wikipedia.org/wiki/Physiology_of_dinosaurs#Metabolism looks like a good place to start.
Jul
11
comment The move from RNA to DNA and the necessity of reverse transcriptase
You may be interested in the paper here: jbc.org/content/275/33/25523.full.pdf . The authors find that single mutations in an RNA-directed RNA polymerase can reduce selectivity for an NTP substrate to the point that there is no significant preference for NTPs over dNTPs. However this comes at the cost of very much reduced rate of polymerisation.
Jul
11
comment The move from RNA to DNA and the necessity of reverse transcriptase
This argument seems to be very circular. In an RNA world there presumably wouldn't be any DNA polymerase at all - what we should be looking for is an enzyme that can make DNA using an RNA template - which is a reverse transcriptase. The key step in the evolution of such an enzyme would be switching from polymerising NTPs to polymerising dNTPs.
Jul
11
comment The move from RNA to DNA and the necessity of reverse transcriptase
@Chris yes, apologies for the ambiguity, OP asserts that standard DNA polymerase can use RNA template, but I would like to see the evidence for this.
Jul
11
comment The move from RNA to DNA and the necessity of reverse transcriptase
Could you give a reference for standard DNA polymerases using an RNA template?
Jul
11
comment Significance of synthesis of D-glucose in plants..?
@Chris has explained the advantage of using one isomer - why do you think that it would be advantageous to synthesise and use both?
Jul
10
comment Will a vasectomy prevent genetic engineering of a child?
DNA from which cells?
Jul
5
comment A question about IPTG induction
@gucio I have expanded my answer - hope this helps.
Jul
2
comment What Proteins Are Universal To All Life Forms?
This answer was downvoted - I'd be really interested to hear why.
Jun
30
comment Theoretically, what technique would one use to modify a virus so that it only affected a subset of the population?
Also - there would be a strong selection for mutant viruses which gained the ability to recognise the receptor variant in the immune population.
Jun
29
comment How does the Cuttlefish camouflage itself accurately despite being color-blind?
@terdon I'm suggesting that there is no need to see the colours. If other (strictly non-visual) sensory inputs are an indicator of lying on a sandy surface then these could be used to promote the "correct" choice of colours.
Jun
28
comment How does the Cuttlefish camouflage itself accurately despite being color-blind?
Plants have evolved coloured flowers which they cannot see. Insect mimics have evolved patterns of colour which they cannot see. If the phenotype offers an advantage it can be selected for. Presumably cuttlefish can use other sensory cues to determine the nature of their surroundings and this information can be used as an input into the chromatophores and iridophores.
Jun
26
comment Essential amino acid codons
Perhaps worth adding that since most (all?) human initiation codons are AUG, most (all?) proteins contain an essential amino acid right there.
Jun
24
comment Can human change its morphology or anatomy due to ecological changes?
related question: biology.stackexchange.com/questions/8401/… Incidentally, Darwin was not awarded a knighthood.