Explanation:
The influence from radioactivity is inversely proportional to the number of chromosomes , since , humans have more DNA , chromosomes than the insects , and therefore , due to less chromosomes in insects , they are more resistant towards radioactivity .
As the target of the radiation is the DNA .
Hence , It is clear that insect due to lesser DNA are less prone to Radiations .
Answer:
The answer is A. Invented SCUBA
Explanation:
- Emile Gagnan and Jacques Cousteau were engineers who invented the first SCUBA device, the Aqua-Lung.
- Gagnan's most important contribution to this discovery was his theory that a valve commonly used in gas generator engines would be useful in regulating air supply under water in varying pressures.
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.
What's up? the answer is B, electron
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