Across
- 2. an extreme example of genetic drift that happens when the size of a population is severely reduced
- 4. a very simple microorganism that infects cells and may cause disease
- 7. organisms whose cells contain a nucleus and other membrane-bound organelles
- 8. asexual reproduction by a separation of the body into two new bodies
- 11. small single-celled organisms
- 12. type of structural modification made to a part of the body
- 16. when different organisms independently evolve similar traits
- 17. choosing parents with particular characteristics to breed together and produce offspring with more desirable characteristics
- 19. the process through which populations of living organisms adapt and change
- 20. the complete disappearance of a species from Earth
Down
- 1. a branch of science that is related to the formation, growth, and development of embryo
- 3. the direct transfer of DNA between two cells that are temporarily joined
- 5. When two organisms create a third organism through reproduction
- 6. a feature that a species inherited from an ancestor but that is now less elaborate and functional than in the ancestor
- 9. the process by which individuals compete for access to mates and fertilization opportunities
- 10. process within evolution that leads to the formation of new
- 13. one parent copies itself to form a genetically identical offspring
- 14. cases where two (or more) species reciprocally affect each other's evolution
- 15. matching genes
- 18. mechanisms of gene transfer from one population to another