Class 12 Biology Ch 6 Evolution Formula Sheet PDF

Q: What is the Hardy-Weinberg formula in Class 12 Biology Chapter 6 Evolution?

The Hardy-Weinberg formula expands the binomial (p + q)2 into p2 + 2pq + q2 = 1 , where p is the dominant allele frequency, q is the recessive allele frequency, p2 is the homozygous dominant genotype frequency, 2pq is the heterozygous (carrier) frequency, and q2 is the homozygous recessive frequency. It holds in a stable, non-evolving population.

Q: How many formulas are there in Evolution Class 12 Biology?

Class 12 Biology Chapter 6 Evolution contains 17 key formulas as listed in this sheet. These cover Hardy-Weinberg equilibrium (allele and genotype frequencies), population genetics (mutation rate, migration rate, genetic drift variance, selection coefficient, relative fitness, fixation index), and radiometric dating (radioactive decay law, half-life relation, age from decay ratio). Hardy-Weinberg formulas are the most tested in NEET.

Q: What are the five conditions of Hardy-Weinberg equilibrium for NEET?

The five conditions are: a large population (no genetic drift), no mutation, no migration (no gene flow), random mating (no assortative or inbreeding effects), and no natural selection. If any one of these is violated, the genotype frequencies drift away from p2 : 2pq : q2 , which is the textbook definition of evolution at the population level.

Q: How do you solve Hardy-Weinberg numericals in NEET Class 12 Biology?

Read the prompt for the affected fraction and set it equal to q2 . Take the square root for q . Compute p = 1 - q . Plug into 2pq for the carrier frequency or p2 for the homozygous dominant frequency. This four-step workflow handles roughly three out of four NEET Hardy-Weinberg questions.

Q: What is the half-life of Carbon-14 used in fossil dating?

Carbon-14 has a half-life of 5730 years and is used to date organic fossils up to about 50,000 years old. For older fossils, NEET expects you to switch to Potassium-40 (half-life 1.25 billion years) or Uranium-238 (half-life 4.5 billion years). The decay law N = N0 e- t gives the remaining atoms after time t .

Q: What is the formula for genetic drift in Class 12 Biology?

Genetic drift variance per generation is 2 = pq / (2N) , where p and q are the current allele frequencies and N is the effective population size. As N decreases, drift increases, which is why small populations evolve faster by chance. The founder effect and the bottleneck effect are two famous Class 12 examples of drift in action.

Q: What is the selection coefficient and how is it used in Evolution?

The selection coefficient s = 1 - W , where W is the relative fitness of a genotype (best genotype takes W = 1 ). A larger s means stronger selection against that genotype. Industrial melanism in Biston betularia and sickle-cell heterozygote advantage in malaria-endemic regions are the standard CBSE and NEET examples.

Q: Is the Evolution formula sheet enough for NEET 2027 Biology?

The formula sheet covers every numerical the chapter can ask, but it does not replace the conceptual Notes for theory MCQs on Darwin, Lamarck, fossil chronology, and human evolution. Pair this Collegedunia formula sheet with the chapter Notes and the NCERT Exemplar Solutions for full NEET 2027 readiness.

NEET 2025 carried 4 questions directly from population-genetics formulas, almost all from Hardy-Weinberg. Class 12 Biology Chapter 6 Evolution packs 17 numerical formulas across allele frequency, gene flow, drift, selection, and radiometric dating into one 9-page sheet for 2026-27 NEET prep.

CBSE Weightage: 5 to 7 marks
NEET Weightage: 4 to 6 questions per paper (around 6% of Biology)
CUET Weightage: High overlap with NEET-pattern MCQs on Hardy-Weinberg and dating

Evolution Formula Sheet - Class 12 Biology

Evolution Chapter 6 Video Lecture for Class 12 Biology

Source: Magnet Brains on YouTube

All Formulas of Evolution at a Glance for NEET and CBSE Class 12

Every formula indexed against its NCERT sub-topic and exam use.

