Edible Cell Model - Community Science Workshop Network

Edible Cell Model Category: Biology Type: Class Experiment, 60 min class Materials: This list will provide 2 cell models, please adjust
accordingly for larger classes.
2 2 1 2 1 2 1 1 1 1 1 1 1 1 1 Large plastic cups Zippered sandwich bags Packet of Jell-­‐O Cups of clear fruit juice such as apple or lemon juice Box of gelatin Cups of boiling water Jar of cherries Box of Fruit Gushers Box of Craisins Box of Rainbow Nerds Bag of Rips Fruit by the Foot Fruit Roll-­‐Up Knife, spoon or fork Clean container or mixing bowl Video: http://youtu.be/ay-­‐VakYkVLM How To: The first step is to make the cell. For the cytoplasm, Jell-­‐O, gelatin, clear fruit juice and boiling water are needed. Place the sandwich bags in the cups as shown. The bag will represent the cell membrane. If making a plant cell model the plastic cup will represent the cell wall. © 2013 Mission Science Workshop. All Rights Reserved worldwide. When linking to or using MSW content, images, or videos, credit MUST be included. To make 2 cell cups, pour 2 cups of lemon juice into a clean container. Pour in 2 sachets of gelatin. Add half a box of Jell-­‐O to the mix. Add 2 cups of boiling water and stir until the gelatin and Jell-­‐O have dissolved. Pour the mix into the cups filling them nearly to the top. Place in the fridge until set. Remember, the Jell-­‐O mix in the bag represents an animal cell. The Jell-­‐O is the cytoplasm and the bag is the cell membrane. © 2013 Mission Science Workshop. All Rights Reserved worldwide. When linking to or using MSW content, images, or videos, credit MUST be included. The bag in the cup can represent a plant cell. For making the animal cell model, keep the bag in the cup. It makes it easier to put the different parts in the Jell-­‐O. Begin with a cherry to represent the nucleus. If the cherry has a pit, the pit will represent the nucleolus. The chery can be pushed into the Jell-­‐O using the end of the knife/fork/spoon. Fingers can also be used! Craisins represent mitochondria, and a small handful can be pushed into the Jell-­‐O. Rips represent rough endoplasmic reticulum (ER). The sugar on the Rips represents the attached ribosomes. Push into the Jell-­‐O. Tear off a piece of the Fruit Roll-­‐Up to represent the smooth ER. Push into the Jell-­‐O. © 2013 Mission Science Workshop. All Rights Reserved worldwide. When linking to or using MSW content, images, or videos, credit MUST be included. Take a small length of Fruit by the Foot and fold it as shown in the picture. This represents the Golgi Apparatus. Push into the Jell-­‐O. The gushers represent lysosomes. Push them into the Jell-­‐O. Ribosomes are represented by Nerds. Use your fingers to push them into the Jell-­‐O. Lift the bag out of the cup. The animal cell model is complete. The best part about the model is that you can eat it when you’re done! © 2013 Mission Science Workshop. All Rights Reserved worldwide. When linking to or using MSW content, images, or videos, credit MUST be included. Fine Points: The list of what is needed will depend on the size of your class. Scale up as needed! For plant cells, green Jell-­‐O can be used. To make plant cells, change the organelles and candy/fruit added. This is a very candy/sugar-­‐full model; if you want to make a healthier model, use fruits and nuts for the organelles instead. → The Jell-­‐O should be made the night before, if this isn’t possible then follow the “speed-­‐set” instructions on the Jell-­‐O box. →
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Objectives: During this lab, students will learn to: 1. Make a 3-­‐D model of a cell. 2. Identify the structures of a cell. 3. Understand the function of different cellular structures. Concepts Involved: •
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Scientists build models to help them understand how something works, what it looks like, and how the parts interact. Cells have several parts; a cell membrane, nucleus, ribosomes etc., each has a specific function. Focus Questions: 1. What do you think all the different parts of a cell do? 2. What are some ways the model we made is different from a real cell? What are some ways it is the same? 3. Why do we use cell models? Are there any disadvantages in using models? Elaboration: All living organisms on Earth are divided into pieces called cells, which are often called the building blocks of life. Organisms are defined as being either prokaryotes or