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Written Response #5 Written Response #5 • Draw and fill in the chart below about three different types of cells: Written Response #6-18 • In this true/false activity: • You and your partner will discuss the question, each of you will record your response and share your answer with the class. Be prepared to justify your answer. • You are allow to search answers. • You will be limited to 20 seconds per question. Written Response #6-18 6. The water-hating hydrophobic tails of the phospholipid bilayer face the outside of the cell membrane. 7. The cytoplasm essentially acts as a “skeleton” inside the cell. 8. Plant cells have special structures that are not found in animal cells, including a cell wall, a large central vacuole, and plastids. 9. Centrioles help organize chromosomes before cell division. 10. Ribosomes can be found attached to the endoplasmic reticulum. Written Response #6-18 11. ATP is made in the mitochondria. 12. Many of the biochemical reactions of the cell occur in the cytoplasm. 13. Animal cells have chloroplasts, organelles that capture light energy from the sun and use it to make food. 14. Small hydrophobic molecules can easily pass through the plasma membrane. 15. In cell-level organization, cells are not specialized for different functions. Written Response #6-18 16. Mitochondria contains its own DNA. 17. The plasma membrane is a single phospholipid layer that supports and protects a cell and controls what enters and leaves it. 18. The cytoskeleton is made from thread-like filaments and tubules. 3.2 HW 1. Describe the composition of the plasma membrane. 2. List functions of the cytoplasm and cytoskeleton. 3. What is the role of the nucleus of a eukaryotic cell? 4. List three structures that are found in plant cells but not in animal cells. 5. Outline the levels of organization of cells in living things, starting with the simplest level, that of single-celled organisms. 6. Create a diagram to show how the cells of multicellular organisms may be organized at different levels, from the level of the cell to the level of the organ system. Give an example of a multicellular organism at each level of organization. 7. Explain why hydrophobic (“water-hating”) molecules can easily cross the plasma membrane, while hydrophilic (“water-loving”) molecules cannot. 8. What is endosymbiotic theory? How does it explain the presence of certain organelles in eukaryotic cells? 9. Explain how the following organelles ensure that a cell has the proteins it needs: nucleus, rough and smooth ER, vesicles, and Golgi apparatus. What Do Cells Share? • Structures found in all cells: • DNA organized as chromosome(s). DNA directs cell activity What Do Cells Share? • Structures found in all cells: • Cytoplasm is the “filling” of the cell and is made up of 90% water. Water provides the necessary environment for all the chemical reactions the cell needs. What Do Cells Share? • Structures found in all cells: • Ribosomes are organelles that are the site of protein synthesis. Proteins are essential for enzymes, structure and communication. What Do Cells Share? • Structures found in all cells: • Cell membrane (plasma membrane) • Composed of a phospholipid bilayer with embedded proteins. The fluid mosaic model describes the structure of the cell membrane. • Fluid: individual phospholipids and proteins can move past each other; they are not fixed in one position. • Mosaic: the membrane has more than one type of molecule (phospholipids and proteins). • Functions of the cell membrane: • Selectively permeable: regulates what enters and leaves the cell. This helps maintain homeostasis. • Gives the cell (cytoplasm) shape. Cell Membrane Reading - Handout Cell Membrane Structure - Both • Composed of a phospholipid bilayer with embedded proteins. • Fluid mosaic model describes the structure of the cell membrane: • Fluid – Individual phospholipids and proteins can move past each other; they are not fixed in one position. • Mosaic – The membrane has more than one type of molecule (phospholipids and proteins) Cell Membrane Function - Both • Selectively permeable: regulates what enters and leaves the cell. • This helps maintain homeostasis. • Gives the cell (cytoplasm) shape. • Explain why hydrophobic (“water-hating”) molecules can easily cross the plasma membrane, while hydrophilic (“water-loving”) molecules cannot. Written Response #19 • Thoroughly answer the question below. Use appropriate academic vocabulary and clear and complete sentences. • Discuss the properties of the plasma membrane that allow it to act as a barrier around the cell. Include the specifics of the phospholipid bilayer. Cell Wall – Plants Only Provides extra support, protection, and shape for the cell. Found outside the cell membrane Made of cellulose Cytoplasm - Both • The “filling” of the cell and is made of up to 90% water. • Water provides the necessary environment for all the chemical reactions the cell needs. Cytoskeleton - Both • Made of microtubules and microfilaments that provide structure and shape for the cell. Nucleus - Both • Surrounds the chromosome for additional protection. • Made of a phospholipid bilayer. • What are the benefits of the nucleus being made up of a phospholipid bilayer? Vacuoles - Both • Store food, waste or water to be used inside the cell or excreted from the cell. • Vacuoles are larger in plants than animal cells. Centrioles – Animal Only • Organelle that helps with cell division. • Found only in animal cells. Lysosomes - Both • Contain digestive enzymes which digest food contained in vacuoles as well as old or damaged parts. Chloroplast – Plants Only • Organelles full of chlorophyll that are the site of photosynthesis which produces sugars. (C₆H₁₂O₆) • Thylakoid responds to solar radiation to produce sugar. • Composed of folded membranes for more surface area. Golgi Apparatus - Both • Packages materials for export from cells. • Cellular “Post Office” Mitochondria - Both • Site of cellular respiration which produces cell energy (ATP). • Structure contains folded membranes which increases surface area allowing more space for reactions. Smooth Endoplasmic Reticulum “Smooth ER” - Both • Extension of the nuclear envelope. • Plays important role in cellular maintenance of lipids. Rough Endoplasmic Reticulum Rough ER - Both • “Rough” because of the ribosomes attached to the membrane. • Aids in protein production. Ribosomes - Both • Organelles that are the site of protein synthesis. • Proteins are essential for enzymes, structure, and communication. • Which enzymes are in charge of communication? Written Response #20 • Explain how the following organelles ensure that a cell has the proteins it needs: nucleus, rough and smooth ER, vesicles, and Golgi apparatus. Nucleolus - Both • A dense region located in the nucleus. • Manufactures ribosomes. DNA - Both • Directs cell activity. • Organized as chromosomes. • Double helix in shape. Chromosomes - Both • Tightly packed coils of DNA and proteins that form during cell division. (Mitosis) • Human have 46. Cilia/Flagella - Both • External cell organelles that aid in movement. • Flagella are long and whip like. • Cilia are short and hair like. Written Response #21 – Cellular Adaptations • Single celled organisms rely Adaptations Description heavily on adaptations to Pseudopod carry out life processes. • Once you and your table Cilia / Flagella partner have completed your charts, raise your hand so that Eyespots I may check you off for completion. Pili • Once you have been checked Contractile off, you and your partner will create a poster to represent vacuoles the cellular adaptations. • Be sure to include a drawing Increased as well as how these mitochondria adaptations have increased the survival of single-celled organisms. Chemotaxis / Phototaxis Written Response #22 • What is endosymbiotic theory? How does it explain the presence of certain organelles in eukaryotic cells? Cell Compare - Handout • Complete the handout with your table partner. Once finished, raise your hand so I can come check you off for completion. • Once you have been checked off, glue/tape the handout into your notebook. peroxisome mitochondrion smooth ER DNA vacuole nucleolus nucleus rough ER chloroplast cell wall golgi apparatus cell membrane ribosome Plant Cell Art - Handout • Complete the handout by completing the function of the organelles and coloring the appropriate color. • Raise your hand when you have completed the handout and I will come check you off for completion. • Once you have been checked off for completion, glue/tape the handout into your notebook. peroxisome smooth ER vacuole nucleolus DNA lysosome nucleus mitochondrion rough ER golgi apparatus cell membrane centriole ribosome Animal Cell Art - Handout • Complete the handout by completing the function of the organelles and coloring the appropriate color. • Raise your hand when you have completed the handout and I will come check you off for completion. • Once you have been checked off for completion, glue/tape the handout into your notebook. Wanted Ad: Cell Structures and Organelles • Design 3 wanted posters for 3 different cell structures or organelles. • On the wanted poster, you must tell: • Who you are (what type of cell) • Why you need the organelle or structure. • A way of contacting you (make it up) • A reward for obtaining the organelle or structure (make it up) • You must also include a picture of the cell you are representing and the organelle or structure you are seeking. Edible Cell - Activity Organelle Type of Description (why Candy did you use this • You and your lab group candy) will decide on a cell type and select 12 organelles 1. that will be represented 2. by different types of 3. candy. 4. • Draw and complete the 5. chart as you are making your cell in your 6. notebook. 7. • I must check you off prior 8. to eating any part of your 9. cell. 10. 11. 12..
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