Nitrifying bacteria participate in the nitrogen cycle mainly by(A) converting nitrogen gas to ammonia.(B) releasing ammonium from organic compounds, thusreturning it to the soil.(C) converting ammonium to nitrate, which plants absorb.(D) incorporating nitrogen into amino acids and organiccompounds

Question 9 In a nutrient spiral, __________________.     A)  nutrients are transported to deeper waters.   B)  nutrients are transported downstream.   C)  salmon move nutrients to terrestrial systems.   D)  nutrient cycles occur in discrete segments of the stream.     Question 10  _________ obtain energy from inorganic molecules; _______ obtain energy from organic molecules.     Autotrophs; heterotrophs   Heterotrophs; autotrophs   Secondary consumers; primary producers   Carnivores; photosynthesizers

Which of the following staements about evoulution is true?  A) Evoulution is deliberate and purposeful B) Indivduals envolve within the span of their lifetimes C) Oranisms evolve structures in response to needs D) Evoulution can result in adaptations Which of the following lists contains only polysaccharides? A) Fructose, cellulose, and glucose B) Starch, amino acids, and glycogen C) Celloulose, starch, and glycogen D)Sucrose, starch, and cellulose

Why are nitrogen-fixing bacteria ecologically important? Why are humans interested in nitrogen-fixing bacteria? (Economic applications?)