Question

If the water temperature in a lake drops from 25°C to 10°C, what effect is it likely to have on aquatic animals that have a high demand for dissolved oxygen?

They will find it easier to meet their needs for dissolved oxygen.
They will find it harder to meet their needs for dissolved oxygen.
They will leave the lake and find another with warmer water.
They will adapt to the change in temperature and use more dissolved oxygen.

Answer 1

For dissolved gases, as the temperature decreases, the solubility increases. Since the temperature is decreasing, there will be more oxygen available so the aquatic animals will find it easier to meet their needs for dissolved oxygen.

Answer 2

They will find it easier to meet their needs for dissolved oxygen.

Step-by-step explanation:

Oxygen solubility in water is increased with reduction in the temperature of water. Increasing temperature imparts kinetic energy to oxygen atoms which escape the water. Lowering down the temperature reduces their kinetic energy and the increased solubility of oxygen in water would make it easily available for the organisms of water with high oxygen demand.