The branch of biology dealing with interactions along organisms and between organisms and their environment is called Ecology, I believe.
The order should be..
Ask a question
State a hypothesis
Test a hypothesis
Collect data
Analyze data
Write up conclusion based on data
Share your findings by presenting or publishing
Express ideas to make this experiment better in the future
I hope this helps! Please let me know if any are out of order so I can correct it in the future.
Programmed Theories - it suggests that our body is designed to age and that there is a timeline that our bodies follow, and switch in our genes that switches off over time.
Error Theories - we age because of environmental hazards that our bodies accumulate over time.