Fishes in water bodies that are frozen on the top often gather in groups near the bottom This is bec...........

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Fishes in water bodies, that are frozen on the top, often gather in groups near the bottom. This is because

1. Warm water sinks at the bottom of the lake that is very cold on the top.

2. Ice on the top of the water body insulates the water body making the bottoms liveable.

Which of the above is/are correct?

1 only

2 only

Both 1 and 2

None

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Explanation:

Statement 1: During summer, the deeper you dive, the colder the water gets. During winter the opposite happens. The frigid water actually gets relatively warmer the deeper you descend in a lake. The reason has to do with how water molecules arrange. As water cools, the molecules sink and pack tighter and tighter together (increasing density) until the temperature drops to nearly 4 degrees Celsius. At that point, the water molecules are heavier than the water at the surface (that is freezing), causing a topsy-turvy effect where warmer water is at the bottom.
Statement 2: The layer of ice that forms on top of a lake, pond, river, or stream provides some insulation that helps the waterbody retain its heat. This is similar to the insulation offered by Igloos made in the Northern pole.

In this resting state, fishes' hearts slow down, their needs for food and oxygen decrease, and they move about very little. As cold-blooded creatures, their metabolism dips when temperatures take a dive.