For neet exam is there any definite mark structure for each chapters?

No there's no definite marks structure for preparing the NEET examination based on the chapters the NEET examination is a competitive examination and any question can be asked from any topic many students ask the same question about the weighted chapters and all but I would like to tell you that all chapters are equally important nothing is less or more for the NEET examination so just study for all the topics.

hi afsha , there is no fixed mark structure, but i could tell you where the weightage was more last year.but do bear in mind that it varies from time to time

Physics : Mechanics is the most important topic. 12-13 questions were asked on it last time.

Chemistry : Organic Chemistry dominates the chemistry question paper. 14-15 questions were from topics related to it.

Biology : There was a more uniform distribution of questions in Biology. There was no single unit or topic from which more than 6 questions were asked. Hence it would be wrong to deem any one single chapter most important as all are important

Hello buddy! Mark distribution varies every year and it is not wise to rely on it. However, plant morhoplogy, taxonomy, genetics n biochemistry,  kinematics, electromagnetism, modern physics, physical chemistry are some of scoring areas.
All the best !

No there isn't any fixed mark structure.

Hey !
The mark distribution is not always fixed but is around high weightage chapters are around this pattern

For physics
Topics. Number of questions
1)Mechanics 13
2)Electrodynamics 10
3)Modern Physics 8
4)Optics 5
5)Heat and Thermodynamics 5
6)SHM & Waves 4
Chemistry
Inorganic 15
1)P-block 4
2)Chemical bonding 3
3)Periodic table 4
Organic 16( all the chapters are equally important )
1) chemistry in everyday life 2
2) aldehyde ketone
3) isomerism
Physical 14( no specific pattern , one question from each chapter mostly)
1) equilibrium
Biology
1) human physiology : 16
2) molecular bases of inheritance 6
3) plant Kingdom 6
4) reproduction in plants 5
5) ecology 5
6) genetics 5
All the best !
Pratiksha ( CR@CAREERS360)

Their is no definite structure as such. It can be vary.

With the help of past year analysis you will get to know about the important chapters which will help you to score good marks in your exam.

To get an idea about the important chapters and to know chapter- wise weightage you can refer below link

NEET Analysis 2017

Good luck!!