Question: Q: What feature of the spine helps with flexibility and strength? Choices: - shape - angle - arrangement - curves A:
Answer: curves

Question: Q: What moves nitrogen back and forth between the atmosphere and organisms? Choices: - the calcium cycle - the Krebs cycle - the leakage cycle - the nitrogen cycle A:
Answer: the nitrogen cycle

Question: Q: What are solutions that maintain a relatively constant ph when an acid or a base is added? Choices: - gases - water - liquids - buffer A:
Answer:
buffer