Cell Biology PDF

Organelle Functions: 1. Nucleus: DNA storage, transcription 2. Mitochondria: Energy production (ATP) 3. Endoplasmic Reticulum (ER): Protein synthesis, transport 4. Ribosomes: Protein synthesis 5. Lysosomes: Cellular digestion, recycling 6. Golgi Apparatus: Protein modificati...

Organelle Functions: 1. Nucleus: DNA storage, transcription 2. Mitochondria: Energy production (ATP) 3. Endoplasmic Reticulum (ER): Protein synthesis, transport 4. Ribosomes: Protein synthesis 5. Lysosomes: Cellular digestion, recycling 6. Golgi Apparatus: Protein modification, packaging 7. Cytoskeleton: Structural support, movement, division 8. Plasma Membrane: Cell signaling, transport, protection 9. Chloroplasts (in plant cells): Photosynthesis 10. Peroxisomes: Breakdown of fatty acids, amino acids Organelle Interactions: 1. Protein Synthesis: Ribosomes, ER, Golgi Apparatus 2. Cellular Respiration: Mitochondria, ER 3. Cell Signaling: Plasma Membrane, Cytoskeleton 4. Photosynthesis (in plant cells): Chloroplasts, Mitochondria Cytoskeleton Functions: 1. Movement: Microtubules, microfilaments, intermediate filaments 2. Structural support 3. Cell division Endosymbiotic Theory: Evidence: 1. Mitochondrial DNA 2. Chloroplast DNA 3. Similarity between mitochondrial/chloroplast membranes and bacterial membranes 4. Presence of ribosomes in mitochondria/chloroplasts Support: 1. Mitochondria/chloroplasts evolved from ancient bacteria 2. Engulfment and symbiosis led to development of eukaryotic cells Increased Organelles in Specialized Cells: 1. Muscle cells: More mitochondria for energy production 2. Nerve cells: More mitochondria and ER for neurotransmitter synthesis 3. Plant cells: More chloroplasts for photosynthesis 4. Pancreatic cells: More ER and Golgi Apparatus for insulin production Cell Classification: 1. Bacteria: Prokaryotic, no nucleus, single-celled 2. Prokaryotic cells: No nucleus, single-celled (e.g., bacteria, archaea) 3. Eukaryotic cells: Nucleus, membrane-bound organelles, single or multicellular Requirements for a Cell: 1. Plasma membrane 2. Cytoplasm 3. Genetic material (DNA/RNA) 4. Metabolic processes Organelles Involved in Protein Synthesis: 1. Ribosomes 2. Endoplasmic Reticulum (ER) 3. Golgi Apparatus Missing Organelle and Homeostasis: Depends on the organelle: 1. Missing mitochondria: Energy production impaired 2. Missing lysosomes: Cellular digestion/recycling impaired 3. Missing ER: Protein synthesis/transport impaired 1. Identifying Solutions: · Hypertonic: Higher solute concentration outside the cell (shrinks) · Isotonic: Equal solute concentration inside and outside the cell (no change) · Hypotonic: Lower solute concentration outside the cell (swells) 2. Analyzing Osmosis Data: Factors affecting osmosis rate: · Concentration gradient · Surface area · Temperature · Pressure Relationships: · Increased concentration gradient → Faster osmosis · Increased surface area → Faster osmosis · Increased temperature → Faster osmosis · Increased pressure → Slower osmosis 3. Identifying Cell Environments: Given an image of a cell: · Hypertonic: Cell shrinks, membrane pulls away from wall · Hypotonic: Cell swells, membrane stretches · Isotonic: Cell remains unchanged 4. Active vs. Passive Transport: Active Transport: · Requires energy (ATP) · Moves molecules against concentration gradient · Examples: Pumping ions, transporting large molecules Passive Transport: · No energy required · Moves molecules down concentration gradient · Examples: Diffusion, osmosis, facilitated diffusion 5. Measuring Active Transport: · Concentration gradient changes · ATP consumption · Ion or molecule movement against concentration gradient · Use of transport proteins/inhibitors 6. Facilitated Diffusion vs. Simple Diffusion: Facilitated Diffusion: · Uses transport proteins · Faster rate · Specific molecules Simple Diffusion: · No transport proteins · Slower rate · Non-specific molecules 7. Macromolecules, Polymers, and Monomers: · Macromolecules: Large molecules (proteins, carbohydrates, nucleic acids) · Polymers: Long chains of monomers (e.g., proteins, DNA) · Monomers: Small building blocks (amino acids, sugars, nucleotides) Additional key concepts: · Selective permeability · Transport proteins (channel, carrier) · Osmotic pressure · Tonicity