Name Date Unicellular vs. Multicellular Organisms Worksheet Instructions for VIVED Science 1. Open the Plant Cell Structures and Animal (Human) Cell Structures sessions and follow the instructions. 2. Pay attention to the organelles in these plant and animal cells. Note how these cells compare to the Amoeba and Bacillus unicellular organisms. 3. Open the Human Skin session and follow the instructions. 4. Note how similar cells work together to create various tissues in the skin (an organ). 5. Open the Human Digestive model in the Human Anatomy section. 6. Note how the various organs work together to process food as part of the digestive system. 7. Open the Pig model in the Zoology section. 8. Note its various organ systems (for example, muscular, circulatory, respiratory, digestive). 9. At a research center with textbooks and the Internet, conduct in-depth research about unicellular and multicellular organisms and find the main differences in structure and function between these two types of organisms. 10. Optional: At another center, observe different types of human cells using prepared slides under a microscope (for example, skin cells, blood cells, nerve cells, muscle cells). 1
Session 1 - Plant Cell Structures 1. All living things are made up of cells, the basic unit of life. Let's take a closer look at a plant cell. 2. First, let's analyze the shape of a plant cell. Remove the adjoining plant cells to observe the center cell alone. How would you describe its shape? 3. The outside of a plant cell is covered with a thick cell wall. How would you describe it? What do you think is the function of this outer layer? Remove the cell wall to see what's underneath. 4. Directly underneath the cell wall is a cell membrane. How would you describe it? What do you think is the function of this inner layer? Remove the cell membrane. 5. Now we can see the cytoplasm, a jelly-like substance that holds the plant organelles in place. Remove the cytoplasm so that we can see the parts inside. 6. First, let's look at the nucleus. Take the nucleus apart to see what's inside it. How would you describe it? What do you think is the function of the nucleus? 7. Next, let's look at the rough and smooth endoplasmic reticulum. Lift these organelles up and look at them from all sides. How would you describe them? What do you think are their functions? 2
8. Lift up the Golgi apparatus and look at it from all sides. How would you describe it? What do you think are its functions? 9. Next, observe the central vacuole. Remove the top layer and look inside it. How would you describe it? Is it large or small? Is there one vacuole, or many? What do you think is its function? 10. Let's look at the mitochondria next. Remove the top halves of the mitochondria to see what's inside. How would you describe them? How many do you see? What do you think are their functions? 11. Finally, let's look at the chloroplasts. Remove the tops of the chloroplasts to see what's inside. How would you describe them? How many do you see? What do you think are their functions? 12. Now you know all about the organelles inside a plant cell. Conduct further research to learn about their specific functions. Bonus question: How does a plant cell compare to an animal cell? 3
Session 2 - Animal (Human) Cell Structures 1. All living things are made up of cells, the basic unit of life. Let's take a closer look at an animal (or human) cell. 2. First, notice the shape of the animal cell. Rotate the cell around and look at it from all sides. How would you describe its shape? 3. Next, use the Label tool to find out the name of the outer covering of the cell. What do you think is the purpose of this outer layer? How would you describe it? Is it thick or thin? Remove this covering and see what s inside. 4. Underneath the outer covering, we can see a jelly-like material that holds the cell's organelles. What is the name of this jelly-like substance? Remove it. 5. We now have a clear view of the organelles inside an animal cell. Take apart the nucleus to see what's inside. What do you think is the function of the nucleus? 6. Observe the rough and smooth endoplasmic reticulum. Lift these organelles up to analyze them from all sides. How would you describe them? What do you think are their functions? 4
7. Let's take a closer look at the Golgi apparatus. Lift it up and look at it from all sides. How would you describe it? What do you think is its function? 8. Now, let's observe the mitochondria. Remove the top layers of the mitochondria to see what's inside. How would you describe them? What do you think are their functions? 9. Finally, let's observe the vacuoles. Remove the tops of the vacuoles to see inside. How would you describe them? Are they large or small? How many vacuoles do you see? What do you think are their functions? 10. Now you know all about the organelles of an animal (or human) cell. Conduct further research to find out their specific functions. Bonus question: How does an animal (or human) cell compare to a plant cell? 5
Session 3 - Human Skin 1. Let's take a closer look at the parts of the human skin... 2. The epidermis is the top layer of the skin. It continually makes new skin cells that rise to the top to replace old skin cells. It also makes melanin, which gives our skin its color. Remove the epidermis layers. 3. The next layer under the epidermis is the dermis. It contains all the blood vessels, nerve endings, sweat glands, and oil glands. Now remove the dermis. 4. With the dermis removed, we can get a better look at the nerves, arteries, and veins. Pick them up and observe them more closely. 5. We can also see hairs and the sebaceous gland that produces our skin's natural oils. Pick them up to take a closer look. 6. And finally, the bottom layer of skin is called the hypodermis (or subcutaneous layer). Since this layer is mostly made of fat, it helps to keep us warm and to absorb shock. Remove the hypodermis. 7. Congratulations! Now you know about the layers of human skin. 6