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Cell Biology

197 lessons — Covers Introduction Imaging, Membranes Transport and Compartments Protein Sorting, and 20 more chapters.

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Introduction Imaging15 lessons

Chapter page

  1. Cell Theory and Historical Foundations
  2. Origins of Cellular Life
  3. Evolution of Metabolism
  4. Endosymbiotic Theory
  5. Prokaryotes vs. Eukaryotes
  6. Model Organisms
  7. Brightfield, Phase Contrast, and DIC Microscopy
  8. Fluorescence Microscopy
  9. Immunocytochemistry
  10. GFP Tagging
  11. Confocal Microscopy
  12. Super-Resolution Microscopy
  13. Transmission and Scanning Electron Microscopy (TEM & SEM)
  14. Flow Cytometry and FACS
  15. Differential Centrifugation

Membranes Transport14 lessons

Chapter page

  1. The Fluid Mosaic Model of the Plasma Membrane
  2. Membrane Lipids: Glycerophospholipids, Sphingolipids, and Cholesterol
  3. Cholesterol as a Fluidity Buffer
  4. Lipid Rafts and Membrane Microdomains
  5. Membrane Proteins: Integral, Peripheral, and Lipid-Anchored
  6. Membrane Permeability: What Crosses the Bilayer and Why
  7. Chemical vs. Electrical Gradients: The Electrochemical Gradient
  8. Simple Diffusion Across Membranes
  9. Facilitated Diffusion: Carriers and Channels
  10. Primary Active Transport: The Na⁺/K⁺ ATPase and Ca²⁺ ATPase
  11. Secondary Active Transport: Symport and Antiport
  12. Ion Channels: Voltage-, Ligand-, and Mechanically Gated
  13. The Resting Membrane Potential
  14. Patch-Clamp Electrophysiology: The Gigaseal and Single-Channel Recording

Compartments Protein Sorting11 lessons

Chapter page

  1. The Endomembrane System
  2. Evolutionary Origins of Internal Membranes
  3. Principles of Protein Sorting
  4. Nuclear Import
  5. Nuclear Export
  6. The Ran GTPase Cycle
  7. ER Targeting: Signal Peptide, SRP, and Sec61
  8. Soluble vs. Membrane Protein Insertion into the ER
  9. ER Protein Folding and Quality Control
  10. The Unfolded Protein Response
  11. Mitochondrial Protein Import

Vesicular Traffic15 lessons

Chapter page

  1. Vesicle Budding
  2. COPII: ER to Golgi Transport
  3. COPI: Retrograde Golgi to ER Transport
  4. Clathrin-Coated Vesicles
  5. Rab GTPases: Organelle Identity, Tethering, and Targeting
  6. SNARE Proteins and Membrane Fusion
  7. The ER-to-Golgi Secretory Pathway
  8. Golgi Organization and Cisternal Maturation
  9. Constitutive Secretion
  10. Regulated Secretion
  11. Endocytosis: Pinocytosis, Receptor-Mediated Endocytosis, and Phagocytosis
  12. LDL Receptor-Mediated Endocytosis and Cholesterol Homeostasis
  13. Endosome Maturation
  14. Lysosomes
  15. Autophagy

Cytoskeleton Motility16 lessons

Chapter page

  1. Actin Structure and Polymerization
  2. Actin Treadmilling
  3. Actin-Binding Proteins
  4. Myosins: Actin-Based Motor Proteins
  5. Muscle Contraction: The Sliding Filament Mechanism
  6. The Cytokinetic Contractile Ring
  7. Microtubule Structure
  8. Dynamic Instability
  9. MTOCs and Centrosomes
  10. Kinesins and Dyneins
  11. Cilia and Flagella
  12. Intermediate Filaments
  13. Filopodia
  14. Lamellipodia
  15. Focal Adhesions
  16. The Cell Migration Cycle

Cell Signaling13 lessons

Chapter page

  1. Modes of Cell Signaling
  2. Signal Amplification and Integration
  3. Intracellular Receptors (Steroid and Nuclear Receptors)
  4. Nitric Oxide Signaling
  5. GPCR Structure (Seven-Transmembrane Receptors)
  6. Heterotrimeric G Proteins
  7. cAMP–PKA Pathway
  8. IP3/DAG/Ca2+–PKC Pathway
  9. Receptor Tyrosine Kinases (RTKs)
  10. SH2 Domains and Phosphotyrosine Recognition
  11. Ras–MAPK Pathway
  12. PI3K–Akt Pathway
  13. Signal Termination

Cell Cycle Cell Death12 lessons

Chapter page

  1. Cell Cycle Overview
  2. Cyclins and Cyclin-Dependent Kinases (CDKs)
  3. G1–S Control and the Restriction Point
  4. G2–M Control (Cyclin B–Cdk1, Wee1/Cdc25)
  5. Spindle Assembly Checkpoint (SAC)
  6. Mitosis Mechanics: The Spindle and Its Microtubules
  7. Cohesin and Separase
  8. Cytokinesis and the Actomyosin Ring
  9. Apoptosis vs. Necrosis
  10. Intrinsic (Mitochondrial) Apoptosis Pathway
  11. Extrinsic (Death Receptor) Apoptosis Pathway
  12. The Caspase Cascade

Cancer Biology9 lessons

Chapter page

  1. Benign vs. Malignant Tumors
  2. Multistep Tumorigenesis
  3. Proto-oncogenes and Oncogenes
  4. Tumor Suppressor Genes
  5. p53: The Central Stress-Response Tumor Suppressor
  6. The Retinoblastoma Protein (Rb)
  7. BRCA1 and BRCA2: Homologous Recombination Caretakers
  8. The Hallmarks of Cancer
  9. Telomerase and Replicative Immortality

