Chapter 4 Exercises

4.2) It is unlikely that the Martians died of viral infections because of the specificity of viruses. Viruses need to find a host cell with receptors compatible with it to attach. The host cell also must also have the capability to replicate the virus' genome and possibly synthesis and assemble capsids and other virus parts. If life on Mars developed independently from Earth, Martians would be extremely unlikely to have died from Earth viruses since their cells would not be compatible with the viruses.
4.3) a.) Orthologues b.) neither c.) Paralogues d.) Neither
4.7.) The antibiotic stremptomycin blocks protein synthesis in bacteria therefore it should also block mitochondrial and chloroplast protein synthesis, since mitochondria and chloroplasts are ancestors of bacterial organisms. According to the endosymbiotic theory, chloroplast and mitochondria were once free-living bacterial organism, which were phagocytosed and survived in their host cell as endosymbiotes. Ancestors of chloroploroplast are probably cyanobacteria and ancestors of mitochondria are alpha- protobacteria. Therefore the protein synthesis aparathus of mitochondria and chloroplasts is more similar to that of bacteria, which makes it sensitive to stremptomycin.
4.9) The lettuce sea slug could not let the chloroplasts reside in some body cavity because there would be no exposure to sunlight and the energy produced would have to be trasferred to the cells. The slug could use what little energy remains in the chloroplast, but with out exposure to sun the chloroplast would not produce addition energy for the slug. If the chloroplasts are endocytosed, they can be exposed to sun light and energy produced is given directly to the cells. Does any one else have any thoughts on this question?
4.10.) The diameter of the chromosome would be: 502336 nm or 0.502336 mm.  Since pii is equal to the circumference of a circle divided by the area, one can determine the diameter by dividing the circumference by pii. (4,639, 221 bp x 0.34 nm/bp)/ (3.14)
4.14) The goat and sheep seemt o have the largest number of functional globin genes and interestingly also have the fewest duplications.
4.15) Xenopus has had a triplication of the globin genes alpha and beta. The goat and sheep have had a triplication of the entire set of blobin genes (alpha through epsilon).
4.16) Mouse, goat , sheep and cow seem to have sigma-like psuedogenes. (I'm not totally sure on this one) 
 
Problems:
4.2) The New York Times article was mainly critical agains the thought of publishing the sequence of the influenza strain which caused a pandemic infection between years 1918-1919. One of the reasons agains publishing the sequence was its abuse by teroristic organisations. On the other hand publishing this sequence would benefit the progress in science.
4.6) The phylogenetic tree is arranged with the two different chimps sister to each other and next sister to humans because of the rearrangement on chromosome 2 (translocation).