#🔬 Cell Structure & Function: Your AP Bio Night-Before Guide 🚀

Hey AP Bio superstar! Let's get you feeling confident for tomorrow. This guide is designed to be your quick, high-impact review, focusing on the most crucial cell concepts. Let's dive in!

#1. Subcellular Components & Organelles

These are the workhorses of the cell, and understanding their functions is KEY. They are not just isolated structures; they work together to keep the cell alive. Let's break down the most important ones:

#1.1. Ribosomes 🧬

• Function: Protein synthesis. They read mRNA and assemble amino acids into polypeptides.
• Composition: Ribosomal RNA (rRNA) and proteins.
• Significance: Found in ALL life forms, showing common ancestry. 👨‍👩‍👧‍👦

#1.2. Endoplasmic Reticulum (ER) 🚕

• Function: Mechanical support, intracellular transport, and compartmentalization.
• Types:
  • Rough ER: Studded with ribosomes; involved in protein synthesis and modification.
  • Smooth ER: Detoxification, lipid synthesis, and maintaining cellular homeostasis.

#1.3. Golgi Complex 📦

• Structure: Flattened membrane sacs called cisternae.
• Function: Protein modification (folding, glycosylation), sorting, and packaging for transport.
• Analogy: Think of it as the cell's post office, processing and shipping proteins.

#1.4. Mitochondria 💨

• Function: ATP production (cellular respiration).
• Structure: Double membrane; inner membrane is highly folded (cristae) to increase surface area.
• Key Processes:
  • Glycolysis: First step, occurs in cytoplasm (common ancestry!).
  • Citric Acid/Krebs Cycle: In the mitochondrial matrix.
  • Oxidative Phosphorylation: In the inner membrane, using the electron transport chain.
• Unique Feature: Contains its own DNA. 🧬

#1.5. Lysosomes 🚮☠️

• Function: Contain hydrolytic enzymes for breaking down cellular waste and worn-out parts.
• Role: Apoptosis (programmed cell death).

#1.6. Vacuoles 🌱

• Function: Storage of macromolecules, waste, and water.
• Plant Cells: Large central vacuole for water retention and turgor pressure (rigidity).

#1.7. Chloroplasts ⚡️

• Function: Photosynthesis (capturing solar energy and making sugars).
• Structure: Double membrane, thylakoids (flattened sacs).
• Key Processes:
  • Light-dependent reactions: In the grana, produce ATP and NADPH.
  • Light-independent reactions (Calvin Cycle): In the stroma, fix carbon to make sugars.