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Zorluk: OrtaIdentifying Hypotheses and Beliefs

Martian Soil Activity Models

During the 1976 Viking Lander missions, scientists observed chemical activity when Martian soil samples were mixed with a liquid nutrient solution. Two scientists proposed competing hypotheses to explain this observation.

*Scientist 1*
The soil activity is biological. Martian soil contains microscopic organisms that metabolize organic nutrients. When these organisms consume the nutrients, they release carbon dioxide (CO2CO_2) gas. Heating the soil to 160C160^\circ\text{C} kills these organisms, which is why preheating the soil prevents gas release.

*Scientist 2*
The soil activity is inorganic. Highly reactive oxygen-carrying chemicals, such as superoxides, are present in the soil due to exposure to intense ultraviolet radiation. When mixed with the liquid solution, these superoxides chemically oxidize the nutrients, releasing CO2CO_2. Heating the soil to 160C160^\circ\text{C} thermally decomposes the superoxides, rendering them unable to react with nutrients.

According to Scientist 1's hypothesis, what is the primary agent responsible for the release of carbon dioxide gas from the soil mixture?

  1. Living microorganisms that consume and metabolize the nutrientsCevap
  2. B
    Reactive inorganic superoxides that chemically oxidize the nutrients
  3. C
    Ultraviolet radiation that directly decomposes the organic compounds in the solution
  4. D
    Thermal decomposition of nutrients caused by preheating the mixture to 160C160^\circ\text{C}

Cevap

Living microorganisms that consume and metabolize the nutrients
Scientist 1's hypothesis states that Martian soil contains microscopic organisms that metabolize organic nutrients, and their consumption of these nutrients releases carbon dioxide gas.

Adım Adım Çözüm

1
Locate the hypothesis of Scientist 1 in the passage.
Scientist 1 asserts that the soil activity is biological, involving microscopic organisms.
This identifies which scientist's viewpoint is being tested.
2
Identify what Scientist 1 states is the cause of the gas release.
Scientist 1 states that the microscopic organisms metabolize (consume) organic nutrients and release carbon dioxide gas.
This directly answers what agent is responsible for the gas release according to Scientist 1.

Anahtar Kavram

Identifying the specific mechanisms and agents proposed in a scientific hypothesis.
Tahmini Süre:1m 30s
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