Cells Intro Notes PDF

# Teacher Notes: Cells Intro ## The Wacky History of Cell Theory - **Robert Hooke (1665)** used a compound microscope to view a thin slice of cork and first named the tiny compartments *cells* due to their resemblance to the rooms monks lived in. - **Anton van Leeuwenhoek (1674)** built his own...

# Teacher Notes: Cells Intro ## The Wacky History of Cell Theory - **Robert Hooke (1665)** used a compound microscope to view a thin slice of cork and first named the tiny compartments *cells* due to their resemblance to the rooms monks lived in. - **Anton van Leeuwenhoek (1674)** built his own microscopes and was the first to see living *animalcules* under a microscope. He published a whole book of his observations of living microbes. - **Schleiden (1839)** concluded that *"all plants are made of cells"* - **Schwann (1836)** concluded that *"all animals are made of cells"* - **Virchow (1855)** stated that *"all cells come from pre-existing cells"* ## Cell Theory - All living things are composed of cells - Cells are the basic unit of structure and function in living things - New cells are produced from existing cells ## 2 Cell Types ### Prokaryotic * **"pro" = before** * **"kary" = nugget/ "nut" - nucleus** (DNA) * Found in: bacteria * **Characteristics:** * Single cells: unicellular * Smaller * No nucleus * No membrane bound organelles * Only membrane is the cell membrane ### Eukaryotic * **"eu" = true** * **"kary" = nugget/"nut" - nucleus** (DNA) * Found in: all organisms except bacteria (Protists, Fungi, Plants, Animals) * **Characteristics:** * Single cells or multicellular organisms * 10-100x larger than bacteria * Nucleus with DNA in nuclear membrane * Many Organelles surrounded by membrane **All cells have these** - Cell membrane - Cytoplasm - DNA ## Prokaryotes vs. Eukaryotes ### Prokaryotes 1. No nucleus - free floating DNA 2. No membrane bound organelles 3. Bacteria - example 4. Smaller 5. Unicellular 6. Simplest cells - usually asexual reproduction only ### Eukaryotes **Cell Types:** - Structures 1. DNA 2. Cytoplasm 3. Ribosomes 4. Cell membrane 5. Cytoskeleton 1. Has nucleus with DNA enclosed 2. Has membrane bound organelles 3. All organisms except bacteria 4. 10-100x larger 5. Unicellular of multicellular 6. More complex cells - Asexual or sexual reproduction