ECM Cell Junctions12 lessons

Chapter page

  1. Extracellular Matrix: Overview
  2. Collagen
  3. Elastin
  4. Proteoglycans and Glycosaminoglycans
  5. Fibronectin and Laminin
  6. Integrins
  7. Focal Adhesions
  8. Hemidesmosomes
  9. Tight Junctions
  10. Adherens Junctions
  11. Desmosomes
  12. Gap Junctions

Information Flow18 lessons

Chapter page

  1. Chromatin
  2. Euchromatin vs Heterochromatin
  3. Epigenetic Regulation
  4. Eukaryotic DNA Replication
  5. Mismatch Repair
  6. Base Excision Repair
  7. Double-Strand Break Repair
  8. RNA Polymerases
  9. Promoters, Enhancers, and Transcription Factors
  10. 5′ Capping
  11. 3′ Polyadenylation
  12. RNA Splicing
  13. Alternative Splicing
  14. Translation
  15. Protein Folding
  16. Phosphorylation
  17. Glycosylation
  18. Ubiquitination

Modern Techniques13 lessons

Chapter page

  1. Recombinant DNA Technology
  2. Polymerase Chain Reaction (PCR)
  3. Reverse Transcription Quantitative PCR (RT-qPCR)
  4. Southern Blot
  5. Northern Blot
  6. Western Blot
  7. SDS-PAGE (SDS-Polyacrylamide Gel Electrophoresis)
  8. RNA Interference (RNAi)
  9. CRISPR-Cas9 Genome Editing
  10. Genomics
  11. Transcriptomics and RNA-Seq
  12. Proteomics
  13. Bioinformatics and Data Integration

Reference5 lessons

Chapter page

  1. Cytoskeleton Comparison (Actin, Microtubules, Intermediate Filaments)
  2. Experimental Methods Comparison (Microscopy, Flow, PCR, Blots, RNA-Seq, CRISPR)
  3. Protein Sorting Map (Nucleus, ER, Mitochondria, Lysosome, Peroxisome)
  4. Signaling Pathway Map (GPCR-cAMP, GPCR-IP3/DAG, RTK-Ras/MAPK, PI3K/Akt)
  5. Vesicle Coat Map (COPII, COPI, Clathrin)

Advanced: Introduction & Imaging5 lessons

Chapter page

  1. 01 — Cell Theory and Evolution
  2. 04 — Light Microscopy
  3. 05 — Fluorescence and Confocal Microscopy
  4. 07 — Electron Microscopy
  5. 08 — Cell Isolation and Flow Cytometry

Advanced: Membranes & Transport3 lessons

Chapter page

  1. 2.1 Membrane Composition and the Fluid Mosaic Model
  2. 2.2 Membrane Proteins and Permeability
  3. 2.3 Passive and Active Transport

Advanced: Protein Sorting3 lessons

Chapter page

  1. Endomembrane System and Protein Sorting Principles
  2. Nuclear Transport — The Ran Cycle
  3. ER Translocation and Mitochondrial Import

Advanced: Vesicular Traffic5 lessons

Chapter page

  1. Vesicle Coats: COPII, COPI, and Clathrin
  2. Vesicle Budding and Scission
  3. Vesicle Targeting, Tethering, and SNARE-Mediated Fusion
  4. The Secretory Pathway and Endocytosis
  5. Endosomes, Lysosomes, and Autophagy

Advanced: Cytoskeleton & Motility5 lessons

Chapter page

  1. 01 — Actin: Structure, Polymerization, and Dynamics
  2. 02 — Myosin and Muscle Contraction
  3. 03 — Microtubules: Structure and Dynamic Instability
  4. 04 — Kinesin, Dynein, and Intracellular Transport
  5. 05 — Intermediate Filaments and Cell Migration

Advanced: Cell Signaling5 lessons

Chapter page

  1. 6.1 Signaling Principles and Intracellular Receptors
  2. 6.2 GPCRs and the cAMP Signaling Pathway
  3. 6.3 IP3/DAG/Ca²⁺ Signaling and GPCR Diversity
  4. 04 — RTKs and the Ras-MAPK Pathway
  5. 05 — PI3K-Akt Pathway and Signal Termination

Advanced: Cell Cycle & Cell Death3 lessons

Chapter page

  1. 01 — Cell Cycle Phases, Cyclins, and Cdks
  2. 02 — Checkpoints and Mitosis
  3. 03 — Apoptosis: Intrinsic and Extrinsic Pathways

Advanced: Cancer Biology3 lessons

Chapter page

  1. 01 — Cancer Foundations: Clonal Evolution, Oncogenes, and Tumor Suppressors
  2. 02 — Hallmarks of Cancer
  3. 03 — Telomeres, Cancer, and Metastasis

Advanced: Extracellular Matrix & Cell Junctions3 lessons

Chapter page

  1. ECM Components — Collagen, Elastin, Proteoglycans, and Adhesive Glycoproteins
  2. Integrins, Focal Adhesions, and Hemidesmosomes
  3. Cell Junctions — Tight, Adherens, Desmosome, and Gap Junctions

Advanced: Information Flow: DNA to Protein5 lessons

Chapter page

  1. Chromatin, Epigenetics, and Genome Organization
  2. DNA Replication
  3. DNA Repair
  4. Transcription and RNA Processing
  5. Translation and Post-Translational Modifications

Advanced: Modern Techniques4 lessons

Chapter page

  1. 11.1 Recombinant DNA and PCR
  2. 11.2 RT-PCR, qPCR, and Blotting
  3. 11.5 Genomics, Transcriptomics, and Proteomics
  4. 11.6 Systems Biology and Experimental Design