Overview
This lecture provides an overview of the main cell organelles and their functions, focusing on content relevant for first-year nursing anatomy and physiology (anaphy) classes.
Cell Membrane
- The cell membrane acts as a selective barrier controlling the movement of substances in and out of the cell.
- It maintains cell integrity and helps with communication and signaling.
Nucleus
- The nucleus stores genetic material (DNA) and coordinates cellular activities like growth and reproduction.
- It is surrounded by a nuclear envelope that separates it from the cytoplasm.
Cytoplasm
- The cytoplasm is the fluid where organelles are suspended and many metabolic reactions occur.
- It supports and protects cellular structures.
Mitochondria
- Mitochondria are the cell's powerhouses, producing energy (ATP) through cellular respiration.
- They are numerous in cells that require a lot of energy.
Endoplasmic Reticulum (ER)
- The rough ER is studded with ribosomes and synthesizes proteins.
- The smooth ER lacks ribosomes and synthesizes lipids and detoxifies substances.
Golgi Apparatus
- The Golgi apparatus modifies, sorts, and packages proteins and lipids for storage or transport out of the cell.
Lysosomes
- Lysosomes contain digestive enzymes that break down waste materials and cellular debris.
- They help protect the cell by digesting harmful invaders.
Ribosomes
- Ribosomes are the sites of protein synthesis, found either free in the cytoplasm or attached to the rough ER.
Other Organelles
- Centrioles play a role in cell division.
- Peroxisomes break down fatty acids and neutralize harmful substances.
Key Terms & Definitions
- Organelle — Specialized structure within a cell that performs a specific function.
- Cytoplasm — Jelly-like substance inside the cell that holds organelles.
- ATP (Adenosine Triphosphate) — Main energy currency of the cell.
- Ribosome — Structure that assembles proteins from amino acids.
Action Items / Next Steps
- Review diagrams of cell organelles and their functions.
- Prepare for a quiz on cell structures for the next class.