Which of the following organisms is included in the Kingdom Monera? MCQ with Answer and Explanation

Explanation:
Biological nitrogen fixation, performed by bacteria (Rhizobium, Azotobacter) and cyanobacteria, reduces N₂ to NH₃. Nitrification oxidizes ammonia to nitrates, denitrification returns N₂, ammonification releases ammonia from organic matter.

Explanation:
Alveoli are tiny air sacs surrounded by capillaries where gas exchange (O₂ and CO₂) occurs. Nephrons are kidney units, neurons nerve cells, villi intestinal projections. The lungs contain millions of alveoli to maximize surface area.

Explanation:
Apical meristems at root and shoot tips contribute to primary growth (increase in length). Intercalary meristems, located at nodes and leaf bases, also aid in elongation, especially in grasses. Lateral meristems (vascular cambium, cork cambium) cause secondary growth (increase in girth). So both apical and intercalary meristems are responsible for length increase.