Evolution — Class 12 CBSE Biology revision notes
A 6-page visual revision sheet for Evolution, written for Class 12 CBSE Biology. Formulas, diagrams and the traps that cost marks, laid out to be read the night before rather than the term before. Free, and it opens inside CapCompass.
Page 1 as PDF
Evolution in one look
variation already exists; selection just decides which of it sticks around
Origin of life
- spontaneous generation: life springing suddenly from non-living matter, a disproved idea
- controlled experiments showed life arises only from pre-existing life, never spontaneously
- Oparin and Haldane: first life arose gradually via chemical reactions among simple inorganic molecules
- these reactions proceeded under the physical and chemical conditions of early Earth
Miller-Urey experiment vs the early atmosphere it modelled
| Feature | Early atmosphere (proposed) | Miller-Urey flask |
|---|---|---|
| Gases used | methane, ammonia, hydrogen, water vapour | methane, ammonia, hydrogen, water vapour |
| Energy source | lightning, UV radiation, heat (proposed) | an electric discharge (spark) |
| Result | simple organic molecules (hypothesised) | amino acids formed and detected |
Page 1 of 6. The full sheet, all 6 pages, opens free in the app.
What this Evolution sheet covers
- Origin of life
- Miller-Urey experiment vs the early atmosphere it modelled
- From a bare planet to us
- Evidence for evolution
- Fossils in rock strata
- Connecting links
- Embryology
- Vestigial organs
- Molecular evidence
- Homologous vs Analogous organs
- Homologous organs
- Analogous organs
- Adaptive radiation
- Microevolution vs Macroevolution
- Microevolution
- Macroevolution
- Lamarckism vs Darwinism
- Lamarckism
- Darwinism
- Darwin's postulates
- A mnemonic for the four postulates
- Types of natural selection
- The Hardy-Weinberg principle
- Working out allele frequencies from a recessive trait
- What equilibrium looks like
- Gene flow, genetic drift and the founder effect
- Where the variation comes from
- Human evolution
- Traps that cost marks
- Tricks that save time
How CapCompass uses this sheet
These notes are not a standalone PDF. CapCompass plans Biology chapter by chapter against your real exam dates and free hours, and when the plan reaches Evolution the sheet opens inside the study block itself — at the page covering the sub-topic that block is on, with the timer still running. Revision arrives at the moment the plan says revise, instead of having to be gone looking for.
More Biology Class 12 revision notes
- Biodiversity and Conservation
- Biotechnology and its Applications
- Biotechnology: Principles and Processes
- Ecosystem
- Human Health and Disease
- Human Reproduction
- Microbes in Human Welfare
- Molecular Basis of Inheritance
- Organisms and Populations
- Principles of Inheritance and Variation
- Reproductive Health
- Sexual Reproduction in Flowering Plants