What was Rudolf Virchow’s contribution to the cell theory? He concluded that all cells come from preexisting cells.
He concluded that cells are the basic units of structure and function of all living things.
He concluded that all organisms are composed of cells.
He concluded that all cells are similar in composition and metabolic activities.

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.