EcosystemsThe Big Ideas
Essential QuestionsCarbon Snakes
- In ecosystems, living and non-living things interact in complex ways.
- Because of these interactions, energy flows and matter cycles through ecosystems.
Set your notebook page up for Cornell NotesFocus Question: What is inside sugar?Main Idea: When we add sulfuric acid to sugar, it will break the sugar molecules apart. Make careful observations to determine what sugar is made of. If you were absent from class, you can watch this video instead.
- How does energy move through ecosystems?
- How does matter move through ecosystems?
Notes:In your notebook, write down 10 observations from the experiment. Be sure to include as much detail as possible.Summary:Answer the question. What is inside sugar? Explain your evidence.Cell ExplorerGo to the Exploratorium's "Cell Explorer." Then click on the first section, "Where do you get your energy?" Read and watch the animations carefully. You can go forward and backwards to make sure you understand well. As you read, fill in the blanks in the notes. Then use your notes to help you do the Dragster activity. Keep trying until you get 100%.Rearranging AtomsHow do energy and matter move around an ecosystem? First, what is matter? (Not "what's that matter" What IS matter?) Matter is the stuff that makes up the world around you. The stuff that takes up space. Solids, liquids, and gasses all take up space. I know it doesn't feel like the air takes up space, but it does! You can fill a balloon with air, so it takes up space inside the balloon. Light exists, but it doesn't take up space. No matter how brightly you shine your flashlight into a balloon, it will never fill up. That's because light is not matter, it's energy. Heat and electricity are also familiar forms of energy. Both matter and energy can move through ecosystems.Ecosystems can be really big, and energy and matter move around those large systems, but this movement actually begins very small. How small? As small as a molecule. So how small is a molecule? To see, visit the Cell Size and Scale interactive display from the University of Utah Genetics Department, and slowly adjust the slider until you see the glucose molecule. Energy flow in ecosystems begins with that tiny little molecule. It stores energy, and cells release that energy when they break it down. Find out how matter moves at the same time by completing the Rearanging Atoms slides activity.To do this activity with beads instead of electrons, follow these directions."Planet Earth: From Pole to Pole"Just like other systems, Ecosystems are made of parts that interact with each other. In ecosystems, some of the parts are living and some are non-living. The non-living factors have a dramatic effect on which living things can survive in an environment. While you watch the documentary, "Planet Earth: From Pole to Pole," watch for two important non-living factors: the temperature and the amount of water in an environment. As the video takes you from one environment, think: "How much rainfall water is in this environment? What is the temperature like? How many kinds of living things live here?"We also want to pay attention to relationships between organisms in these ecosystems. You guys all know about predator-prey relationships, but there are so many more! Can you find examples of competition? mutualism? commensalism? parasitism?
Plant vs. Animal Cells
Can you think of characteristics that plants and animals share? What are some ways that they are different? Those similarities and differences actually start at the cellular level. Plant and animal cells have certain features in common and each have unique features as well.
Use the University of Utah's "Inside a Cell" activity to compare plant and animal cells. In your notebook, create a venn diagram with "plant cells" on one circle and "animal cells" on the other circle. In the Venn diagram, list the organelles that are found in each type of cell.
Plant Cell Scale ModelThe movement of energy and matter in entire ecosystems begins with microscopic organelles of microscopic cells. The chloroplasts in plant cells capture the sun's energy and make food for all organisms in the ecosystem. Tiny mitochondria in plant and animal cells break down glucose, providing energy for plants to grow, mushrooms to reproduce, and flocks of birds to migrate in summer.If we want to understand an ecosystem, then, we have to understand even it's tiniest parts: organelles. Since they are so important, we're going to review them by constructing a scale model of a plant cell. Use the directions on the front and back of the project sheet to make your model.
- Click on "Make Cell Membrane Transparent." Then you will be able to see inside the cell.
- To see the name of an organelle in the animal cell, mouse over it. For more detail, click on it.
- Change the cell to a plant cell. Do you still see that organelle? If so, then it is in both kinds of cells, and you should put it in the middle of your Venn diagram.