Concept	Formula	Section	Typical use
Allele frequency sum	p + q = 1	6.7	NEET MCQ on dominant frequency
Hardy-Weinberg expansion	p² + 2pq + q² = 1	6.7	Genotype from allele frequency
Homozygous recessive	q² = aa fraction	6.7	Carrier estimation
Heterozygote carrier	2pq	6.7	Sickle-cell, PKU MCQ
Allele from genotype counts	p = 2N_AA + N_Aa2N	6.7	Reverse calculation
Mutation rate	μ = new mutantstotal alleles	6.7	HWE disturbance MCQ
Migration rate	m = migrantstotal alleles	6.7	Founder-effect numericals
Allele change via migration	Δ p = m (p_m - p)	6.7	One-island models
Genetic drift variance	σ² = pq2N	6.7	Small-population MCQ
Selection coefficient	s = 1 - W	6.7	Fitness MCQ
Relative fitness	W = survival of genotypesurvival of best	6.7	Industrial melanism
Fixation index	F_ST = H_T - H_SH_T	6.7	Population differentiation
Radioactive decay law	N = N₀ e^{-λ t}	6.4	Radiometric dating MCQ
Half-life relation	t_1/2 = 0.693/λ	6.4	Carbon-14 numerical
Age from decay ratio	t = (t_1/2/ln 2)ln(N₀/N)	6.4	Fossil-age determination
Cambrian anchor	T ≈ 541 Ma	6.4	Era-matching MCQ
Origin-of-life timeline	≈ 3.5-4.0 Ga	6.2	Chronology assertion-reason

Concept: p² + 2pq + q² = 1 is the single most-tested formula. Set affected fraction = q² , take √ , find p = 1 - q , read 2pq for carriers. Three of four NEET Hardy-Weinberg numericals fit this template.

Hardy-Weinberg principle formula breakdown p squared plus 2pq plus q squared equals 1 for NEET Class 12 Biology

How will Collegedunia's Evolution Formula Sheet Help You with NEET 2027?

Engineered for last-mile NEET and CBSE revision. Every formula sits one tap away with units, exam tag, and a worked pattern.

NEET-First Design: Every formula carries the NEET-question pattern it appears in.
2026-27 NCERT Alignment: Every box mirrors the current syllabus.
Decay-and-Dating Cards: C-14, K-40, and U-238 half-lives in one card row.
Hardy-Weinberg Templates: Three worked patterns cover 80% of NEET variants.

When to Use Which Evolution Formula in NEET Numericals

Read the prompt, match a row, plug numbers.

"Frequency of recessive individuals" / % affected: use q² , then q = √q² , then p = 1 - q .
"Carrier frequency" / "heterozygous frequency": use 2pq .
"Small population" / "founder effect": use σ² = pq/(2N) .
"Fitness" / "selection against a genotype": use s = 1 - W .
"Subdivided population" / two-population differentiation: use F_ST .
"Age of a fossil" / Carbon-14: use t = (t_1/2/ln 2) ln(N₀/N) with t_1/2 = 5730 yr.
"Migration" / gene flow: use Δ p = m(p_m - p) .

Quick Tip: In NEET, the moment you see "1 in N people are affected", immediately write q² = 1/N . This single substitution unlocks every Hardy-Weinberg numerical in under 60 seconds.

Quick-Fact Cards for Evolution NEET Revision

C-14 half-life
5730 yr (fossils < 50,000 yr)

K-40 half-life
1.25 Ga (hominid dating)

U-238 half-life
4.5 Ga (Earth-age anchor)

Age of Earth
4.5 Ga (Hadean to present)

Origin of life
3.8-4.0 Ga (prokaryotes)

Homo sapiens
~0.2 Ma

Symbol Glossary for Evolution Class 12 Formulas

Every variable in the master formula table decodes here.

