Do Now What are cells? Why do we need them? List different types of cells that you know of… Objectives Describe how cells were discovered and named. Compare and contrast light microscopes vs. electron microscopes. Explain what is found in a basic cell. Cells Chapter 7 What are cells? Basic structural and functional unit of all living organisms! They come in all shapes and sizes Lets take a look… http://www.cellsalive.com/howbig.htm Cells! Egg cell How did we figure out cells even existed, what they looked like, what they do?... Nerve cell Bacteria cell Robert Hooke 1665- saw dead plant cells from cork, tree stems, roots and ferns using a light microscope Called them “cellulae” (small rooms) reminded him of the cubicles or cells where monks live Leeuwenhoek First person to observe living cells Made microscope with a magnification 10X that of Hooke’s- “Father of microscopes” Observed spirogyra and protists The “Cell Theory” Scientists expressed 3 main observations about cells: All living organisms are composed of one or more cells Cells are the basic units of structure and organization of all living organisms Cells come only from the reproduction of existing cells Technology is the key! Cells were discovered using MICROSCOPES! Compound Light Microscopes Uses visible light to produce magnified image. Maximum = 1,000x magnification Electron Microscopes Specimen must be dead Use magnets and electrons Allows much greater magnification Ex: Transmission Electron = up to 500,000x Electron Microscopes Transmission Electron Microscope Electrons are sent through a specimen Scanning Electron Microscope Electrons are sent over the surface of a speciment. Basic Parts of any Cell DNA/RNA Needs some type of genetic information! Plasma membrane Cell’s outer boundary that acts as a barrier Cytoplasm Region of cell that includes fluid, cytoskeleton and all organelles except the nucleus Cytosol- part of cytoplasm that included molecules and small particles but not organelles Control Center Contains a cell’s DNA Nucleus- membrane- bound structure in eukaryotes Nucleoid- region of DNA in prokaryotes Prokaryotic vs. Eukaryotic Organisms can be made up of either prokaryotic or eukaryotic cells. Prokaryotic Cells… Do not have a distinct nucleus No membranebound organelles Ex: bacteria (many scientists think that prokaryotes are similar to the first EVER organisms on Earth) Eukaryotic Cells… Contain a nucleus Contain membrane-bound organelles Makes up most multicellular organisms Ex: US, plants, animals, etc. (also some unicellular organisms like algae and yeast) Lets Review! Who discovered cells? Why was Leeuwenhoek so special if someone had already observed cells before? What are the different types of microscopes we talked about. Which would be best to look at tiny projections on the surface of a bug? How are eukaryotes different from prokaryotes? Do Now Students log in at m.socrative.com or by launching their app. Do Not register for accounts. Simply enter my unique classroom number to answer questions 420161 = My Room # Objectives List the different organelles of a cell. Explain the function of each organelle. Identify each organelle in a diagram of a cell. Organelle Jigsaw Activity Do Now What are the differences between prokaryotic and eukaryotic cells? Why do we need so many more organelles than bacteria? Explain. Objectives To list and explain the different organelles found in all eukaryotic cells. To compare and contrast animal vs. plant cells. To understand which information should be studied for the quiz. Plasma Membrane The wall!- protects the internal structures of the cell. Determines what comes in and out of the cell. Cytoplasm/Cytoskeleton Cytoplasm- clear fluid that contains the organelles CytoskeletonProvides the framework for the cell, holds organelles in place. Nucleus Nucleus- controls the cell. Nucleolusproduces ribosomes. Nuclear Poresallow things in and out of nucleus. Ribosomes Makes polypeptide chains of amino acids, producing Proteins. Endoplasmic Reticulum Rough- contains ribosomes and synthesizes proteins. Smooth- No ribosomes, synthesizes lipids (fats). Golgi Apparatus Modifies proteins and fats and gets them ready for export! Vacuoles Large water “bubble” in a plant cell. Maintains the shape of the cell, without it, the plant cell would shrink and the plant would wilt. Lysosomes Contain enzymes, break down cellular waste product and debris. Centrioles Involved in cell division ( we will talk about this more later when we do mitosis!) Mitochondria Convert oxygen into energy (we will talk about this more when we do cellular respiration!) Cilia and Flagella Used in cells for movement Used in stationary cells for moving substances around the outside of the cell. Chloroplasts Capture light energy and convert it to chemical energy (sugar). Cell Wall Rigid structure Provides strength for the cell. Works with vacuole to maintain “turgor pressure” Lets brainstorm…get with a partner! What are the differences between plants and animals? http://www.youtube.com/watch?v=zafJKbMPA8 Compare and contrast plant and animal cells. Plants Animals Quiz Study Guide Organelles- what each of them do Diagrams- label both plant and animal cell. Scientists- who were they and what did they do? Cell Theory- what is it? Prokaryotes vs. Eukaryotes- what’s the difference? (the dots) Start working on your “Journey through a Cell Project” There is construction paper, colored pencils, and markers here for you to use! Do Now What is the role of the membrane in the cell? How do you think it accomplishes this role? Draw a sketch of what the plasma membrane looks like. Objectives Understand the role of the plasma membrane. Identify the components of the plasma membrane and their functions. Define diffusion. What ELSE does the membrane do? Maintains an internal environment that is different