Which of the following present challenges that make gas exchange more difficult for fish than for terrestrial animals? Select al
l that apply. A. Water is denser and more viscous than air.
B. Water contains much less O2 than air per unit volume.
C. Gills have less surface area than lungs.
D. Unidirectional flow of water is less efficient than tidal ventilation.
E. Diffusion occurs more slowly in water than in 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.
Crossing over is termed as a process by which genetic materials are exchanged by non-sister chromatids during meiosis. Crossing over results in the new combination of information in genetic for, the cell for a specific trait. It ensures that organisms are identical from one generation to another.
I think its because over the years since more individuals with high fur levels survived more harsh environment , animals have evolve high fur-level trait became more common in Population A over time, and the low fur-level trait became less common. The high fur-level trait was an more adaptive trait.