Ques:Q: What produces almost one-half of the earth's oxygen through photosynthesis? Choices: - prokaryotes - algae - arthropods - protists A:

Ans:protists
-----
Ques:Q: What "kind" of water may take longer to become contaminated than surface water, while the natural cleaning process may take longer? Choices: - lake water - spring water - dam water - groundwater A:

Ans:groundwater
-----
Ques:Q: The secondary wall contains _________ , a secondary cell component in plant cells that have completed cell growth/expansion. Choices: - cytoplasm - glucogen - cellulose - lignin A:

Ans:lignin
-----
Ques:Q: Fermat's principle states that light will always take the path of least amount of? Choices: - energy - momentum - resistance - time A:

Ans:
time
-----