A bacterium produces a toxic metabolic by-product that it needs to efflux to the environment against the toxin's concentration g
radient. The energy to drive this efflux comes from the electrochemically favorable influx of protons. This is an example of Select one:
a. ABC transport.
b. antiport.
c. symport.
d. facilitated diffusion.
Differentiation occurs numerous times during the development of a multicellular organism as it changes from a simple zygote to a complex system of tissues and cell types.
