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: B. littoral zone
Explanation: Their primary prey, insects, live or fly near the shallow and outside edges of ponds and lakes. There is also less predator fish at the edges of lakes and ponds.
The correct answer is D: I and II only.
Viruses have protein capsids, which protect their genetic material. This capsid sometimes is covered by viral envelopes which have glycoproteins on their surface. Glycoproteins help in the process of binding to the host cell and infecting it. In this example, virus III has the structure of a bacteriophage and it does not seem to have glycoproteins. Bacteriophages use their tail fibers to attach to the bacterial host and inject their genetic material. On the contrary, viruses I and II have glycoproteins sticking out of their envelopes.
Answer: C) Centromeres
Explanation: Centromeres are involved in crossing over, none of the other ones are.
