When a lake freezes, how does the density of water prevent all of the living organisms in the lake from freezing as well?

Because ice is less dense than liquid water (because the water molecules for a new, large structure as they cool down), lakes freeze from the top down even though the coldest areas are at the bottom--cold water rises when it begins to freeze and accumulates at the top in a sheet of ice.

Explanation:

The ice provides some insulation the water below, so that there is typically a significant portion of liquid water under the ice sheet, unless it is extraordinarily cold for a long time. If lakes froze from the bottom up, they would be more likely to freeze completely.

it gets less dense

Explanation:

That is why ice cubes float in a glass of water. It also takes a lot of energy removal to freeze water, and the air is usually much colder than the earth at the bottom of the lake.

step 1 ammonium can be absorbed by plants, but some is converted into nitrates which are better for plants to absorb. this is called nitrification. 2. step 2 the deer eats the plants and uses the nitrogen-containing proteins for cell growth. 3. step 3 bacteria in the soil conduct nitrogen fixation to convert nitrogen gas from the atmosphere into ammonium. 4. step 4 some of the nitrates are absorbed back into plants, but denitrification breaks down the nitrates into nitrogen gas released back into the atmosphere. 5. step 5 nitrogen is found in the urine, which gets broken down into ammonium through the process of ammonification. 6. step 6 plants absorb the ammonium and begin assimilation, the process to add the nitrogen to protein.

b ti isnfornopgnoernfrof