Overview
This lecture explains the major differences between prokaryotic and eukaryotic cells, highlighting their structure, classification, and relevance to health and biology.
Rings, Infections, and Treatment
- Ringworm is a fungal infection, not caused by a worm, and is treated with antifungal medication, not antibiotics.
- Antibiotics specifically target bacteria and do not work on fungi.
Prokaryotic vs. Eukaryotic Cells
- Prokaryotes include bacteria and archaea; all are unicellular (single-celled).
- Eukaryotes include protists, plants, animals, and fungi; may be unicellular or multicellular.
- Prokaryotic cells have no nucleus or membrane-bound organelles.
- Eukaryotic cells have a nucleus and various membrane-bound organelles (e.g., mitochondria, endoplasmic reticulum).
- Eukaryotic cells are generally larger and more complex than prokaryotic cells.
Common Structures in All Cells
- All cells have DNA (genetic material), ribosomes (for protein synthesis), cytoplasm (jelly-like fluid), and a cell membrane (regulates entry and exit of substances).
- Most prokaryotic cells have a cell wall; some eukaryotic cells (plants, fungi) have cell walls, but animal cells do not.
Classification and Vocabulary Use
- "Prokaryote" refers to the organism; its cell is called a prokaryotic cell.
- "Eukaryote" refers to the organism; its cell is called a eukaryotic cell.
- All living things are made of cells that are either prokaryotic or eukaryotic.
Key Terms & Definitions
- Prokaryote — unicellular organism without a nucleus or membrane-bound organelles (e.g., bacteria, archaea).
- Eukaryote — organism whose cells have a nucleus and membrane-bound organelles (e.g., plants, animals, fungi, protists).
- Antibiotic — substance that targets and kills bacteria.
- Antifungal — medication used to treat fungal infections.
- Ribosome — cell organelle that assembles proteins.
- Cytoplasm — jelly-like fluid inside cells.
- Cell membrane (plasma membrane) — barrier controlling what enters and exits the cell.
- Cell wall — rigid structure outside the cell membrane in some cells, providing support.
Action Items / Next Steps
- Practice comparing and contrasting prokaryotic and eukaryotic cells using key vocabulary.
- Review examples of organisms classified as prokaryotes and eukaryotes.