Final answer:
Scientific knowledge is established through systematic study and the scientific method, which includes making observations, formulating hypotheses, and conducting experiments. Scientific knowledge can change when new observations challenge existing ideas, and paradigm shifts can result in dramatic changes in scientific understanding.
Step-by-step explanation:
Scientific knowledge is established through systematic study and the use of the scientific method. The scientific method involves making observations, formulating hypotheses, designing experiments, and conducting repeated cycles of observation, hypothesis, and experimentation.
Scientific knowledge can change when new observations are made that challenge existing ideas. As scientists make new discoveries and gather more information, they may revise or replace existing theories and explanations to better fit the new evidence.
An example of a dramatic change in scientific understanding is called a paradigm shift. These occur when there is a radical change in scientific ideas, often resulting in a significant shift in the prevailing scientific consensus.