The answer is #4. The first and second one involve acid, which is chemical weathering. The third one involves oxidation, which is a chemical process. The only mechanical process is option four.
B. An ecosystem in which plant roots are submerged during parts of the years
Answer:
Bacteria that metabolize NO2- to give rise to NH4+ belongs to the family of denitrifying bacteria and nitrate ammonification bacteria such as pseudomonas.
Explanation:
Denitrifying bacteria uses NO2- as electron aceeptor thus converting the nitrite ion (NO2-) to ammonium ion(NH4+).
a) The above reaction is a reduction reaction because NO2- or nitrite ion accept electron to generated its reduced form known as ammonium(NH4+).
b) NO2- acting as electron acceptor in this reaction.
<span>Cytotoxic t-cell subpopulations are specialized to combat intracellular pathogens, whereas helper t-cell subpopulations are specialized to combat extracellular pathogens.
</span>Cytotoxic t-cell are CD8+ cells. Cytotoxic t-cell uses granzymes to <span>kill </span><span>intracellular bacteria, that lives in the cytosol such as viruses. They identify the pathogen forgein peptids that are bounded to MHC-I on the cell surface.
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cd4+ T helper (Th) cells include Th1, Th2, and Th17 cells. They contribute to aliergic reactions and fighting extracellular parasites.
