Name: Cellular Structure and Function Unit 3; Chapter 7 Date Classwork Homework Notes: History of Cells Read/Questions Chapter 7.1 and 7.2 Venn Diagram Origins of Eukaryotic Cells Notes: Membranes Membrane Lab Notes: Organelles Cell Flip Book, Day 1 Cell Flip Book, Day 2 Cell Lab Comparing Plant and Animal Cells Cell City Analogy Review Sheet Notes: Transport Gummi Bear Lab, Day 1 Gummi Bear Lab, Day 2 Notes: Transport (finish) Osmotic Solutions Worksheet Gummi Bear Lab, Day 3 Endocytosis Lab Work on Potato Lab Finish Potato lab Test Review Test Finish Origins Reading/Questions Read/Questions Chapter 7.3 Color/label Cell Diagrams Finish Cell Flip Book Finish Cell Lab Finish Review Sheet (page 31) Read/Questions 7.4 Finish Osmotic Solutions Worksheet Finish lab questions Study for Test Finish Lab questions Complete packet and study Prepare for next unit Rubric: Out of Reading Questions 40 PowerPoint Notes 20 Venn Diagram 10 Origins of 10 Eukaryotic Cells Membrane Lab 20 Flip Book TBA Comparing Lab 20 Osmotic Solutions 10 Gummy Bear Lab 20 Endocytosis Lab 10 Potato Lab 20 Total Your Score
7.1 Before You Read: Reading Questions 7.3 Before You Read: 1. 1. 2. 2. 3. 3. 4. 4. 5. 5. 7.2 Before You Read: 6. 7. 1. 2. 7.4 Before You Read: 3. 4. 5. 1. 2. 3. 4.
What did Robert Hooke call the boxes that he observed in cork? Why should I care? So, what is a cell? Smallest that can support life A bacterium is selfsustaining cell You are made up of trillions of cells Too small to see without a microscope 3
Problem? Miss Apgar wants to view a bacterial cell that needs to be magnified 1000 times in order to see it. Her compound light microscope has a 10X ocular lens. Which objective lens should she use to see the bacterium? Where is the ocular lens? Where is the objective lens? What do we remember about microscope history? Robert Hooke Named the cell Cell Structural and functional unit of life Made sketches of the microscopic world Anton van Leeuwenhoek Perfected a single lens microscope Examined and Called creatures he saw cavorting wee beasties 4
Some More History Matthias Schleiden Studied plants Determined that all Theodor Schwann Studied animals Determined that all Some More History Rudolf Virchow German physician Proposed that cells to form new cells Used his theory to diagnose patients Father of pathology Cell Theory - putting their work together All organisms are made of cells The cell is the basic unit of organization in living organisms All cells come from pre-existing cells 5
How do we know that cells come from other cells? Two types of cells Prokaryotic cells Simple interior Considered to be the Eukaryotic cells Complex interior Considered to be the 6
Prokaryotes Simple interior DNA in central region Cellular happen in open space Single cell organisms Bacteria Archaea Inside a Prokaryote The is where cell life takes place DNA is concentrated in the nucleoid region Ribosomes make proteins The Flagellum provides Capsule, cell wall, and cytoplasmic membrane provide Eukaryotes Complex interior DNA is neatly packaged and protected by perform cellular functions Single and multiple cell organisms Amoebas single celled 7
4 Kingdoms Animalia Ex: Plantae Ex: Fungi Ex: Protista Ex: Inside a Eukaryote The is where the organelles are located DNA is housed in the Ribosomes make proteins There are many other organelles each covered by a Each organelle has its own function provides protection 8
More on the Eukaryote cell Important terminology DNA Organelle that carry out Means little organ First up: the plasma membrane The Cell Membrane The cell membrane is selectively permeable Cell membranes are made from a 9
Phospholipid Bilayer Structure Each phospholipid has a head and two tails Polar head is attracted to water Nonpolar tails are repelled by water Outside of cell Cell membrane Proteins Carbohydrate chains Inside of cell (cytoplasm) Protein channel Lipid bilayer Phospholipid Bilayer Function Allows some things in and not others Polar molecules do not pass H 2 O is an exception because it is small Keeps the outside and the inside The plasma membrane is always in motion Fluid Fluid Mosaic Model Membrane is _ Membrane is _ Mosaic There are molecules in the bilayer The looks like a mosaic 10
Animal Cells vs. Plant Cells Eukaryotic cell which makes up tissues in animals Lack and, and have smaller vacuoles. Appears to be because of the lack of a rigid cell wall. Eukaryotic cell that makes up plants Animal Cell 11
Plant Cell Cell Wall Mesh of that surrounds the Protects and supports the cell Made of carbohydrate - Cytoplasm Semi-fluid material inside the plasma membrane Consists of and the cellular organelles (all organelles except the ) Cytosol - 12
Cytoskeleton Network of long, thin protein fibers provide an for organelles - long hollow cylinders that assist in within the cell - thin threads that give the cell shape and enable the cell to Nucleus Contains genetic material (DNA) Nuclear envelope Nuclear pores allow in center Very dense center Ribosomes Produce Made of RNA and protein Made in the Some in the cytoplasm Others to endoplasmic reticulum 13
