Cells and their Organelles You will be able to understand how the cell is structured, designed, and grows EQ: What do all living things have in common? All life forms from bacteria to the giant blue whale are comprised of cells Cells make up the smallest “unit” of life. All life is comprised of cells as well know it. What does all life have in common? (Modern Cell Theory) 1. All living things are made of cells 2. Cells are the base unit of all functions and design in living things 3. All cells are produced by other living cells PROBLEMS: Cant explain viruses Cant explain where first cell came from How are cells structured? Prokaryote vs. Eukaryote Prokaryote- (bacteria) ; simple design and very small. No special parts on the inside; but does contain DNA and RNA for replication Eukaryote- (multi-celled organisms) Cells much larger and contain specialized parts: organelles- parts of a cell which have a SPECIFIC FUNCTION! How do Cells “Know” when to Divide? Cell growth limited to processes of Osmosis and Diffusion Osmosis is the ability of water to move across cell membrane Diffusion is the ability of a gas (oxygen and CO2 to move across cell membrane Both are PASSIVE TRANSPORT methods (no energy needed) When Osmosis and Diffusion no longer “work” signals cell to divide Mitosis: Cell Division G1 Stage: Cytoplasm expands and organelles double S Stage ( Synthesis Stage): DNA in Cell doubles preparing for Cell Division G2 Stage: Cell undergoes Mitosis; Normal Cell Function Stops and Cell Divides Mitosis 6 Stages Interphase (G2)- Cell Function Normal (Cell grows) Prophase- Cell Function stops- Nucleus disappears, Centrioles and Spindle Fibers form, Chromosomes appear Metaphase- Chromosomes line up in Middle Anaphase- Chromosomes “rip” apart and move to opposite ends Telophase- Daughter Cells divide, (CYTOKENISIS) Nucleus reappears, Spindle Fibers, Chromosomes and Centrioles disappear Interphase (G 1 )- Cell goes back to normal function and grows What is Cancer? Cancer is simply when cells get “stuck” into the Synthesis and G2 of the cell cycle Cells continually divide and stop functioning normally, as a result organ stops functioning normally Cells can then break off a travel to other locations within the body, causing the cancer to SPREAD Cancer has 4 stages, Stage 1 and 2 cancer is “isolated”. Has not gotten past lymph nodes. Stage 3 and 4 Cancer has gotten into lymph nodes and has grown beyond original location. EUKARYOTE CELLS (Plants and Animals) Cell Wall – rigid wall of material located outside the cell membrane. Found in all plants cells, job is to support structure of plant. Not found in animal cells (except bacteria and some protists) “Brick wall of cell” Eukaryote Cells Cell Membrane- Outer edge of cell; controls what goes in and out of cell. Gatekeeper of Cell Eukaryote Cells Nucleus- Controls most functions of cell and the organelles Brain of the cell Eukaryote Cells Nuclear Membrane; controls what enters and leaves nucleus of cell; surrounds nucleus Bouncer of Cell Eukaryote Cells Chromatin- genetic material of cell; tells cell what sort of cell it becomes as well as making up its DNA material: found in the nucleus Blueprints of Cell Eukaryote Cells Mitochondria- Where cellular respiration occurs; (where food is burned in cell) provides energy to the cell. Found in cytoplasm Power-plants of cell Eukaryote Cells Endoplasmic Reticulum (E.R.) network of passage ways within cell to transport material and energy. Found in cytoplasm Roads of the Cell Eukaryote Cells Ribosome- specializes parts of cell that make proteins for the cells. Found in the E.R. of the cytoplasm and made by the nucleolus Chef of the Cell Eukaryote Cells Nucleolus- “Dark spot” in Nucleus of the cell. Makes Ribosomes for the cell Dark side of Cell Eukaryote Cells Golgi Apparatus /(Body)- found in cytoplasm. Organelles that are the carrying devices for food and other material throughout the cell UPS of the cell Eukaryote Cells Chloroplasts- found commonly in plant cells cytoplasm. Organelles that convert light into food energy “Greenies of the cell” Chloroplasts Eukaryote Cell Vacuole- Storage area in a cell’s cytoplasm; Larger in plants than animal cells used for water and waste storage Trashcan of cell Eukaryote Cell Lysosome- organelle that cleans out cytoplasm and destroys worn out organelles Janitor of Cell with Lysol Eukaryote Cell Centriole- only in animal cells: where spindle fibers attach during cell replication Anchor of cell Eukaryote Cells Spindle fibers- “strings” which attach to chromosomes during cell replication process. Found in cytoplasm and only visible during cell replication Strings of Cell Eukaryote Cell Cytoplasm- “jam like liquid” found within the cell membrane. Holds everything in place and is material through which osmosis and diffusion occur Jam of Cell