Question 1
What does the pink center of the nodules on the roots of leguminous plants indicate?
◦ scattered nodules over the entire root system
◦ active fixation of nitrogen by rhizobia
◦ inactivity of rhizobial enzymes
◦ nodules greater than 6 mm in diameter
Question 2
Which form of soil nitrogen is most abundant in soil?
◦ amino sugars
◦ amino acids
◦ nitrous oxide
◦ nitrogen dioxide