Answer:
B. Geographic Isolation
Explanation:
Speciation is a biological process that allows the generation of new species through existing species. Through conditions imposed by the environment in which this species lives.
Speciation is usually caused by geographic isolation.
Geographic isolation occurs when a population of the same species is separated by some type of natural barrier, such as rivers or mountains. This causes the population to be divided in two and begin to face different environments and different environmental conditions. This causes each part of the population to adapt in different ways, leaving them so different from one another that it is no longer possible to say that the two populations belong to the same species.
Answer: germ theory
Explanation: Germ theory of disease is a theory in biology. It says that small organisms (called germs), also known as microbes, cause diseases. Most, but not all diseases are infectious diseases. The germ theory states that small organisms cause a reaction in the body of those who are infected. The body's reaction to infection is called a disease.
Reference: Wikipedia
the center of the solar system is the sun
Answer:
Since the origin of humans on this planet, they have been trying their best to make their lives easier on this planet. In doing so, human activities have some how heavily damaged the Earth. Many day to day activities of humans are dangerous for the Earth.
Some of the consequences of human activities on the Earth's fresh water are :
Extinction of many aquatic species:
The water consumed by humans comes from the fresh water oceans. As the population of humans is increasing enormously, the water from the oceans is being consumed at dangerous levels. This has caused many species of aquatic animals to become extinct or to be at a verge of extinction as they do not have a habitat to survive or reproduce.
Pollution:
Many heavy industries, house sewage, farmers dispose waste into the fresh water. Hence, killing aquatic animals and polluting the fresh water ecosystems.