Genetics-And-Evolution-Concepts-Summary-And-Evolution-1
Mendel:
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Gregor Mendel is the father of modern genetics.
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Laws of Inheritance: Law of Segregation and Law of Independent Assortment.
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Traits are determined by discrete units called genes.
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Genes are inherited in a predictable manner.
Photosynthesis:
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Converts sunlight into chemical energy (glucose and oxygen).
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Occurs in chloroplasts with chlorophyll pigments.
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Essential for plant energy and oxygen production.
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Basis of food chains and oxygen levels on Earth.
Evolution - Origin of Universe:
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Big Bang theory: Universe started as a singularity.
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Rapid expansion created space, time, matter.
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Led to galaxy, star, and planet formation.
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Explains universe’s origin, structure, and expansion.
Origin of Earth:
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Earth formed 4.5 billion years ago.
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Developed layers: crust, mantle, core.
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Shaped by geological processes: tectonics, volcanism, erosion.
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Crucial for understanding life’s development.
Theory of Biogenesis:
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Living organisms arise from pre-existing life.
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Rejects spontaneous generation (life from non-life).
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Supported by experiments by Louis Pasteur.
Origin of Cellular Forms:
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Simple, single-celled organisms likely preceded complex life.
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RNA world hypothesis explores early life’s origin.
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Hydrothermal vent theories also considered.
Theories of Evolution:
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Darwin’s Theory of Natural Selection and Wallace’s theory.
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Organisms with advantageous traits survive and reproduce.
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Gradual change and adaptation over generations.
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Explains diversity and interconnectedness of life.
Criticism of Lamarck’s Theory:
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Lamarck proposed acquired traits inheritance.
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Replaced by Darwin’s natural selection.
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Lamarck’s ideas contributed but lacked empirical support.
Theory of Natural Selection:
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Darwin’s influential theory in biology.
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Advantageous traits lead to survival and reproduction.
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Drives species adaptation and evolution.
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Explains diversity of life on Earth.