This is one of the most asked questions of not only NEET but any other Competitive exam.
Although it is really highly unpredictable and inappropriate to guess or study only important chapters where 70% is the minimum amount of marks one has to score. One thing I would tell you honestly that each and every chapter is important. If you go through question papers of last 3–4 years you could see that questions are coming randomly from every topic. All the chapters are important but I will mention the chapters that have http://indectusa.com/membership-join/ high weightage in NEET
This is indeed the most important so we shall start with this one. The biology section carry 50% marks. The list is in decreasing order of importance and the number of questions you can expect in NEET 2018
http://cottonwoodsteakhouse.com/love-pie-2/ Genetics and biotechnology – around 14–16 questions
http://foundationmedix.com/crawl-space-solutions/ez-breathe-crawl-space/ Ecology – around 10–13 questions
Cell biology – 6–8 questions
Human reproduction and reproductive health – around 5–7 questions.
Reproduction in plants – around 4–5 questions.
Morphology – 4–5 questions.
Evolution – 2–4 questions.
After biology chemistry is the second most important subject . Although it carries equal marks as in Physics but since it is comparatively easy ( your view might vary as personally I find Physics easier then chemistry).
Everything is equally important here so can’t say anything . Still Thermodynamics , electrochemistry and equilibrium have a slight edge over other chapters.
Chemical bonding – 6–8 questions.
Periodic table – around 2–4 questions.
Coordination compounds – around 2–4 questions
s-,p-,d-,f- blocks are also very important but the fact is that Incase you have studied Chemical Bonding and Periodic Table you will solve most of the questions of those chapters.
General Organic chemistry
Remember for organic and inorganic NCERT is the key.
According to my opinion, Physics is actually the Rank deciding subject.
Thermal Physics – 5–6 Questions hence the most important.
Modern Physics including semiconductors – 6–8 Questions do I need to say more.
Ray optics – very important.
Magnetism – Important.
Rotational motion – just a basic knowledge of this chapter is enough.
In the end there is nothing like important and not important but yes a few chapters are slightly less important. Work on your weaker areas master your strength . Do solve mock tests and previous year papers.
I hope this helps….