To bring oxygen in the body because it is a respiratory organ fish
Answer:
They contain different genetic material.
Explanation:
DNA viruses contain DNA for genetic material while RNA viruses contain RNA. When RNA viruses enter a host cell, they must convert their RNA into DNA. DNA viruses change the biochemical functions in the nucleus for DNA replication and creates RNA that controls the proteins needed by the DNA virus (capsid).
Answer:
Natural selection.
Explanation:
Imagine in the beginning there was a single species of bird. Naturally, this bird had to expand to the rest of the world, and was distanced as the continents drifted off. But this bird had to cope with various climates and environments. So the bird would gradually mutate over time. The bird in the jungles of central america would develop different colors and a shaped beak, and would better help it survive. This led to being the new normal for birds of this area. It would evolve to cover all the surviving birds in the region, until it is so drastically changed then it is a new species. There are so many different environments, each with its own challenges to overcome, so so many different bird evolve to survive them.
I think the correct answer from the choices listed above is option A. Cells divide in order to maintain a surface area large enough to support their cytoplasm. When they divide, their volume decreases which enables them to obtain enough nutrient and expel wastes.