eukaryotes. Prokaryotes are organisms that are made up of cells that lack a nucleus or any membrane-­‐bound organelles. Their DNA is not as organized as in eukaryotes, it is circular and “naked” within the cell. In eukaryotes the DNA is organized in to chromosomes and contained within a membrane-­‐bound nucleus. Most prokaryotes are unicellular, while eukaryotic organisms can be unicellular or multicellular. Bacteria are examples of unicellular, prokaryotic organisms; each one is a single, self-­‐contained, living cell, without a nucleus. Plants and humans are multicellular, eukaryotic organisms. Humans are made of approximately 10 trillion cells, so small that we can only see them with the help of a microscope. This number doesn’t include our gut bacteria, which number around 100 trillion! Cells contain all of the equipment that organisms need to keep them alive. All cells have a membrane, which is a structure that surrounds the cell and separates its interior from the environment outside. The membrane also controls what moves in and out of the cell. Plant and animal cells have several differences and similarities. For example, animal cells do not have a cell wall or chloroplasts but plant cells do. Plant cells have fixed, angular shapes, while animal cells come in all shapes and sizes. Let’s look at their similarities and differences: © 2013 Mission Science Workshop. All Rights Reserved worldwide. When linking to or using MSW content, images, or videos, credit MUST be included. Both plant and animal cells have special compartments in which specific metabolic activities take place. These are called “organelles”. Here’s a look at the organelles individually: Cytoplasm: Also known as the cytosol, this is the fluid that fills the cell. It contains many different molecules dissolved in water, and in it you will find proteins, fatty acids and sugars that are used to keep the cell working. Nucleus: One of the most important organelles is the nucleus. It contains sets of instructions for each cell on how to do their jobs. Different cells do different things, depending on where they are in your body. Mitochondria and Chloroplasts: These are known as the “power houses” of the cell, since they supply the cell with energy. Chloroplasts are present in plant cells. The number of mitochondria in a cell varies from one to several thousand, and depends on the organism and type of tissue. Endoplasmic Reticulum (ER): The ER has been described as a “cellular highway”, carrying cell materials wherever they need to go. There are two types of ER: the rough ER and smooth ER. The rough ER is involved in the synthesis of proteins and is also a membrane factory for the cell. It gets its name from the protein-­‐manufacturing ribosomes on its surface; these give it its "rough" looking appearance. The smooth ER doesn’t have ribosomes attached to its surface and has a different function than the rough ER. It is involved in several processes, such as the synthesis of lipids (fats), metabolism of carbohydrates and drug detoxification. Ribosomes: To perform many of their functions cells need to make proteins. The ribosomes are the protein builders of the cell. They are found in many places in the cell, including the rough ER mentioned above. Golgi Apparatus: It packages proteins inside the cell before they are sent to their destination. © 2013 Mission Science Workshop. All Rights Reserved worldwide. When linking to or using MSW content, images, or videos, credit MUST be included. Lysosomes: These are organelles that function like the “stomach” of the cell; they break down and digest the waste material. Peroxisomes: These have two important functions in the cell. They metabolize long and very long chain fatty acids, and they break down toxic materials, resulting in the formation of hydrogen peroxide (H2O2). They are able to break the hydrogen peroxide into water (H2O) and oxygen (O2), both of which are harmless to the cell. Vacuoles: These are storage bubbles that are found in cells and store food or nutrients needed for cell survival. Links to k-­‐12 CA Content Standards: Grades k-­‐8 Standard Set Investigation and Experimentation: Scientific progress is made by asking meaningful questions and conducting careful investigations. As a basis for understanding this concept and addressing the content in the other strands, students should develop their own questions and perform investigations. Grades k-­‐12 Mathematical Reasoning: 1.0 Students make decisions about how to approach problems: 1.1 Analyze problems by identifying relationships, distinguishing relevant from irrelevant information, sequencing and prioritizing information, and observing patterns. 