Mendel:

  • Gregor Mendel is the father of modern genetics.

  • Laws of Inheritance: Law of Segregation and Law of Independent Assortment.

  • Traits are determined by discrete units called genes.

  • Genes are inherited in a predictable manner.

Photosynthesis:

  • Converts sunlight into chemical energy (glucose and oxygen).

  • Occurs in chloroplasts with chlorophyll pigments.

  • Essential for plant energy and oxygen production.

  • Basis of food chains and oxygen levels on Earth.

Evolution - Origin of Universe:

  • Big Bang theory: Universe started as a singularity.

  • Rapid expansion created space, time, matter.

  • Led to galaxy, star, and planet formation.

  • Explains universe’s origin, structure, and expansion.

Origin of Earth:

  • Earth formed 4.5 billion years ago.

  • Developed layers: crust, mantle, core.

  • Shaped by geological processes: tectonics, volcanism, erosion.

  • Crucial for understanding life’s development.

Theory of Biogenesis:

  • Living organisms arise from pre-existing life.

  • Rejects spontaneous generation (life from non-life).

  • Supported by experiments by Louis Pasteur.

Origin of Cellular Forms:

  • Simple, single-celled organisms likely preceded complex life.

  • RNA world hypothesis explores early life’s origin.

  • Hydrothermal vent theories also considered.

Theories of Evolution:

  • Darwin’s Theory of Natural Selection and Wallace’s theory.

  • Organisms with advantageous traits survive and reproduce.

  • Gradual change and adaptation over generations.

  • Explains diversity and interconnectedness of life.

Criticism of Lamarck’s Theory:

  • Lamarck proposed acquired traits inheritance.

  • Replaced by Darwin’s natural selection.

  • Lamarck’s ideas contributed but lacked empirical support.

Theory of Natural Selection:

  • Darwin’s influential theory in biology.

  • Advantageous traits lead to survival and reproduction.

  • Drives species adaptation and evolution.

  • Explains diversity of life on Earth.



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