Answer the following question given this paragraph: Q: What phenomenon sometimes causes harmful alleles to become fixed? Choices: - natural selection - competition - spontaneous mutation - genetic drift A:
genetic drift
(Question)
Answer the following question given this paragraph: Each step in the process is either a gain of oxygen or a loss of hydrogen. Each step also releases energy, which explains why the complete combustion of alkanes to carbon dioxide is an extremely exothermic reaction. Q: The complete combustion of alkanes to carbon dioxide is an extremely __________ reaction. Choices: - hydrolic - geothermal - reactive - exothermic A:
(Answer)
exothermic
Ques: Answer the following question given this paragraph: Eat well, get enough sleep, and be active every day. These healthy lifestyle choices will help keep your immune system healthy so it can fight off respiratory infections and other diseases. 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).
Answer the following question given this paragraph: Plant-like protists are called algae (singular, alga). They are a large and diverse group. Some algae, diatoms, are single-celled. Others, such as seaweed, are multicellular (see Figure below ). Q: What is the name of plant-like protists? Choices: - sponge - arthropod - bacteria - algae A:
(A).
algae
Ques:Answer the following question given this paragraph: Polar molecules result from differences in electronegativity of the atoms in the molecule. Q: Polar molecules result from differences in electronegativity of what in the molecule? Choices: - ions - protons - iron - atoms A:

Ans:atoms
Ques: Answer the following question given this paragraph: All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. Endothermic reactions absorb energy, and exothermic reactions release energy. 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