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A Lesson 2

4th grade Science

QuestionAnswer
fossil any evidence of an organism that lived in the past
fertilization joining together the female sex cell[the egg]with a male sex cell[the sperm],to produce a fertilized egg
mass extinctions when many different species die out at about the same time
extinct said of an organism no longer alive on earth
embryo a developing organism that results from fertilization
Created by: ammybear81