Which is the best definition of a prokaryotic cell?

it has a cell wall but lacks a well–defined nucleus and organelles, and its cytoplasm doesn't have much structure.
it contains a membrane–bound nucleus and organelles, and its organelles have specialized duties.
it contains a membrane–bound nucleus, a large central vacuole, a cell wall, a cell membrane, and chloroplasts.

Which of the following observation darwin shape his concept of descent with modification? a) species diversity declines farther from the equator. b) fewer species live on islands than on the nearest continents. c) birds live on islands located farther from the mainland than the bird's maximum nonstop flight distance. d) south american temperate plants are more similar to the tropical plants of south america than to the temperate plants of europe. e) earthquakes reshape life by causing mass extinctions.