Question

In higher latitudes where lakes freeze over in winter, how do cool fall temperatures help fish make it through the winter?

1.) The cooling water slows fish metabolisms down and allows them to go into hibernation in winter.
2.) Water from the bottom of the lake raises and provides oxygen to the cooler waters on the surface.
3.) Cool water at the surface traps nutrients deep in the lake to provide food during the winter.
4.) The water in contact with the air sinks and mixes with the less oxygenated water in the deeper levels.

Answer 1

The cool fall temperatures help fish make it through the winter by causing fall turnover, where oxygen-rich water at the surface of the lake moves to the bottom, providing oxygen to the cooler waters on the surface.

Step-by-step explanation:

As air temperatures drop in the fall, the temperature of the lake water cools to 4 °C. This causes fall turnover as the heavy cold water sinks and displaces the water at the bottom. The oxygen-rich water at the surface of the lake then moves to the bottom, providing oxygen to the cooler waters on the surface. During the winter, the oxygen at the bottom of the lake is used by fish and other organisms requiring oxygen.

Answer 2

Correct answer: 3.) Cool water at the surface traps nutrients deep in the lake to provide food during the winter. D

During the winter, only the top layer of river freezes, under the upper surface water is found in its liquid form and it does not freeze.

Oxygen is trapped under the layer of ice, as a result of this fish are able to live comfortably inside the frozen lakes and ponds.

Due to this the icy waters of the Arctic and Antarctic Oceans support a great amount of marine life