1.2 Determine when and how to break a problem into simpler parts. 2.0 Students use strategies, skills, and concepts in finding solutions: 1.1 Use estimation to verify the reasonableness of calculated results. 1.2 2.2 Apply strategies and results from simpler problems to more complex problems. 1.3 Use a variety of methods, such as words, numbers, symbols, charts, graphs, tables, diagrams, and models, to explain mathematical reasoning. 2.5 Indicate the relative advantages of exact and approximate solutions to problems and give answers to a specified degree of accuracy. 3.0 Students move beyond a particular problem by generalizing to other situations: 3.1 Evaluate the reasonableness of the solution in the context of the original situation. 3.2 Note the method of deriving the solution and demonstrate a conceptual understanding of the derivation by solving similar problems. 3.3 Develop generalizations of the results obtained and apply them in other circumstances. Grade 5 Standard Set 1. Cell Biology Plants and animals have structures for respiration, digestion, waste disposal, and transport of materials. As a basis for understanding this concept: 2.a. Students know many multicellular organisms have specialized structures to support the transport of materials.
Grade 7 Standard Set 1. Cell Biology
All living organisms are composed of cells, from just one to many trillions, whose details usually are visible only through a microscope. As a basis for understanding this concept: 1.a. Students know cells function similarly in all living organisms. © 2013 Mission Science Workshop. All Rights Reserved worldwide. When linking to or using MSW content, images, or videos, credit MUST be included. 1.b. Students know the characteristics that distinguish plant cells from animal cells, including chloroplasts and cell walls. 1.c. Students know the nucleus is the repository for genetic information in plant and animal cells. 1.d. Students know that mitochondria liberate energy for the work that cells do and that chloroplasts capture sunlight energy for photosynthesis. 1.e. Students know cells divide to increase their numbers through a process of mitosis, which results in two daughter cells with identical sets of chromosomes. 1.f. Students know that as multicellular organisms develop, their cells differentiate. Grade 7 Standard Set 2. Genetics A typical cell of any organism contains genetic instructions that specify its traits. Those traits may be modified by environmental influences. As a basis for understanding this concept: 2.e. Students know DNA (deoxyribonucleic acid) is the genetic material of living organisms and is located in the chromosomes of each cell. Grade 7 Standard Set 2. Structure and Function in Living Systems The anatomy and physiology of plants and animals illustrate the complementary nature of structure and function. As a basis for understanding this concept: 7.a. Students know plants and animals have levels of organization for structure and function, including cells, tissues, organs, organ systems, and the whole organism. Grades 9-­‐12 Standard Set 1. Cell Biology The fundamental life processes of plants and animals depend on a variety of chemical reactions that occur in specialized areas of the organism’s cells. As a basis for understanding this concept: 1.a. Students know cells are enclosed within semipermeable membranes that regulate their interaction with their surroundings. 1.c. Students know how prokaryotic cells, eukaryotic cells (including those from plants and animals), and viruses differ in complexity and general structure. 1.e. Students know the role of the endoplasmic reticulum and Golgi apparatus in the secretion of proteins. 1.g. Students know the role of the mitochondria in making stored chemical-­‐bond energy available to cells by completing the breakdown of glucose to carbon dioxide. 1.h. Students know most macromolecules (polysaccharides, nucleic acids, proteins, lipids) in cells and organisms are synthesized from a small collection of simple precursors. 1.j. Students know how eukaryotic cells are given shape and internal organization by a cytoskeleton or cell wall or both. © 2013 Mission Science Workshop. All Rights Reserved worldwide. When linking to or using MSW content, images, or videos, credit MUST be included.