Pre-lab homework Lab 4: The Cell Lab Section: Name: After reading over the lab and chapter 5 in your textbook, answer these questions to be turned in at the beginning of the lab! 1. Define organelle 2. What is the difference between a prokaryotic cell and a eukaryotic cell? 3. In which kingdoms will you find organisms composed of prokaryotic cells? 4. In which kingdoms will you find organisms composed of eukaryotic cells? 5. Which organelle(s) are found only in plant-like eukaryotic cells? 6. Which organelle(s) are found only in animal-like eukaryotic cells? Hint: If you want to get a jump on this lab feel free to complete the tables on pages 4 and 5 prior to coming to lab. Your textbook will help you with this! 1
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Name Lab 4 - The Cell Cells are referred to as the basic structural and functional units of living things. Even though cells are extremely small, we can look inside for even smaller structural components. There are two basic cell types found in living organisms. Prokaryotic cells are found in members of the domains Bacteria and Archaea. When we look inside these cells we do not see smaller membrane bound structures. These cells work just fine but their organization is very simple. Eukaryotic cells are found in members of the domain Eukarya. Which Kingdoms are found in this Domain? Eukaryotic cells are composed of smaller membrane bound structures called organelles. Each organelle has a specific function for the cell. Within Eukarya there are two cell subtypes: plant-like cells and animal-like cells. These subtypes share most of the organelles but there are a few differences between them. Within the domain Eukarya the Kingdom Animalia has animal-like cells. Which other kingdom(s) have animal-like cells? Within the domain Eukarya the kingdom Plante has plant-like cells. Which other kingdom(s) have plant-like cells? Below is a list of organelles found in eukaryotic cells. Complete the table by drawing a sketch of the organelle (make it good enough that you can tell the organelles apart!) and stating its function. Also note whether this organelle is found in plant-like cells, animallike cells or both. 3
ORGANELLE SKETCH FUNCTION PLANT OR ANIMAL CELL? cell wall plasma membrane rough endoplasmic reticulum smooth endoplasmic reticulum ribosome golgi apparatus (complex) lysosomes nucleus 4
ORGANELLE SKETCH FUNCTION PLANT OR ANIMAL CELL? nucleolus mitochondria chloroplast vacuole cilia flagella cytoskeleton centriole 5
Now you will be working with a partner to create a model of a specific eukaryotic cell. Who are you working with? You and your partner have been assigned a cell from which to create a model. What is the name of the organism? Is the cell you are modeling an animal-like cell or a plant-like cell? Focus your cell on the microscope. You will want a total magnification of 400X. Which organelles from your list can you see using your microscope? Now you are ready to create a model. Start with only the organelles you can see in the microscope. You will create your model on the tray provided and use play-doh to make the organelles. Be sure that each organelle you add to your cell looks different from the other organelles (they should not all look like little round blobs). Once you have completed this part of the model have your instructor check it. Be sure you can explain to your instructor which organelles you have included and what they do! INSTRUCTOR INITIALS: 6
Were you surprised by the number of organelles you could see at 400X? Most of the organelles are so small we cannot see them with a light microscope (like yours!). In order to see most organelles we would need an electron microscope that can magnify more than a hundred thousand times! Now pretend you are looking through an electron microscope and add to your model all the other organelles you find in the type of cell you have. You now have a complete model of either an animal-like cell or a plant-like cell. Find a group that has completed a model of the type of cell you did not do (if you did an animallike cell find a group that did a plant-like cell or visa versa). Who are the people in this group? Compare your models. Whichever group created an animal-like cell should point out the organelles unique to animal-like cells. Whichever group created a plant-like cell should point out the organelles unique to plant-like cells. Which organelle(s) are found only in the plant-like cell? Which organelle(s) are found only in the animal-like cell? Some organisms are composed of a single cell (unicellular) while other organisms are composed of many cells (multicellular). Humans are an example of a multicellular organism. In humans you will find muscle cells, nerve cells, skin cells, gland cells, blood cells etc. All of these cells are animal-like (since humans are in the kingdom Animalia!) but they will look different because of their unique jobs in the body. 7
Several microscopes have been set up with different types of human cells. Look at each type of cell and sketch the shape of the cell. How do you think the shape relates to the function of the cell? Cell Type (name on slide) Sketch Why do you think this cell has this shape? 8