Endoplasmic Reticulum Interconnected network of tubules Two types of Endoplasmic Reticulum Rough ER Smooth ER Where No ribosomes Produces complex attach and make proteins Appear to create bumps and and rough areas on the membrane Golgi Apparatus Modifies, sorts, and packs proteins in sacs called Vesicles fuse with plasma membrane They release proteins which move through membrane to get outside of the cell 14
Vacuoles storage for materials in the cytoplasm Store, transport, or digest food and waste Plant cells 1 large vacuole Animal cells several little vacuoles Lysosomes Vesicles that contain to digest excess or worn-out organelles and food particles They also digest bacteria and viruses that enter the cell They are in the Golgi apparatus. Centrioles Made of Microtubules Found near nucleus only Assembled right before replication Aid in cell 15
Mitochondria Powerhouse Converts organic materials into ATP Outer and inner membranes with lots of folds Provides large surface area to break (produce energy) Chloroplasts- Plant only Capture and convert it to through photosynthesis Photosynthetic Animals 2010 - found an animal that makes proteins essential for photosynthesis Elysia chlorotica sea slug that looks like a giant swimming leaf Stole from algae it eats can live up to 9 months without eating Appears because of stolen chlorophyll Lives - Eastern coast of the United States and Canada 16
Cilia and Flagella Cilia-, hair-like projections Move back and forth like oars on a rowboat Move substances along surface of the cell Flagella- rather hair-like projections Whip-like motion Both are composed of microtubules cells through watery environment 17
Cell Transport Passive Transport Does not use energy Goes the concentration gradient 3 types diffusion facilitated diffusion osmosis Active Transport Goes the concentration gradient Endocytosis Exocytosis Cell Transport Diffusion -net movement of particles from concentration to concentration Doesn t require energy because the particle are in motion passive transport Dynamic equilibrium- the overall concentration does not change, but molecules are still What affects the rate of diffusion? What makes molecules move faster? High High High 18
Facilitated Diffusion Some ions and molecules can t across the cell membrane Facilitated diffusion uses to help move some molecules across the plasma membrane Osmosis Osmosis diffusion of Most cells undergo osmosis because they are surrounded by water Hyper Hypo Iso tonic Solutions These are comparing words Hypertonic -_ Hypotonic- Isotonic- What would happen if you Put a red blood cell in a hypertonic solution? Put a red blood cell in a hypotonic solution? Put a red blood cell in an isotonic solution? 19
What happens to a red blood cell when? Active Transport Goes from to concentration Requires Energy ATP Moves Endocytosis Endocytosis- moving large substances into the cell 20
Exocytosis Exocytosis- moving large substances out of the cell 21
Comparing Prokaryotic and Eukaryotic Cells Prokaryotic Cells Eukaryotic Cells 22
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Reading Questions: 1. Who proposed the endosymbiont hypothesis? 2. Billions of years ago chloroplasts and mitochondria were. 3. What is symbiosis? Give a detailed description. 4. What does the prefix endo- mean? 5. Explain what an endosymbiont is. 6. What is a common example of an endosymbiont? 7. Explain in detail the beneficial relationship between hydra and algae. (Must be 3 or more sentences) 25
8. What evidence suggests that algae are beneficial to the hydra? 9. How do the mollusks harvest the energy from the algae? 10. What is the benefit to the mollusk with the algae compared to mollusks without algae? 11. What happens when the chloroplasts in the mollusk stop functioning? 12. How does this relate to the endosymbiont theory? When you are finished work on your homework reading and questions 26
Problem: Is the cell membrane a selective barrier? Hypothesis: Cell Membrane Lab Materials: Microscope Microscope slides and cover slips Yeast Methylene blue stain (Be careful!!) Water Heated water Eye droppers/pipettes 2-500mL beakers Stirring rods Procedure: 1. Done for you: Place a packet of dry active yeast in a beaker. Add 400mL of water and stir. a. One per class. 2. Done for you: Boil 400mL of water and one packet of yeast for 10 minutes and let cool. a. One per class. 3. Prepare a slide of the yeast in the warm water: a. Place a drop of the solution on a clean slide. b. Place a drop of Methylene blue onto the drop of yeast solution. c. Carefully cover it with your cover slip, remembering to drop it at an angle. 4. Look at the slide under the microscope, remembering to start focusing with low power first. 5. Find a good example of the yeast under high power and draw what you see in the data section below. 6. Repeat steps 3-5 for the yeast that has been boiled. Data: x Yeast Cells in Warm Water Boiled Yeast Water Mixture x Conclusion: 1. Explain how boiling affected the yeast cells. 2. Why does the color of the two groups of cells differ? (remember to consider the role of the plasma membrane) 3. Are the plasma membranes selective barriers? Explain your answer. 27
