What nitrogen cycle process is occurring in the root nodules in the illustration?

a.) ammonification
b.) denitrification
c.) fixation
d.) nitrification

Which list is in order from simplest to most complex? a bacteria - virus - plant - protist b protist - bacteria - virus - plant c virus - bacteria - plant - protist d virus - bacteria - protist - plant

Veins have a much lower blood pressure than arteries. which of these prevents backflow of blood in veins? a. pressure applied by the heart b. one–way valves in veins c. thin muscular walls of veins

What are the pros and cons of quadrat sampling?