How is nitrogen returned to the atmosphere during the nitrogen cycle?

a.
it is returned to the atmosphere in a process called nitrogen fixation.
b.
it is returned to the atmosphere through denitrification.
c.
it is returned to the atmosphere through cellular respiration.
d.
it is returned to the atmosphere through evapotranspiration.

Sampling lake water for microscopic organisms is not as easy as it sounds when you want to both count and identify species. in a given water sample, your bacteria of choice can be rare or difficult to culture, particularly given the mixture of bacteria in a biofilm. which of the following culture media would be best for growing fecal coliforms when they are relatively less abundant than other bacteria in the lake? anaerobic culture medium enrichment culture medium complex culture medium basic culture medium

When listening the levels of orginization in orginisims from the smallest to most complex , which level is just below organs in complexity

How do you think earths interior affects what is happening on the surface? 2. how do fossils support the continental drift hypothesis? 3. how does sea- floor spreading support the hypothesis of continental drift? 4.what do scientists observe when they studied the magnetic fields of rocks on the sides of mid-ocean ridges? 5. what is a tectonic plate ? 6. explain mantle convection 7.how can movements of the continents affect earths climate? 8. what occurs during drifting?