Cell Structure and Functions, Animation

Key Takeaways

• The plasma membrane is a phospholipid bilayer with embedded proteins that controls substance traffic and enables cell communication.
• Membrane proteins serve diverse roles including receptors, ion channels, adhesion molecules, enzymes, and surface antigens for cell identity.
• The nucleus houses DNA for replication and transcription, with nuclear pores regulating material exchange and the nucleolus producing ribosomes.
• The rough ER synthesizes secretory and transmembrane proteins, while smooth ER produces lipids and stores calcium for cellular processes.
• The Golgi apparatus modifies proteins post-translationally and sorts them via signal sequences to destinations like the plasma membrane or lysosomes.
• Lysosomes digest macromolecules using acid-activated hydrolases, playing key roles in recycling and immune defense in white blood cells.
• Mitochondria generate energy through cellular respiration, with the citric acid cycle in the matrix and oxidative phosphorylation on cristae folds.
• The cytoskeleton, composed of microfilaments, intermediate filaments, and microtubules, supports cell structure, division, and movement of organelles and cilia.