Killer flu strains arise from recombination of human strains with those of pigs, ducks, and chickens monkeys cattle rhinoviruses bacteriophages 33. If any part of statement is false, put B 34. Some lichens may live to be greater than 3000 years old 35. Normal prion proteins are produced by all healthy humans, and function as an outer coating of nerve cells 37. Cannibals in New Guinea would have avoided catching Kuru by first cooking the brains of their enemies.
All viruses have a nucleic acid, protein capsid, and an outer lipid bilayer.
Bacteria usually make us sick by releasing toxins rather than by taking over cells like viruses. Protista is probably the most difficult kingdom for taxonomists, and it is likely that it will eventually be divided into several separate kingdoms having little in common. Cyanobacteria are common in lichens 44. The HIV virus attacks Killer T cells, cells which switch on other parts of the immune system 45. Mutations in HIV occur nearly every time it replicates, thus it can evade the body's immune response and resistance to drugs may also arise very quickly 46.