- Repeat these steps for the other organelles, and complete the Venn diagram as you work.
Elodea CellsWe've looked at model plant cells; now let's look at some real plant cells under the microscope! To learn how, watch this Zaption video.Lettuce LabIf you put lettuce in water and put it in a sunny place, bubbles will form on the lettuce and the inside of the jar. An internet site says that the bubbles are oxygen produced when the lettuce does photosynthesis, but are they really? Let’s experiment to find out! If you were absent, you may get the data from your group. You must write your own hypothesis and conclusion, though.Bill Nye Food WebsOne of our essential questions asks "How does flow move through an ecosystem?" Watch the Bill Nye Episode on Food Webs to find out. Take Cornell notes in your science notebook. For the summary, answer the essential question based on what you learned in the video.Spin a Food WebEnergy enters most ecosystems through photosynthesis, when plants and other producers capture the sun's energy and store it in food molecules. Then what happens to the stored energy? Some is used by the producer, but some gets passed on through the food web. Complete the Dragster activity to find out!
- You may make it 2-D or 3-D, but each part must be built or cut out (with the exception of the ribosomes).
- The mitochondria must be red.
- The chloroplasts must be green.
- All other colors are up to you, but each cell part should be a different color.
- The cell wall and cell membrane go around the entire cell, so you should make them as long as the entire cell.
- Use glue to connect your cell wall outside your cell membrane.
- Extra credit will be given for creative ways of building your model IF the basic requirements are met (especially using the correct scale).
Organic Molecules Image Quest
What's the matter with you? Uhm ... I mean ... What's the matter IN you? Like all living things, you are made of cells, and your cells are made of molecules, and molecules are made up of smaller parts called atoms. Living things are made of special molecules called organic molecules. Let' learn more about what you're made of:Atoms are like magical Legos. Just like legos, the same pieces can be combined in many different ways to make very different things. With Legos, though, the major difference is the shape of the things you make. With the same legos, you can make a house, a T-rex, or a spaceship. With atoms, you can make different molecules that also have different shapes, and when molecules are shaped differently, they can have very different characteristics. Combined in different ways, the same elements (atoms) that make up olive oil make up bacon grease, sugar, and fiber!What elements make up these different organic molecules? Click on the links below, and examine the images to find out. Set up Cornell notes in your science notebook and take notes as you go. The focus question is: "What are the primary elements that make up organic molecules?" List the name of each molecule you examine. Next to the name, list the elements you find in the molecule. Use the periodic table to find out the names of the elements you see in the molecular models.
Lipids are fats and oils, like bacon grease or canola oil, or your own belly fat. These molecules store a lot of energy. Hormones like adrenaline and estrogen are also lipid-based. All of your cells are surrounded by lipids too because the cell membrane is mostly made of lipids.
Proteins are large organic molecules made up of smaller molecules called amino acids (Note: The R is not an element, it stands for an "R Group," which is a chain of hydrogen and carbon). Your muscles have a lot of protein. That's why body builders will often drink protein shakes when they work out to help build muscle. Every cell in your body has proteins too, though. Your cell membrane have proteins that help transport materials into and out of your cells. You also have special proteins called enzymes that are important for chemical reactions like copying DNA as well as doing cellular respiration.
Carbohydrates include sugar, starch, and fiber. Sugars, like glucose, and starches are mostly used for storing energy. Plant cell walls are mostly made of cellulose, which is also a carbohydrate.
- DNA / RNA
Nucleic acids are made up of nucleotides. As you know, these store the genetic information that our cells use to make proteins.
