Besides a high voltage shock, what is another method to make e. coli competent to take up "naked" dna?
a. high concentrations of calcium ions followed by high temperature
b. high concentrations of calcium ions and several hours on ice
c. large amounts of dna added directly to a bacterial culture growing at 37c
d. high concentrations of minerals followed by high temperature
e. a high voltage shock is the only way to make e. coli competent

the correct answer is c   with the systems

1. b.

2. d.

3. a.

5. d.

6. c.

these are the only ones that i know, i hope this , and good luck.

the species living around the vents are especially good at dispersal.  

deep-sea vent originates on the floor of the ocean when seawater circulates through hot volcanic rocks, usually situated where the new oceanic crust is being produced.  

biological dispersal refers to the movement of species from their location of birth to their site of breeding, or from breeding site to another. similarly, the oceanic dispersal refers to the movement of the species from one land mass to another by sea crossing.