These protocells became the first unicellular life forms. Unicellular life
forms then gave rise to life forms as cells began to specialize in function. These are the hypothesized sequence of events in early history
of life on earth. These steps are speculative but still scientific because
they are rooted in logic, firm science, and testable hypotheses.
a. multicellular
b. cell membrane
c. polymers
d. biomolecules