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:
Option (2).
Explanation:
Zygote is formed by the fusion of the male and female gamete during the process of sexual reproduction. The zygote undergoes further development inside the female womb.
The embryonic period starts from the third week after the conception. The important organs and structure development occur during the embryonic period. The formation of three germ layers occur in this period.
Thus, the correct answer is option (2)
Answer:
it has thermal energy but at a less amount.
Explanation:
like know how heat transfers to hight tempter to low. some thing like that
Hurricane Katrina was a density-dependent factor because this disaster affected everyone in the area. It did not selectively have an effect like
