Iterative model is significantly different than other models of project management. Do you need to collect requirements if your project follows this model? Check out the answer in this video
RELATED LINKS
PROJECT MANAGEMENT LIFE CYCLES (WATERFALL, AGILE, ITERATIVE)
https://www.youtube.com/watch?v=mWCzrGlcwLg&list=PLLRADeJk4TCJeJlu-3Bw3eLzIbYWDAyXm
SCOPE MANAGEMENT FAQs
https://www.youtube.com/watch?v=Zup8J-IGo_8&list=PLLRADeJk4TCLL5biuiHD3LJN8jpN2jinz
SHOP FOR PMP AT AMAZON INDIA
http://amzn.to/2xjhXlS