Biology: Unit 1 and 2

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Across
  1. 3. record the collection of all the fossils discovered on Earth, providing a history of life on the planet
  2. 6. a relationship where one organism (hunter) hunts and kills another (prey) for food
  3. 7. world hypothesis RNA was the first carrier of genetic information due to its capacity to store genetic material and carry out reactions
  4. 9. ancestry the theory that all life forms descended from one "universal common ancestor"
  5. 11. the variety of species found in an ecosystem
  6. 15. the study of the geographic distribution of plants and animals, which provides evidence of common ancestry
  7. 16. homologies, structural similarities among different species because they descend from a common ancestor
  8. 18. a relationship where organisms fight for limited resources
  9. 19. long periods of little or no evolutionary change; can be seen in the fossil record
  10. 20. the theory that species evolve slowly and continuously over long periods of geological time
Down
  1. 1. cycle, a continuous cycle in which nitrogen circulates through living organisms and non-living components, including the atmosphere, soil, water, plants, animals, and bacteria
  2. 2. a symbiotic relationship where one organism benefits by harming the other (host)
  3. 4. cycle a continuous cycle in which carbon moves through the atmosphere, living organisms, oceans, and soil, shifting between inorganic and organic forms
  4. 5. a symbiotic relationship where one organism benefits while the other organism is unaffected
  5. 6. equilibrium the theory that species evolve in rapid, short bursts followed by stasis
  6. 8. factors, nonliving elements of the environment that influence the way that organisms and ecosystems function
  7. 10. a symbiotic relationship where both organisms benefit
  8. 12. homologies anatomical similarities in embryonic development among different species
  9. 13. factors, living components of the environment that affect the ecosystem or other living things in the environment
  10. 14. stability, the ability of an ecosystem to maintain balance and return to equilibrium after a disturbance
  11. 17. homologies similarities in genetic molecular structures (DNA, RNA, and protein) among different species