Ribosomes are to the RER as: water towers are to firefighters.
tires are to a car.
gas stations are to a highway.
ling
propellers are to a helicopter.

Which of the following is the best definition of a eukaryota? a. a one-celled organism that does not have a membrane-bound nucleus b. a one-celled organism that does not have a cell wall c. an organism whose cells each contain a membrane-bound nucleus d. an organism whose cells each have a cell wall