🌟 Lesson 14: Prokaryotic vs. Eukaryotic Cells
🔰 Introduction
All living things are made of cells. But not all cells are the same!
Cells come in two main types:
✅ Prokaryotic cells (like bacteria)
✅ Eukaryotic cells (like plants, animals, fungi, and protozoa)
Both types of cells share some common features:
- They both have DNA (genetic material)
- They both have a plasma membrane
- They both have ribosomes (for making proteins)
So what’s the difference? Let’s explore!
🧬 Structure of Prokaryotic Cells
Let’s understand the word first:
“Pro” means before and “karyon” means nucleus.
So, Prokaryotic = Before nucleus ➡️ No true nucleus!
🔍 Key Features of Prokaryotic Cells:
| Feature | Description |
| Size | Very small (2 to 8 µm) – about 10 times smaller than a eukaryotic cell. Think of a grain of sand compared to a marble. |
| Nucleus? | ❌ No true nucleus. DNA is found floating in a region called the nucleoid. |
| Organelles? | ❌ No membrane-bound organelles (like mitochondria, ER, Golgi, etc.) |
| Cytoplasm | Just one open space — no compartments inside. |
| Ribosomes | Present, but smaller than those in eukaryotic cells. Used for protein synthesis. |
🧠 Mnemonic to Remember Prokaryotic Cell Features
“NORM CRP”
- N — No nucleus
- O — Organelles (membrane-bound) absent
- R — Ribosomes (small)
- M — Minimal internal structure
- C — Cell wall (with peptidoglycan)
- R — Reproduce by binary fission
- P — Pili/Plasmids possible
➡️ How It Helps: Mnemonics are like memory tricks. “NORM CRP” gives you a checklist to remember the core features of prokaryotic cells during tests or explanations!