Q: What phenomenon sometimes causes harmful alleles to become fixed? Choices: - natural selection - competition - spontaneous mutation - genetic drift A:
genetic drift

(Question)
Q: The complete combustion of alkanes to carbon dioxide is an extremely __________ reaction. Choices: - hydrolic - geothermal - reactive - exothermic A:
(Answer)
exothermic

Ques: Q: What does a healthy immune system fight off? Choices: - microorganisms and other dieases - respiratory and other dieases - bacteria and viruses - infections and other dieases A:
Ans: infections and other dieases

(Q).
Q: What is the name of plant-like protists? Choices: - sponge - arthropod - bacteria - algae A:
(A).
algae

Ques:Q: Polar molecules result from differences in electronegativity of what in the molecule? Choices: - ions - protons - iron - atoms A:

Ans:atoms

Ques: Q: What molecule is used for most energy functions in organisms? Choices: - DNA or deoxyribonucleic acid - RNA or ribonucleic acid - ADP or Adenosine Diphosphate - atp or adenozine triphosphate A:
Ans:
atp or adenozine triphosphate