Eutrophication is the overgrowth of algae in lakes and ponds
that is usually caused by the introduction of different chemicals
into the water from fertilizer run-off. Some ways to combat this
are to increase the flow of moving water, prevent contamination
from fertilizer, and reduce pollution of our lakes and streams.
Mutation can cause instant adaptation while natural selection is the process by which adaptation occurs over a series of generations.
In prophase 1:
Chromosomes become visible, crossing-over occurs, the nucleolus disappears, the meiotic spindle forms, and the nuclear envelope disappears.
In metaphase 1:
The pairs of chromosomes (bivalents) become arranged on the metaphase plate and are attached to the now fully formed meiotic spindle. The centrioles are at opposite poles of the cell.
Since the
speed of many physiological processes in marine organisms is determined by the
temperature, the first consequence of the changes in the conditions of the
medium becomes offset the timing of seasonal events, such as the timing of
spawning fish. There have also offset migration routes and spawning areas. So,
as a result of warming in the Sea of Japan, spawning navaga shifted to an
earlier date, because of the reduction of the area of "cold spots"
in the eastern Bering Sea shelf feeding migration of pollock, halibut and crab
are lengthened, but because of the temperature rise to the east of Japan,
spawning saury expanding. These changes significantly affect the success of
reproduction, resulting in changes populations of their fishery.
