The answer is d. carry on metabolism.
Metabolism includes all chemical reactions involved in maintaining order within cells and organs. The purpose of metabolism is a conversion of food or fuel to building blocks for macromolecules and to energy for cellular processes. It is involved in the elimination of waste, too. Regulation of metabolism is important for normal functioning of cells and organs.
The most common form of entry of the phosphorus is by human use of the fertilizers which is released into the groundwater.
Most of the fertilizers being used in agriculture contains nitrogen and phosphorus which is carried to the aquatic ecosystem through surface runoff. When the tropical rainforest are cut down by humans and fertilizers are being used in large amounts the nutrients stored in plants or rocks are washed by the heavy rains and they reach groundwater or other water bodies. Therefore, the humans alter the natural phosphorus cycle majorly in several mentioned ways.
Answer:
A. Water is denser and more viscous than air.
B. Water contains much less O2 than air per unit volume.
E. Diffusion occurs more slowly in water than in air.
Explanation:
The gas exchange for aquatic animals is more difficult than for terrestrial animal because of several reasons like water is denser and vicious than air so the diffusion of oxygen in air is much faster than the diffusion of oxygen in the water.
The concentration of oxygen in the air is much higher than the concentration in the water. In air the concentration of oxygen in 21% but in water, it is a tiny fraction of 1 percent oxygen. The oxygen holding capacity of warm water becomes less in cold water. So the right answer is A, B, and E.
