How might the presence of life on another planet be inferred from the composition of that planet's atmosphere?
What will be an ideal response?
Detection of a gas or series of gases at a level which cannot exist outside the influence of biology would be indicative of life. The best example of this is if high concentrations of CH4 and O2 were discovered on a planet. Because O2 and CH4 are highly reactive, this would require high fluxes of both gases. The required fluxes are higher than abiogenic fluxes of these gases. Thus, the detection of both of these gases at significant levels is indicative of a biosphere.
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A cow is an example of a grazer. Indicate whether the statement is true or false
An "air mass" is a large body of air that has similar horizontal characteristics of
A) moisture and temperature. B) temperature and density. C) density and pollen. D) moisture and winds.
How do many exotic species find their way to new waters?
A) Migrations B) Carried in the ballast water of tankers C) Marine birds D) None of these choices
Loam soil is primarily clay with small amounts of sand and silt.
Answer the following statement true (T) or false (F)