Cell Structure and Function

Cell Structure and Function

• Cells are the fundamental units of life, exhibiting a complex organization.
• All cells share common features, including a plasma membrane, cytoplasm, and DNA.
• Prokaryotic cells (bacteria and archaea) are simpler, lacking a nucleus and membrane-bound organelles.
• Eukaryotic cells (plants, animals, fungi, and protists) are more complex, possessing a nucleus and various organelles.
• The plasma membrane regulates the passage of substances in and out of the cell.
• The cytoplasm contains various organelles with specific functions.
• The nucleus houses the cell's genetic material (DNA).
• Mitochondria are the powerhouse of the cell, responsible for energy production through cellular respiration.
• Ribosomes are the sites of protein synthesis.
• Endoplasmic reticulum (ER) facilitates protein and lipid synthesis.
• Golgi apparatus processes and packages proteins.
• Vacuoles and vesicles store and transport materials.
• Lysosomes contain digestive enzymes to break down waste.
• Chloroplasts (in plant cells) are responsible for photosynthesis.
• Cytoskeleton provides structural support and facilitates movement.

Cellular Processes

• Cellular respiration is the process by which cells convert glucose into ATP, the energy currency of the cell.
• Photosynthesis is the process plants and some other organisms use to convert light energy into chemical energy.
• Cellular division (mitosis and meiosis) is essential for growth, repair, and reproduction.
• Mitosis produces two identical daughter cells from a single parent cell.
• Meiosis produces four genetically diverse daughter cells (gametes) for sexual reproduction.
• DNA replication creates an exact copy of the DNA molecule.
• Gene expression, encompassing transcription and translation, controls the production of proteins.

Genetics

• DNA is the hereditary material that carries genetic information.
• Genes are segments of DNA that code for specific proteins.
• The structure of DNA is a double helix.
• RNA is involved in protein synthesis and other cellular processes.
• Mutations are changes in DNA sequence that can impact an organism.
• Mendelian genetics describes the inheritance of traits based on the principles of segregation and independent assortment.
• Chromosomes carry genetic material in the form of DNA.
• Genetic variations contribute to diversity in populations.
• Modern genetics studies the structure, function, and interaction of genes.
• DNA Technology enables manipulating DNA for various purposes.

Ecology

• Ecology studies interactions of organisms with their environment.
• Organisms interact with each other and their environment.
• Ecosystems are complex systems comprising of living organisms and abiotic components.
• Biodiversity represents the variety of life on Earth.
• Populations are groups of individuals of the same species.
• Communities are assemblages of populations of different species interacting.
• Energy flow through ecosystems follows trophic levels like producers, consumers, and decomposers.
• Nutrient cycles (e.g., carbon, nitrogen) are vital for maintaining ecosystem health.
• Climate change significantly impacts ecosystems globally.

Evolution

• Evolution is the process of change in the heritable characteristics of biological populations over successive generations.
• Natural selection is a key mechanism of evolution, driving adaptation of species to their environment.
• Genetic variations provide the raw material for natural selection to act upon.
• Common ancestry unites all living organisms.
• Speciation is the process by which new species arise.
• Fossil records contain evidence of past life.
• Comparative anatomy and molecular biology offer insights into evolutionary relationships.
• Adaptations enable organisms to survive and reproduce successfully.
• Evolution is supported by a wealth of evidence from multiple disciplines.