Examples of prokaryotic cells

📚 Quick Study Guide

• 🧬 Definition: Prokaryotic cells are cells without a nucleus or other membrane-bound organelles.
• 🦠 Domains: They belong to two domains: Bacteria and Archaea.
• 📏 Size: Generally smaller than eukaryotic cells, typically ranging from 0.5 to 2 μm in diameter.
• 📝 Cell Wall: Most prokaryotic cells have a cell wall for protection and support. Bacterial cell walls contain peptidoglycan.
• 💍 DNA: DNA is usually a single circular chromosome located in the nucleoid region.
• ➕ Plasmids: Many prokaryotes also contain plasmids, small circular DNA molecules with extra genes.
• ⚙️ Ribosomes: They have ribosomes, but they are smaller (70S) than those found in eukaryotic cells (80S).
• ➗ Reproduction: Prokaryotes reproduce asexually through binary fission.
• 🌍 Examples: Common examples include bacteria like *Escherichia coli* (*E. coli*) and archaea like *Methanogens*.

Practice Quiz

1. Which of the following is a defining characteristic of prokaryotic cells?
   1. A. Presence of a nucleus
   2. B. Presence of membrane-bound organelles
   3. C. Absence of a nucleus
   4. D. Large cell size (over 100 μm)
2. To which domains do prokaryotic cells belong?
   1. A. Bacteria and Eukarya
   2. B. Archaea and Eukarya
   3. C. Bacteria and Archaea
   4. D. All three domains: Bacteria, Archaea, and Eukarya
3. What is the typical size range of prokaryotic cells?
   1. A. 10-100 μm
   2. B. 0.5-2 μm
   3. C. 50-500 μm
   4. D. 100-1000 μm
4. What is peptidoglycan?
   1. A. A type of membrane-bound organelle
   2. B. A component of eukaryotic cell walls
   3. C. A component of bacterial cell walls
   4. D. A type of plasmid
5. Where is the DNA located in a prokaryotic cell?
   1. A. Nucleus
   2. B. Endoplasmic reticulum
   3. C. Golgi apparatus
   4. D. Nucleoid region
6. How do prokaryotes typically reproduce?
   1. A. Meiosis
   2. B. Mitosis
   3. C. Binary fission
   4. D. Sexual reproduction
7. Which of the following is an example of a prokaryotic organism?
   1. A. Mushroom
   2. B. Amoeba
   3. C. *Escherichia coli* (*E. coli*)
   4. D. Human cell