Of course an Extended Essay can be completed in Biology. It is best then – perhaps obligatory – to think about an experimentally based EE. Take an experimental technique and modify it, and fit it to your specific research question, so that results you obtain are original or can be analysed in an original way. This personalises your EE.
The FOREMOST piece of advice that I can give is:
KEEP YOUR RESEARCH QUESTION AND EXPECTATIONS SIMPLE AND SPECIFIC. DO NOT TRY TO OVER-COMPLICATE THINGS OR BE TOO AMBITIOUS OR GRANDIOSE.
THE IB GUIDE FOR EXTENDED ESSAYS
This is a long read! Much of it is taken up with the manner in which the assessment criteria are used in specific subject areas. The Biology-specific content begins on Page 43. I believe that it is important that IB candidates are acquainted with and have a good awareness of this IB Guide before they set out on the EE road. That will help focus ideas.
MODEL EXTENDED ESSAYS
These 3 essays are several years old but have been used by the IB as models of well researched and written EE’s. It is important to recognise what a good EE in Biology looks like, so that you have something to aim for. Although these essays would have been assessed according to different criteria, they still would be top scorers in the new rubric.
SCHOOL HANDBOOK FOR THE EXTENDED ESSAY
Most IB schools will have prepared a handbook to advise students how to go about starting and completing their Extended Essay. It will look something like this edited version of the Handbook from John F. Kennedy High School in Denver, Colorado:
Before you set out to actually working your EE, you must be absolutely clear about what you want to do and whether it is feasible and viable. Thus an EE Proposal, written formally, is fundamental. Your IB Coordinator will probably ask for this anyway, and your Supervisor should not agree to work with you until when you have provided a detailed proposal.
Here are Proposal Guidelines and a Template you can use:
Advice on writing a research paper: How to write a research paper