Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 18786
TLS Online TPP Program

#Question id: 1077

Would ID50 and LD50 necessarily be the same for a given virus? Why or why not?

#XL - T Zoology

  1. Yes, because the number of viruses that infect 50% of a test population should also kill 50% of that test population.

  2. No, because a virus may be highly infectious (very low ID50 value) but only marginally lethal (very high LD50 value). A prime example of this is the rhinovirus (common cold virus).

  3. No, because very few viruses are lethal, yet many are highly infectious. The two values should ALWAYS be different.

  4. Yes, because what we're actually describing here is infection/killing of individual CELLS, not of entire organisms. If a cell is infected, it will always be killed.

More Questions
TLS Online TPP Program

#Question id: 12157

#XL - R Botany

Which of the following statements concerning protists is false?
TLS Online TPP Program

#Question id: 2185

#XL - S Microbiology

Which amino acids would most likely reside in the membrane-anchoring domain of a membrane-embedded protein?
TLS Online TPP Program

#Question id: 11162

#XL - S Microbiology

Which statement represents the best explanation for the observation that the nuclear DNA of wolves and domestic dogs has a very high degree of homology?
TLS Online TPP Program

#Question id: 1778

#XL - Q Biochemistry

Which is not a function of IgG?
TLS Online TPP Program

#Question id: 8917

#XL - R Botany

The Hox genes came to regulate each of the following in what sequence, from earliest to most recent?
1. identity and position of paired appendages in protostome embryos
2. formation of water channels in sponges
3. anterior-posterior orientation of segments in protostome embryos
4. positioning of tentacles in cnidarians
5. anterior-posterior orientation in vertebrate embryos