Important Theories in Biology for NEET Preparation
Biology encompasses various theories that explain the mechanisms of life. Understanding these theories is crucial for NEET aspirants.
1. Cell Theory
- All living organisms are composed of cells.
- The cell is the basic unit of life.
- All cells arise from pre-existing cells.
2. Theory of Evolution
- Proposed by Charles Darwin, it explains the diversity of life through natural selection.
- Organisms adapt to their environments over generations.
- Evidence includes fossil records and genetic similarities.
3. Germ Theory of Disease
- Established by Louis Pasteur and Robert Koch.
- States that many diseases are caused by microorganisms.
- Introduced the importance of hygiene and sterilization.
4. Theory of Inheritance
- Founded by Gregor Mendel, explaining how traits are passed from parents to offspring.
- Introduces concepts of dominant and recessive alleles.
- Forms the basis of modern genetics.
5. Endosymbiotic Theory
- Suggests that eukaryotic cells originated through symbiotic relationships.
- Key organelles like mitochondria and chloroplasts were once free-living prokaryotes.
- Explains the complexity of cellular structures.
6. Biogenesis vs. Abiogenesis
- Biogenesis: Life arises from pre-existing life.
- Abiogenesis: Life can originate from non-living matter.
- Key discussions in the origins of life on Earth.
7. Theory of Homeostasis
- Describes how biological systems maintain stability while adjusting to conditions.
- Essential for survival and normal functioning of organisms.
- Involves feedback mechanisms.
Understanding these theories provides a strong foundation in biology for NEET. Focus on key concepts and their implications for a comprehensive grasp of the subject.