When you’re done examining the molecules and taking notes, write your conclusion based on your observations: What are the primary elements that make up organic molecules?Nitrogen CycleWe learned from Bill Nye that energy gets used up as it moves through the food web. It's not really gone, it just isn't useful any more. Just like if you keep sharpening your pencil and writing, the pencil doesn't really go away. It's still there: the lead is on your paper where you wrote, and the pencil shavings are in the sharpener. The pencil just isn't any good for writing after that. Matter is different, though. Matter stays around and gets recycled in the ecosystem.Remember our "Rearranging Atoms" activity? When you took apart the glucose molecule, the atoms didn't disappear, you put them together to make new molecules. That's what happens in the ecosystem. Unlike energy, matter just gets taken apart and put back together again in new ways. The carbon that's in your molecules came from the carbon in your food. So where do you think you get the nitrogen you need to make protein molecules?The carbon, nitrogen, oxygen, and all the other elements our bodies need get cycled around the ecosystem. Let's take a look at one of these cycles, the nitrogen cycle. Before you start, draw these three molecules in color at the top of the page: nitrogen gas, ammonia, ammonium, and nitrate. Then watch the BrainPop video called the Nitrogen Cycle. Take notes in your science notebook on the top half of your page. Save the bottom for the second part.When you're done, draw your own nitrogen cycle on the bottom half of your page. Your cycle must show these parts: soil, atmosphere, bacteria, plants, animals, and waste.Use all of your notes from the ecosystems unit to answer the essential questions. Give complete, detailed answers. Use all the key words listed for each question in a way that shows that you know what it means and how it helps answer the question.
We're dissecting owl pellets! What's an owl pellet? It's the parts of an owl's meal that it can't digest. The owl swallows its prey whole; then the owl's gizzard separates the part of the prey that it can digest from the fur, bones, and any other parts that it can't digest. The owl then regurgitates the indigestible parts.Why dissect something so gross? It will show us how we can study an organism's habitat and its role in the habitat without even seeing the organism itself. It will also be a good review of bones and anatomy, which will help us get ready for our evolution unit! Three lessons in one!Your job is to dissect an owl pellet and determine what the owl ate in that meal. Did it eat a rodent? Did it eat two rodents? Did it eat a bird or insects? After you dissect it, you will assemble the skeleton or skeletons on a sheet of construction paper. This is the data you will use to answer the questions.Before you begin the actual dissection, you need to do the virtual dissection. This was to help us learn the shapes and names of the bones as well as how they fit together. In your real owl pellet, the skeletons may be incomplete, there may be more than one skeleton, and bones can be broken. The virtual dissection is much more straight-forward. Your owl pellet will contain one, complete skeleton that you can assemble. When you are done with the virtual dissection, do the Owl Pellet Bone Identification QuizStar to prove that you really learned it. You must get 100% on the QuizStar to begin the dissection. It's not a quiz, though, so be sure to ask for help if you get stuck! The purpose is to learn. Here are some tips for the virtual dissection and QuizStar.
- How does energy move through ecosystems? (Be sure to include how energy enters the ecosystem and what happens to it as it moves up the food pyramid.)
photosynthesis, food web, food pyramid, energy, sun
- How does matter move through ecosystems?
atoms (carbon, nitrogen, hydrogen, oxygen), molecules (protein, carbohydrates, lipids, DNA), food web, photosynthesis
- Place all the LARGE bones on the skeleton.
- DON'T put all the vertebrae on the skeleton.
In fact, only put one or two vertebrae in each part (cervical, thoracic, lumbar, and caudal). If you put them all together,there will be 3 problems: 1-The bones will animate and disappear, so you won't be able to look back at them while you do your QuizStar. 2-It will take a long time. Remember, your grade is based on the QuizStar, not the virtual dissection, and 3-You won't be able to see the shape of the individual vertebrae (They are different in each part of the spine. On your QuizStar, you will need to know the shape of the different types of vertebrae).
- It is hard to tell the difference between the pelvic bone and the tibia-fibula. Although they both have holes in one end, the shape is different. The end of the tibia-fibula looks a little like a bow for a bow and arrow. The tibia is thick and bows outward, the fibula is thin and straight like the string of the bow. The end of the pelvic bone, on the other hand, has a triangle shape and no skinny, straight part.
- The pelvic bone connects the leg to the spine, it is NOT part of the leg. The femur is the upper part of the hind limb.
- The rodent's forelimbs are the legs that are closest to the head. They come beFORE the other legs. Its hind limbs are the legs that are beHIND the forelimbs.