input: OPTIONS:
- oxygen gradient
- speed gradient
- solution gradient
- temperature gradient Now, answer this question: Q: A change in temperature with distance is called a what? A:
A:
output: temperature gradient

Q: What makes up most of the interior of a plant? A:

OPTIONS:
- conjunction tissue
- support tissue
- transport tissue
- ground tissue

Answer: ground tissue

Problem: OPTIONS:
- crystal regia
- acidus regia
- sulfate regia
- aqua regia
Q: Q: What a mixture of nitric acid and hydrochloric acid? A:
Answer: aqua regia

Problem:OPTIONS:
- gravitational
- astronomical
- biological
- physical

Q: What properties describe the existence of matter, as opposed to chemical properties that describe how substances change into other substances? A:
****
A: physical

Q: What element is essential for amino acid and nucleic acid production? A:
OPTIONS:
- oxygen
- carbon
- hydrogen
- nitrogen
nitrogen

Q: What are all of the living or once-living aspects of the environment called? A:
OPTIONS:
- abiotic factors
- photic factors
- fossils
- biotic factors

Answer:
biotic factors