Q: When the hydrogen is nearly used up, the star can fuse which element into heavier elements? Choices: - carbon - xenon - oxygen - helium A:
helium

Q: What area beneath the earth's surface do magma collects? Choices: - hot chambers - underneath chambers - erosion chambers - magma chambers A:
magma chambers

Q: Q: The nitrogen that enters living systems by nitrogen fixation is successively converted from organic nitrogen back into nitrogen gas by what? Choices: - algae - pollen - viruses - bacteria A:
A: bacteria

Question: Q: Chloroplasts are present only in cells of eukaryotes capable of what process? Choices: - hydrolysis - digestion - sexual reproduction - photosynthesis A:
Answer: photosynthesis

*Question*
Q: In gas exchange, oxygen flows into the blood, and what flows out? Choices: - naturally dioxide - carbon monoxide - liquid dioxide - carbon dioxide A:
**Answer**
carbon dioxide

*Question*
Q: How many pairs of upper jaws do insects have? Choices: - four pairs - six pairs - three pairs - two pairs A:
**Answer**
two pairs