What would be the advantage of restriction enzymes producing sticky ends in recombinant DNA technology than blunt ends?
Thanks!
Sticky ends provide a greater surface area for bonds to occur and DNA to hybridise. Blunt ends can only form covalent, phosphodiester bonds where as sticky ends can form both covalent
and hydrogen bonds with a foreign DNA sample. Also, as DNA ligase is needed to anabolise the backbone of DNA, using sticky ends will be quicker too (I guess?) because DNA ligase would work more efficiently (the two DNA strands would have already hybridised due to hydrogen bonds, therefore successful collisions between the enzyme and recombinant DNA would occur more frequently). I've gone a bit chemistry, but that might help clear things up?
Chimpanzees are the closest living relative to modern humans (98% of our genomes are similar). Explain in terms of natural selection, how the two species diverged
Thank you all
Okay, so firstly you'll need to consider the principles of natural selection:
-variation of phenotypes present within a population (clines; occur by chance) prior to exposure to selection pressure.
-struggle for survival due to selection pressures (abiotic and biotic)
-selective advantage (favourable phenotypes)
-inheritance (individuals with selected phenotypes reproduce, therefore passing on favoured genes to their offspring)
-frequency of selected phenotypes thus increases within a population (microevolution)
So, when answering the question you'll need to address these principles.
An example of an answer may be:
The divergence would have occurred due to their common ancestor inhabiting different areas and therefore exposing itself different selection pressures. Due to the phenotypic variation within the species, different traits would have been selected for in these different environments. The favoured traits would have then been passed on via inheritance, increasing the frequency of their alleles within the population. This example of microevolution would have eventually resulted in speciation when the gene pools of both groups became isolated so that successful interbreeding could not occur.
My answer is verbose ahah but I think it covers the question