They both contain nucleus.
Answer:
the dissolved oxygen of the water decreases.
the fish need the oxygen for respiration, breathing through their gills.
Explanation:
The salinity decreasing doesn't affect the pickerel, because it's a freshwater fish. no salt needed.
more light penetrating the water just means that more aquatic weed or grasses would grow, giving the pickerel more area to spawn their eggs.
temperature increase in the summer has no affect on the fish, since the spawning happens in late winter.
Answer:
T and B cells.
Explanation:
Adaptive immunity is the kind of immunity that you acquire after exposure to an antigen (pathogen or vaccine), it involves memory in order to facilitate a quick response if there's a reinfection with the same pathogen.<em> T cells are responsible for the cell-mediated response while the B cells are responsible for the humoral response.</em> Both of these cells are specific to the pathogen's structure, therefore they can kill it directly.
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