Cell Types and Subcellular Structures
Lecture 2: 4BBY1030 Cell Biology & Neuroscience
Instructor: Dr. Clemens Kiecker
Learning Outcomes
- Explain the concept of the cell.
- Classify different types of cells: prokaryotes, eukaryotes, bacteria, archaea, fungi, plants, animals.
- Outline the organization of eukaryotic cells and describe major features and organelles.
Chapter 1: The Concept of the Cell
Cell Theory
- Our bodies consist of approximately 37 trillion cells.
- Pioneers: Robert Hooke, Matthias Schleiden, Theodor Schwann, Rudolf Virchow.
- Key Principles:
- All living organisms consist of one or more cells.
- The cell is the basic unit of life.
- Cells arise from existing cells by division.
True or False
- All cells are surrounded by a plasma membrane.
- Not all cells have a cell wall.
- All cells contain genetic material as DNA.
- Not all cells have DNA in a nucleus.
- All cells perform metabolism.
- Not all cells can move.
Chapter 2: Types of Cells
Prokaryotes vs. Eukaryotes
- Prokaryotes: No nucleus, always single-celled.
- Bacteria (includes cyanobacteria).
- Archaea: thrive in extreme environments.
- Eukaryotes: Have a nucleus, can be single or multi-cellular.
- Plants, animals, fungi, protozoans.
Evolution of Cells
- Overview of the evolutionary pathways of cell types.
Chapter 3: Cellular Organization, Organelles, and Subcellular Structures
The Cell (Plasma) Membrane
- Bilayer of phospholipids, cholesterol, and proteins.
- Roles: Barrier, communication, import/export, electrical capacitor.
- Dynamic structure including lipid rafts.
The Cytoskeleton
- Made of protein fibers: actin filaments, intermediate filaments, microtubules.
- Functions: Shape maintenance, cell division, motility, intracellular movement.
The Cytoplasm (Cytosol)
- Aqueous solution with proteins, tRNAs, ribosomes, and inclusion bodies.
The Nucleus
- Surrounded by a double-layered nuclear envelope.
- Contains DNA, nucleoplasm, and nucleolus (site of ribosome synthesis).
- Functions in RNA synthesis and processing.
Endoplasmic Reticulum (ER)
- Network of membrane vesicles continuous with the nuclear membrane.
- Rough ER: Protein synthesis.
- Smooth ER: Lipid synthesis, detoxification, glucose release.
Golgi Apparatus
- Stack of flattened vesicles.
- Modifies proteins for secretion or transmembrane use.
Mitochondria
- Oval-shaped, double-membraned.
- Functions: Respiration, Krebs cycle, heat production, calcium storage, apoptosis.
Lysosomes
- Found in animal cells, degrade proteins and organelles.
- Acidic environment suitable for enzymes.
Peroxisomes
- Degrade fatty acids, detoxify compounds.
- Catalase enzyme neutralizes hydrogen peroxide.
Recommended Reading
- Pollard, Earnshaw, Lippincott-Schwartz, Johnson, Pollard (2017) "Cell Biology" 3rd ed.
- Note: Use as a supplement, not required to read fully.
Contact Information
Institution
- Kings College London. All rights reserved.