They are useful because of the way they process and digest food. They apply their enzymes externally and then absorb smaller mollecules. This process releases things like CO2 or creates alcohols, and this has historically been used in making drinks like beer or foods like bread and cheese.
Answer:
B) Nitrogen-fixing bacteria and lightning
Explanation:
Nitrogen cycle is the natural process in which atmospheric nitrogen is converted into nitrite and nitrate with the help of bacteria.
Nitrogen cycle is directly dependent on nitrogen-fixing bacteria and lightning.
As bacteria are responsible for most of the chemical conversion in the nitrogen cycle such as nitrogen fixation (first step) is done by soil bacteria (Cyanobacteria) that form ammonia, which is toxic to plants; nitrification in which ammonia is converted into nitrites and nitrates with the help of Nitrobacter and denitrification bacteria involve Pseudomonas, and Achromobacter which convert nitrite and nitrate into nitrogen.
The lightning breaks nitrogen molecules and allow it to combine with oxygen in atmosphere which further dissolve in rain and form nitrates.
Hence, the nitrogen cycle is most directly dependent upon nitrogen-fixing bacteria and lightning and the correct option is B.
━━━━━━━☆☆━━━━━━━
▹ Answer
<em>B. water cycle</em>
▹ Step-by-Step Explanation
Water is something that is dependent on amongst living things. Without the water cycle, there wouldn't be a source of water and living things wouldn't be able to survive.
Hope this helps!
CloutAnswers ❁
━━━━━━━☆☆━━━━━━━
<span>cellular respiration
Hope it helps</span>
