<span>The question says,'...........convert ammonium into nitrates whilw .........converts nitrates into nitrogen gas. The correct option is A. Nitrification is a two stage process by which ammonia or ammonium is biologically oxidised to nitrate while dentrification is the biological oxidation of nitrate to nitrogen gas by dentrifying bacteria.</span>
Gametes are an organism's reproductive cells
Answer: e. generation time
Explanation:
The generation time is the time that is required by the bacterial cell or cell of the any other organism required to be doubled in number during a specified or constant period of time. The generation time can vary in different organisms.
For example, the E.coli cell divides in every 20 minutes, hence, the generation time of the E.coli is 20 minutes and for the Staphylococcus aureus it is seen as 30 minutes.
Answer:
d. Citric acid cycle
Explanation:
The only process in the list that requires the presence of O2 in order to occur is the Citric acid cycle or Krebs cycle. This cycle is part of the aerobic cellular respiration and it occurs only when O2 is available. If there is no oxygen, an alternative process that could happen is fermentation, but this is only carried by some microorganisms and some cells such as muscle cells.
In fact, oxygen is not needed by citric acid cycle but it is by the next step: the electron transport chain. In this chain, oxygen is the final acceptor of electrons, and without oxygen, the Krebs cycle doesn't occur because the final electron transport chain can't be done.
Answer:
Asteroids, meteors, meteorites, gases (such as helium).
Hope this helps.