What is the major source of nitrogen in the nitrogen biogeochemical cycle?

What is one reason that a certain percentage of land was preserved on islands such as Mauritius and Tobago during the 1700s when they were English and French colonies?

Which biogeochemical cycle is a slow cycle because the element is not found in gas form and because the main source is in rock formations, which take a long to make and to break down?

When describing the parts of a biogeochemical cycle the term “sink” refers to  

Scientific Consensus is often interpreted as “most scientists agree” however this is misleading because science should be based on  ___ not ____.

 A niche can be defined as 

A population is defined as 

The epithelium best adapted for a body surface subject to abrasion is

The advantage of excreting wastes as urea rather than as ammonia is that

Natural selection should favor the highest proportion of juxtamedullary nephrons in which of the following species?