We cite, or refer to, our sources in research assignments for (basically) 4 reasons:
To give credit to (or not take the blame for!) the "author" of the idea or quote
To support and highlight our own idea/argument
To show evidence of all the research we have done
To become part of the academic or scholarly "conversation" about our topic
Watch this 90-second video about why we cite to get a clear picture of why it's so important to use citations:
What if rappers had to cite all their pop-culture references? How many of these would you recognize without the citations?