from the external environment. Regulates what molecules enter and exit the cell. Made of a phospholipid bilayer “Fluid Mosaic Model” aka the Plasma Membrane Lipids make it fluid Proteins and other components are embedded like a mosaic. http://www.youtube.com/watch?v=Qqsf _UJcfBc Phospholipid?? Gylcerol, 2 fatty acid chains, and a phosphate group “Phospho”-Hydrophillic (water loving) Polar (heads) “lipid”-Hydrophobic (water hating) Non-polar (tails) Monolayer Fatty Acids Cholesterol How blood can transport Fats in bulk! Water Bilayer Water or other hydrophilic substances Fats (hydrophobic) Water or other hydrophilic substances Selective Permeability controls the movement of substances into and out of the cell Controls AMOUNT of substances entering and leaving the cell The bilayer makes up the plasma membrane that surrounds the cell! Which of the 4 organic molecules do you see in the plasma membrane? –P.C.F.NA. Cholesterol Prevents fatty acid tails from sticking together Carbohydrates Identify chemical signals Proteins Provide channels for transport Conclusion activity Do Now- Label the different parts What is the name of the entire structure? Objectives Define diffusion. Identify the conditions that effect the rate of diffusion. Explain facilitated diffusion. Compare and contrast active and passive transport. How do things get in and out? Everybody stand up! Gather in a group by the windows, nobody is allowed behind the lab tables. Cell Membrane (transport) (Ions, Sugars, AA’s, nucleotides) (H2O, O2, CO2) T.P Large and/or ChargedTransport Protein Small and/or nonpolar molecules Diffusion RULE DiffusionMovement of molecules from High concentration to Low Concentration by random motion Me Diffusion RULE Dynamic Equilibrium-continues movement but no NET overall change Me Explain what’s happening… Perfume- Food Coloring- Initial Conditions Diffusion Low High High Low Diffusion Animations http://highered.mcgrawhill.com/sites/0072495855/student_view 0/chapter2/animation__how_diffusion_ works.html Things that Affect the speed of Passive Transport 1. Heat- Hotter the faster 2. Size- The bigger the slower 3. State of Matter Solid- Slow Liquid – Fast Gas- Fastest Passive Transport Movement of particles across the cell membrane without using energy Diffusion of Water Diffusion of Water- OSMOSIS Water can move right through the phospholipids from high to low concentration Facilitated Diffusion Movement of materials across the plasma membrane using proteins Channel Proteins Carrier Proteins Transport Proteins` Channel Proteins Pores that allow charged ions to pass through the membrane Carrier Proteins Change shape to help molecules pass through the membrane Chapter 7 Cellular Structure and Function Transport Proteins Animation http://www.stolaf.edu/people/giannini/fl ashanimat/transport/channel.swf http://www.stolaf.edu/people/giannini/fl ashanimat/transport/caryprot.swf Do Now What does “passive” transport mean? What are the different types of passive transport? What is the difference between passive and active transport? Objectives To explain active transport. To understand what happens during osmosis. To compare and contrast hypertonic, hypotonic, and isotonic solutions. Concept Map of Diffusion Active Transport Specific protein can pump molecules across the membrane Usually in opposite direction of diffusion (Low concentration to high concentration) Requires ENERGY (ATP) http://www.stolaf.edu/people/giannini/flasha nimat/transport/secondary%20active%20tran sport.swf Sodium Potassium Pump http://highered.mcgrawhill.com/sites/0072495855/student_view0/c hapter2/animation__how_the_sodium_pota ssium_pump_works.html http://www.sinauer.com/cooper/4e/animati ons1302.html Sodium Potassium Pump Type of Active Transport Moves three Na+ ions out of the cell and two K+ ions into the cell Osmosis RULE -Water always flows via osmosis from HIGH water concentration to LOW water concentration through a semi permeable membrane. Osmosis Which container has more water in it? http://www.stolaf.edu/people/giannini/flashanimat/transport/osmosis.swf Osmosis- diffusion of water across a membrane RULE -Water always flows via osmosis from HIGH water concentration to LOW water concentration -Remember SALT SUCKS- cell shrinks 22% Salt 5% Salt H2O H2 O Osmosis- diffusion of water across a membrane RULE -Water always flows via osmosis from HIGH water concentration to LOW water concentration -Cell bursts! 22% Salt 45% Salt H2O H2 O Chapter 7 Cellular Structure and Function Cellular Structure and Function Isotonic Solution Water and dissolved substances diffuse into and out of the cell at the same rate. Plant Cell Blood Cell 11,397x Hypotonic Solution Solute concentration is higher inside the cell. Water diffuses into the cell. Plant Cell Blood Cell 13,000x Hypertonic Solution Solute concentration is higher outside the cell. Water diffuses out of the cell. Plant Cell Blood Cell 13,000x 3 Types of Solutions Cell in ________ Solution Cell in ________ Solution H2 O H2 O H2 O H2 O Cell in ________ Solution H2 O H2 O For each solution, determine if the solute concentration of the solution is high, the same, or low as compared the cell. 3 Types of Solutions Plasmolysis: State where plant cells shrink in hypertonic environment (animal cells= “crenates”) Turgid: State where plant cells swell in hypotonic solution (animal cells=Lyse) Flaccid: State where a plant cell is placed in isotonic solution Cytolysis: State where cells Burst in hypotonic environment http://www.tvdsb.on.ca/westmin/science/sbi3a1/Cells/Os Osmotic Pressure Pressure builds up as water moves in and out via Osmosis In plants called Turger Pressure Worksheet Transport of Large Molecules Usually Transported by Vesicles EndocytosisInto the cell ExocytosisExiting the cell What kind of molecules do you think are usually found in the Vesicle?