HIV directly attacks CD4 helper lymphocytes directly. (D)
The present is the key to the pats because what you have done in the past is what has now brought you to where you are now, it was the stepping stones
Answer:
Ammonification
Explanation:
The ammonification is part of the nitrogen cycle. This process occurs when the plants and animals die. The dead plants and animals start to decompose because of the organisms like the fungi and bacteria that manage to decompose them. As they are decomposed, the nitrogen is converted into ammonium by the decomposers. The ammonium is returned into the soil, thus becoming available for the living organisms that can extract it from it, and in that manner continuing the nitrogen cycle.
The molecular clock tracks down nucleotide sequences for DNA or amino acids that contain sequences of proteins. Scientists use this to deduce the time in history where life forms possibly have diverged. This technique is also known as a gene clock or an evolutionary clock.
