Most Frequently Asked Concepts in NEET Biology (2021–2025): Chapter-Wise

Chapter-Wise Weightage of NEET Biology (2021–2025)

Biology is a major part of the NEET 2026 syllabus, accounting for 50% of the total marks. Focusing on chapters that frequently appear in the exam can help increase the score. Analysing NEET Biology trends from 2021 to 2025 shows which chapters are high-weightage.

NEET Chapter-wise weightage analysis for biology is given below. This will help students prioritise topics and plan their revision more effectively.

The data is from the last five years, and the chapters on plant transport, food production improvement strategies, digestion and absorption, organism reproduction, and mineral nutrition are no longer part of the syllabus.

Frequently Asked Concepts in NEET Biology (2021–2025)

Certain NEET Biology topics appeared repeatedly from 2021–2025. Focusing on these high-frequency concepts will help students revise efficiently, study smart, and maximise their score in the NEET 2026.

Important Concepts Based Questions for NEET 2026 Biology

Understanding concept-based questions is key to scoring well in NEET Biology. These questions test how well aspirants can apply concepts, not just recall facts. By practising top 100 NEET biology questions to score 330+ marks, students can improve accuracy and build confidence for the actual exam. Some important concepts based on previous year NEET biology questions are given below:

Ques: In a cross between a male and female, both heterozygous for the sickle cell anaemia gene, what percentage of the progeny will be diseased? (NEET 2021)

Option 1) 50 %

Option 2) 75 %

Option 3) 25 %

Option 4) 100 %

Correct Answer: 25%

Chapter: Principles of Inheritance and Variation

Explanation:

Autosomal recessive inheritance is the mode of inheritance for sickle cell disease. Thus, an individual has to inherit two copies of the mutated HBB gene-one from each parent-to be affected. This will affect about 25% of the offspring when both parents are carriers (sickle cell trait). Carriers have genotype AS and are usually asymptomatic but can pass the gene to their children.

Hence, the correct answer is Option 3) 25%

Ques: Which of the following are Autoimmune disorders? (NEET 2024)

A. Myasthenia gravis

B. Rheumatoid arthritis

C. Gout

D. Muscular dystrophy

E. Systemic Lupus Erythematosus (SLE)

Choose the most appropriate answer from the options given below:

Chapter: Human Health and Disease

Option 1) A, B & D only

Option 2) A, B & E only

Option 3) B, C & E only

Option 4) C, D & E only

Correct Answer: A, B & E only

Explanation: Autoimmune disorders are conditions wherein the immune system erroneously targets the body's cells, perceiving them as foreign entities.

The correct answer is option (2) as Myasthenia gravis, Rheumatoid arthritis and Systemic Lupus Erythematosus (SLE) are autoimmune disorders.
Muscular dystrophy is a genetic disorder which progressively affects the skeletal muscles.
Gout is the inflammation of joints due to the deposition of uric acid crystals.

Hence, the correct answer is option 2) A, B & E only.

Ques: Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (NEET 2025)

Assertion (A): Both wind and water-pollinated flowers are not very colourful and do not produce nectar.

Reason (R): The flowers produce an enormous amount of pollen grains in the wind and water-pollinated flowers.

In light of the above statements, choose to correct answer from the options given below:

Chapter: Sexual Reproduction in Flowering Plants

Option 1) A is false, but R is true

Option 2) Both A and R are true, and R is the correct explanation of A

Option 3) Both A and R are true, but R is NOT the correct explanation of A

Option 4) A is true, but R is false

Correct Answer: Both A and R are true, but R is NOT the correct explanation of A

Explanation:

Assertion (A): Wind and water-pollinated flowers are generally not colourful and do not produce nectar because they do not require any pollinators such as birds or insects.
Reason (R): These flowers produce a large number of pollen grains, so the chances of pollination will increase. But the absence of nectar and colour is because no pollinators are required by these flowers.

Hence, the correct answer is option(3), both A and R are true, but R is NOT the correct explanation of A.

NEET Biology 2026 Important Concepts Preparation Strategy

Smart preparation is the key to scoring well in NEET 2026 Biology. These proven strategies will help students build strong concepts, retain information longer, and attempt exams with confidence:

Conceptual Clarity over Rote Learning

• NEET Biology tests your understanding, not memory.

• Pay attention to the logic behind each concept rather than mugging up definitions.

• Understand how and why something occurs – such as enzyme activity or genetic differences.

• Concepts free from confusion help students answer application-based questions correctly.

• Always refer to NCERT diagrams and examples, since many questions are directly framed from them.

Regular Revision Schedule

• Regular revision helps in long-term memory.

• Plan a weekly schedule to go through 3–4 chapters you've already read.

• Use flashcards, short note cards, or summary sheets to speed up revision.

• Don't wait until the exam to start revising; instead, continue to do so throughout your preparation.

Practice Previous Year Questions

• Attempting previous year's NEET Biology questions helps to understand trends and patterns.

• Determine which areas appear frequently in previous papers.

• Attempt topic-wise questions immediately after finishing each chapter.

• Attempt NEET biology mock tests to improve speed, accuracy, and time management.

• Carefully analyse mistakes and improve your weak spots.

Recommended Study Materials for NEET 2026

• Start with NCERT Biology (Class 11 & 12) – it's the base of the NEET syllabus.

• NEET Biology questions are mostly derived directly from the NCERT text.

• Use good additional books, such as MTG NEET Biology and Trueman's Biology.

• Avoid using too many books; instead, study from a few and revise them several times.