PRACTICE TEST BANK 2026 TESTED
QUESTIONS AND ANSWERS GRADED A+
⩥ why is "selection" of bacteria and mutations used in the lab? Answer:
bacteria are grown in conditions that allow the mutated bacteria to
survive, while the wild type bacteria do not
⩥ How do scientists actually use selection of bacteria in the lab?
Answer: adding a resistance marker to the DNA plasmid that contains
the gene of intrest
⩥ What two ways are bacteria grown in lab Answer: liquid culture or
agar
⩥ Bacteria are usually grown in minimal medium, what does this mean?
Answer: medium that contains all the necessary organic compounds for
the bacteria to survive
⩥ Bacteria that can grow on minimal media are called: Answer:
prototrophic
⩥ What does being prototrophic mean? Answer: bacteria can grow with
no additional nutrients or reagents
, ⩥ what is the lag phase Answer: growth is very slow
⩥ what is log phase Answer: exponential growth
⩥ When bacteria reaches to ______________ in a culture, it will enter
stationary phase Answer: 1 million cells per ml
⩥ What is the stationary phase Answer: cease to grow
⩥ When will scientists harvest their bacteria Answer: log phase
⩥ define conjugation Answer: process of bacteria transferring genetic
information to another bacteria via direct contact
⩥ define auxotrophs Answer: bacteria strains that lack essential nutrients
so that they cannot grow without supplementation in the medium
⩥ Mixing two auxotrophs (needing different amino acids to grow) in the
same medium allowed them both to grow. How did this happen?
Answer: via conjugation and transfer of genetic material
⩥ "donor "bacteria are known as: Answer: F + cells