Symbol	Meaning	Range
p, q	Dominant, recessive allele frequencies	0-1, p + q = 1
p², 2pq, q²	AA, Aa, aa genotype frequencies	0-1
N	Population size OR remaining atoms	context-dependent
N₀	Initial radioactive atoms (t = 0)	-
λ	Decay constant	0.693 / t_1/2
t_1/2	Half-life	5730 yr C-14; 4.5 Ga U-238
s, W	Selection coefficient, relative fitness	0-1
m	Migration rate	0-1
F_ST	Fixation index between sub-populations	0-1

Six evidences for evolution palaeontological anatomical embryological molecular biogeographical vestigial

Hardy-Weinberg Numerical Templates Worked for NEET Class 12

These three templates cover nearly every Hardy-Weinberg NEET numerical.

Template 1, disease to carrier frequency. 1 in 10,000 affected: q² = 0.0001 , q = 0.01 , p = 0.99 , 2pq = 0.0198 , so 1 in 50 is a carrier.

Template 2, allele from genotype counts. 360 AA, 480 Aa, 160 aa in 1000 people: p = (720 + 480)/2000 = 0.6 , q = 0.4 . Check q² = 0.16 matches 160/1000.

Template 3, C-14 fossil dating. Fossil retains 25% C-14, so two half-lives have passed: age = 2 × 5730 = 11,460 years.

Watch Out: Hardy-Weinberg assumes random mating. If the question mentions inbreeding, assortative mating, or population subdivision, the basic p² + 2pq + q² = 1 breaks. Switch to F_ST reasoning instead.

Evolution Topic Summary Mapped to NEET High-Yield Sub-Topics

Sub-topic	NEET Frequency	Key formula
Hardy-Weinberg principle	High	p² + 2pq + q² = 1
Genetic drift, founder effect	High	σ² = pq/(2N)
Natural selection, fitness	Medium	s = 1 - W
Origin-of-life timeline	Medium	N = N₀ e^{-λ t}
Human evolution	Low	Ma anchors

One-Shot Revision Tips for Evolution Class 12 Biology

Min 1-4: Recite p² + 2pq + q² = 1 and the five HWE conditions.
Min 5-9: Walk Template 1 with q² = 1/10000 , then 1/2500.
Min 10-13: Recite half-lives: C-14 = 5730 yr, K-40 = 1.25 Ga, U-238 = 4.5 Ga.
Min 14-17: Match five forces (mutation, migration, drift, non-random mating, selection) to μ, m, σ², F_ST, s .
Min 18-20: Walk Cambrian (541 Ma) to Homo sapiens (0.2 Ma).

Remember: The mnemonic "My Mother Generally Drives Slowly" maps to the five forces breaking Hardy-Weinberg equilibrium: Mutation, Migration, Genetic drift, non-random mating (Drives), and Selection. Any one of these alone breaks the p² + 2pq + q² = 1 balance.

Evolution Class 12 PYQ Numerical Patterns Quick Recall

Pattern	Years asked (NEET)	Formula to deploy
Disease frequency to carrier frequency	2025, 2024, 2022, 2019	q² → q → 2pq
Allele frequency from genotype counts	2023, 2021, 2018	p = (2N_AA + N_Aa)/2N
Fossil age from remaining isotope fraction	2024, 2022, 2020	t = (t_1/2/ln 2) ln(N₀/N)

Student Feedback on Chapter 6 Evolution Class 12 Biology

Student Feedback

What 10,900 students told us about the Chapter 6 Evolution Formula Sheet:

72% of students marked the Hardy-Weinberg equation derivation as the hardest sub-topic in Chapter 6.
Average student took 5.4 hours for the first read, and 2.3 hours for a focused revision pass before boards.
Of 10,900 students, only 36% attempted all 12 NCERT exercise questions. Toppers attempted every question and revisited wrong attempts within 24 hours.

Source: 2025-26 Class 12 Biology student survey. Sample of 10,900 students from CBSE-affiliated schools across 18 states.

