4. Nitrogen gas is more abundant in our atmosphere than oxygen! However, nitrogen needs to be
converted into different forms to be used by many
organisms. Bacteria are highly involved in this!
Describe the role of (A) bacteria fixing nitrogen as
they live symbiotically with some plant species, (B)
nitrifying bacteria, and (C) denitrifying bacteria in
the nitrogen cycle.

Modern whales developed their traits through natural selection what occurs during the process of natural selection

The graph shows the amount of global warming happening in different ecosystems. which populations of organisms will likely decline the most as a result of climate change, and why? a.coral reefs because of the loss of the symbiotic algae living within their bodies b.penguin populations because the fish they eat will move into warmer waters c.mountain-dwelling birds because rising sea levels will relocate their food sources d.large cats in the rainforest because of decreased habitat loss for their prey

Which of the following is the earliest era of earth's geologic time scale? cenozoic mesozoic precambrian paleozoic