I believe that the best answer to the choices given in your question is<span>Viruses have to infect a living cell in order to reproduce</span> Thank you for posting here at Brainly.I hope I have answered your question. Have a nice day ahead.
Viruses are the microorganisms who needs to infect the living host cells, in order to replicate or reproduce. These infectious agents are capable of injecting and infecting all the life forms present, including the plants, animals and bacteria. The viruses were not among the first organisms to evolve as in order to replicate themselves and continue through the time they needed other organisms' cell.
Hence, the correct answer is 'viruses have to infect a living cell in order to reproduce'.
The answer is granzymes. are serine proteases which trigger the apoptotic cascade in target cells. Apoptotic enzymes activated by granzymes can also destroy viruses or other cytoplasmic pathogens in the target cells so that the pathogens cannot infect nearby cells. Dead target cells are rapidly ingested by macrophages. The Tc cells also produce perforin pores to allow granzymes to enter the target cell.
Explanation: Electron microscopes are the most powerful type of microscope, capable of distinguishing even individual atoms. However, these microscopes cannot be used to image living cells because the electrons destroy the samples.