Other Resources for Evolution Class 12 Biology

Resource	Link
Formula Sheet	Evolution Class 12 Biology Formula Sheet
NCERT Book PDF	Evolution Class 12 Biology NCERT Book PDF
NCERT Solutions	Evolution Class 12 Biology NCERT Solutions
Notes	Class 12 Biology Chapter 6 Evolution Notes
Exemplar Book PDF	Class 12 Biology Chapter 6 Evolution Exemplar Book PDF
Exemplar Solutions	Class 12 Biology Chapter 6 Evolution Exemplar Solutions
Handwritten Notes	Class 12 Biology Chapter 6 Evolution Handwritten Notes

NCERT Formula Sheet for Class 12 Biology: All Chapters

Browse the formula sheets for every Class 12 Biology chapter in the 2026-27 NCERT.

Chapter	Resource
Chapter 1	Sexual Reproduction Formula Sheet
Chapter 2	Human Reproduction Formula Sheet
Chapter 3	Reproductive Health Formula Sheet
Chapter 4	Inheritance and Variation Formula Sheet
Chapter 5	Molecular Basis of Inheritance
Chapter 6	Evolution Formula Sheet
Chapter 7	Human Health and Disease
Chapter 8	Microbes in Human Welfare
Chapter 9	Biotechnology Principles
Chapter 10	Biotechnology Applications
Chapter 11	Organisms and Populations
Chapter 12	Ecosystem
Chapter 13	Biodiversity and Conservation

Evolution Class 12 Biology Formula Sheet FAQs

What is the Hardy-Weinberg formula in Class 12 Biology Chapter 6 Evolution?

The Hardy-Weinberg formula expands the binomial (p + q)² into p² + 2pq + q² = 1 , where p is the dominant allele frequency, q is the recessive allele frequency, p² is the homozygous dominant genotype frequency, 2pq is the heterozygous (carrier) frequency, and q² is the homozygous recessive frequency. It holds in a stable, non-evolving population.

How many formulas are there in Evolution Class 12 Biology?

Class 12 Biology Chapter 6 Evolution contains 17 key formulas as listed in this sheet. These cover Hardy-Weinberg equilibrium (allele and genotype frequencies), population genetics (mutation rate, migration rate, genetic drift variance, selection coefficient, relative fitness, fixation index), and radiometric dating (radioactive decay law, half-life relation, age from decay ratio). Hardy-Weinberg formulas are the most tested in NEET.

What are the five conditions of Hardy-Weinberg equilibrium for NEET?

The five conditions are: a large population (no genetic drift), no mutation, no migration (no gene flow), random mating (no assortative or inbreeding effects), and no natural selection. If any one of these is violated, the genotype frequencies drift away from p² : 2pq : q² , which is the textbook definition of evolution at the population level.

How do you solve Hardy-Weinberg numericals in NEET Class 12 Biology?

Read the prompt for the affected fraction and set it equal to q² . Take the square root for q . Compute p = 1 - q . Plug into 2pq for the carrier frequency or p² for the homozygous dominant frequency. This four-step workflow handles roughly three out of four NEET Hardy-Weinberg questions.

What is the half-life of Carbon-14 used in fossil dating?

Carbon-14 has a half-life of 5730 years and is used to date organic fossils up to about 50,000 years old. For older fossils, NEET expects you to switch to Potassium-40 (half-life 1.25 billion years) or Uranium-238 (half-life 4.5 billion years). The decay law N = N₀ e^{-λ t} gives the remaining atoms after time t .

What is the formula for genetic drift in Class 12 Biology?

Genetic drift variance per generation is σ² = pq / (2N) , where p and q are the current allele frequencies and N is the effective population size. As N decreases, drift increases, which is why small populations evolve faster by chance. The founder effect and the bottleneck effect are two famous Class 12 examples of drift in action.

What is the selection coefficient and how is it used in Evolution?

The selection coefficient s = 1 - W , where W is the relative fitness of a genotype (best genotype takes W = 1 ). A larger s means stronger selection against that genotype. Industrial melanism in Biston betularia and sickle-cell heterozygote advantage in malaria-endemic regions are the standard CBSE and NEET examples.

Is the Evolution formula sheet enough for NEET 2027 Biology?