Examining Prokaryotic Cells

1. What types of organisms are prokaryotic?
   • Bacteria and Archaea are the two domains of prokaryotic organisms.
2. What structures are found in a eukaryotic cell that will not be visible in a prokaryotic cell?
   • Nucleus
   • Membrane-bound organelles (e.g., mitochondria, Golgi apparatus, endoplasmic reticulum)
   • Linear chromosomes instead of circular DNA
   • Larger ribosomes (80S in eukaryotes vs. 70S in prokaryotes)
3. Virtual Microscope Exercise
   • The virtual microscope exercise requires interaction with an online tool to observe a prokaryotic specimen.
   • Identify and sketch the specimen at different magnifications (10x, 40x, and 100x), labeling visible structures.

Exercise 2: Examining Eukaryotic Cells

Plant Cells

1. Three ways plant cells differ from animal cells:
   • Presence of a cell wall (provides structure and support)
   • Presence of chloroplasts (used in photosynthesis)
   • Presence of a large central vacuole (stores water, nutrients, and waste)
2. Virtual Microscope Exercise
   • Examine two plant cell samples and sketch them under 4x, 10x, and 40x magnification, labeling visible structures.
3. What shape do most plant cells have? What structure maintains this shape?
   • Most plant cells have a rectangular or box-like shape due to the presence of a cell wall.
4. Which cellular components are present in these cells but not found in any other cell types?
   • Chloroplasts (used for photosynthesis)
   • Cell wall (made of cellulose)
   • Large central vacuole

Animal Cells

1. Virtual Microscope Exercise
   • Examine one animal cell and one human cell sample, then sketch under 4x, 10x, and 40x magnification.
2. What shape do most animal cells have? What structure maintains this shape?
   • Animal cells vary in shape but are generally rounded or irregular. The cytoskeleton (network of protein filaments) helps maintain their shape.
3. Which cellular components are present in these cells but not found in any other cell types?
   • Centrioles (used in cell division)
   • Lysosomes (contain digestive enzymes for breaking down waste)

Cells Review Questions

1. Describe how you would prepare a wet mount slide.
   • Place a small drop of water or stain on a clean glass slide.
   • Place the specimen in the liquid.
   • Gently place a cover slip over the specimen at an angle to avoid air bubbles.
   • Use a paper towel to remove excess liquid if necessary.
2. What characteristics do all cells have in common?
   • Cell membrane (plasma membrane)
   • Cytoplasm
   • Ribosomes (though they differ in size)
   • DNA or RNA as genetic material
3. What characteristics are common to all eukaryotic cells but not found in prokaryotic cells?
   • Nucleus
   • Membrane-bound organelles
   • Larger ribosomes (80S)
   • More complex internal structure
4. Would you expect that all living cells contain mitochondria? Explain.
   • No, not all living cells contain mitochondria.
   • Prokaryotic cells (bacteria and archaea) do not have mitochondria.
   • Some anaerobic eukaryotes also lack mitochondria and rely on other forms of energy production.
5. Describe as many differences as you can between plant and animal cells at a cellular level. Do any of these differences relate to organismic differences between plants and animals? Explain.
   • Plant Cells:
     • Have cell walls (structural support)
     • Contain chloroplasts (photosynthesis)
     • Have a large central vacuole
     • Lack centrioles
   • Animal Cells:
     • No cell wall, only a flexible plasma membrane
     • No chloroplasts (cannot perform photosynthesis)
     • Have centrioles (involved in cell division)
     • Have lysosomes (digestive organelles)
   • Relation to Organismic Differences:
     • Plants are autotrophic (make their own food) due to chloroplasts.
     • Animals are heterotrophic and rely on consuming food for energy.
     • The cell wall in plants provides structure, allowing them to grow upright.
     • Animal cells’ flexibility allows for movement, unlike rigid plant cells.
6. How would you compare a protist cell to a human cheek cell in terms of complexity at the cellular level?
   • Protists (e.g., amoebas, paramecia) are unicellular but more complex than human cheek cells.
   • Protists must perform all life functions within a single cell (e.g., movement, digestion, reproduction).
   • Cheek cells are part of a multicellular organism and do not need to perform all life functions independently.
   • Some protists have cilia or flagella for movement, whereas cheek cells are stationary.

Start Your Cell Biology Journey Today!

Understanding the differences between prokaryotic and eukaryotic cells is key to unlocking the secrets of life. Whether you’re a student, educator, or science enthusiast, this lab exercise provides hands-on experience in identifying and analyzing cells under a virtual microscope.

🔬 Take Action Now!

• Dive deeper into cell biology by exploring real microscopic specimens.
• Test your knowledge by comparing plant, animal, and prokaryotic cells.
• Enhance your lab skills by mastering wet mount slide preparation.

Ready to explore the unseen world of cells? Open the virtual microscope and begin your journey into the building blocks of life!