Overview
This lecture focuses on the main organelles found in cells, their functions, and key characteristics relevant for understanding cell biology.
Major Cell Organelles
- The cell membrane controls what enters and exits the cell.
- The nucleus stores the cell’s genetic material (DNA) and directs activities.
- Mitochondria are the site of cellular respiration and energy (ATP) production.
- Ribosomes synthesize proteins needed by the cell.
- The endoplasmic reticulum (ER) transports materials throughout the cell; rough ER has ribosomes, smooth ER does not.
- Golgi apparatus packages and ships proteins and other molecules.
- Lysosomes contain enzymes that break down waste and cellular debris.
- Vacuoles store materials like water, nutrients, and waste; larger in plant cells.
- Chloroplasts (in plant cells) conduct photosynthesis to make glucose.
- The cell wall (in plant cells) provides structure and protection outside the cell membrane.
- Cytoplasm is the jelly-like substance that fills the cell and holds organelles in place.
Differences Between Plant and Animal Cells
- Plant cells have chloroplasts, cell walls, and large central vacuoles, which animal cells lack.
- Animal cells have multiple small vacuoles, while plant cells have a single large vacuole.
Key Terms & Definitions
- Organelle — specialized structure within a cell that performs a specific function.
- Cell Membrane — barrier that controls movement of substances in and out of the cell.
- Nucleus — organelle containing DNA; controls cell functions.
- Mitochondria — powerhouse of the cell; site of ATP production.
- Ribosome — site of protein synthesis.
- Endoplasmic Reticulum (ER) — network for transporting materials; rough ER has ribosomes, smooth ER does not.
- Golgi Apparatus — packages and distributes proteins.
- Lysosome — contains digestive enzymes for breaking down materials.
- Vacuole — storage structure in cells.
- Chloroplast — site of photosynthesis in plant cells.
- Cell Wall — rigid structure for support in plant cells.
- Cytoplasm — gel-like fluid holding organelles.
Action Items / Next Steps
- Review all 44 Gimkit questions about cell organelles.
- Study differences between plant and animal cells.
- Memorize the function of each organelle.