Organelles and Cell Specialization
This lesson connects molecular mechanisms, cell behavior and biological evidence. Instead of memorizing isolated terms, follow what changes, what is measured, where the process occurs and why the outcome matters to a living system.
Big idea
The nucleus stores DNA, while ribosomes translate RNA into polypeptides. Rough ER, smooth ER, Golgi apparatus and vesicles synthesize, modify and route cell products.
Learning goals
- Nucleus and ribosomes: The nucleus stores DNA, while ribosomes translate RNA into polypeptides.
- Endomembrane system: Rough ER, smooth ER, Golgi apparatus and vesicles synthesize, modify and route cell products.
- Energy organelles: Mitochondria make most ATP in aerobic cells, and chloroplasts capture light energy in photosynthetic cells.
- Cytoskeleton and movement: Protein filaments maintain shape, organize organelles and enable intracellular or whole-cell movement.
- Cell specialization: Different patterns of gene expression and organelle abundance adapt cells for particular functions.
Core concepts
1. Nucleus and ribosomes
The nucleus stores DNA, while ribosomes translate RNA into polypeptides.
Observation or application: A cell expressing many proteins uses nuclear information and abundant ribosomes.
2. Endomembrane system
Rough ER, smooth ER, Golgi apparatus and vesicles synthesize, modify and route cell products.
Observation or application: A secreted protein moves from rough ER through Golgi to a vesicle.