Cell Flip Book Assignment Your task is to create a cell flip book that you can use to study for this chapter. This is an INDIVIDUAL assignment. You must include all of the organelles listed below and the following for each organelle: Colored hand drawing Organelle function Where it is found (Prokaryotes: Bacteria and Archaea, Eukaryotes: Plantae, Animalia, Fungi, and Protista) Organelles: 1. Cell Membrane 2. Cell Wall 3. Nucleus 4. Nucleolus 5. Cytoplasm 6. Ribosome 7. Smooth Endoplasmic Reticulum 8. Rough Endoplasmic Reticulum 9. Golgi body 10. Chloroplast 11. Mitochondria 12. Centriole 13. Lysosome 14. Peroxisome 15. Vacuole 16. Cilia/Flagella Rubric Organelle Cell Membrane Cell Wall Nucleus Nucleolus Cytoplasm Ribosome SER RER Golgi Body Chloroplast Mitochondria Centriole Lysosome Peroxisome Vacuole Cilia/flagella Drawing Function Where Found Good (1) Poor (0) Good (1) Poor (0) All (1) Missing (0) Total Points: (out of 48) 28
Color and Label the Plant Cell 29
Color and Label the Animal Cell 30
Color and Label the Bacteria (Prokaryotic) Cell 31
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Lab Comparing Plant and Animal Cells Objective In this investigation, you will compare the structure of a typical plant cell (elodea) and a typical animal cell (human). Materials: Elodea leaf Microscope slide Toothpick Compound Light Microscope Methylene blue (be careful!!) Procedure Part A: Examining Plant Cells 1. Place a drop of water in the center of a clean microscope slide. 2. Remove a leaf from the elodea plant and place it on the drop of water on the slide a. Make sure the leaf is flat, if it is folded unfold it 3. Carefully place a coverslip over the elodea 4. LOW POWER- locate the leaf 5. Switch to medium or high power objective lens. 6. Observe the cells of the Elodea leaf. Draw and label what you see x Part B: Examining Animal Cells 1. Place a drop of methylene blue on your slide a. The less the better. 2. Gently rub a clean toothpick along the inside of your cheek. 3. Rub the same toothpick on the methylene blue. 4. Carefully place a coverslip over the cheek cells 5. LOW POWER- locate the cells 6. Switch to medium or high power objective lens. 7. Observe the cells of the cheek cell. Draw and label what you see x 34
Observations 1. What is the shape of an elodea cell? 2. What is the general location of the nucleus in an elodea cell? 3. What is the shape of a human skin cell? 4. What is the general location of the nucleus in a human skin cell? 5. How are plant and animal cells similar in structure? 6. How are plant and animal cells different in structure? 7. Explain why you cannot use an oak leaf in this investigation? 8. In general, the surface of a tree has a harder feel than the surface of a dog. What characteristics of each organism can be used to explain the difference? 9. If you were given a slide containing cells of an unknown organism, how would you identify the cells as either plant or animal? 35
Cell City Analogy In a faraway city called Grant City, the main export and production product is the steel widget. Everyone in the town has something to do with the steel widget making and the entire town is designed to build and export widgets. The town hall has the instructions for widget making; widgets come in all shapes and sizes and any citizen of Grant can get the instructions and begin making their own widgets. Widgets are generally produced in small shops around the city; theses small shops can be built by the carpenters union (whose headquarters are in the town hall). After the widget is constructed, they are placed on special carts which can deliver the widget anywhere in the city. In order for a widget to be exported the carts take the widget to the postal office, where the widgets are packaged and labeled for export. Sometimes widgets don t turn out right and the rejects are sent to the scrap yard where they are broken down for parts or destroyed altogether. The town powers the widget shops and carts from a hydraulic dam that is in the city. The entire city is enclosed by a large wooden fence, only the postal trucks (and citizens with proper passports) are allowed outside the city. Match the parts of the city (underlined) with the parts of the cell. Organelle City Analogy Mitochondria Ribosomes Nucleus Endoplasmic reticulum Golgi apparatus Protein Cell membrane Lysosomes Nucleolus 36
Cell Organelle Review Sheet Fill in Check Boxes Part of the Cell Structure Function Bacteria Plant Animal Cell Membrane Cell Wall Nucleus Nuclear Membrane Nucleolus DNA Cytoplasm RER/SER Ribosomes Golgi Apparatus Mitochondria Chloroplast Vacuole Lysosome 37
Flow Chart Identify organelles found in each All Organisms Domain Prokayote Domain Eukaryote Bacteria Animalia Plantae Fungi Protista 38
Osmotic Solution Note: A RBC is 85% H 2 O and15% Solutes. 1. Osmotic Solution: 100% H 2 O RBC Direction of the Movement of Water What will happen to the cell? 2. Osmotic Solution: 40% H 2 O RBC Direction of the Movement of Water What will happen to the cell? 3. Osmotic Solution: 80% H 2 O RBC Direction of the Movement of Water What will happen to the cell? 4. Osmotic Solution: 85% H 2 O RBC Direction of the Movement of Water What will happen to the cell? 39
5. Osmotic Solution: 90% H 2 O RBC Direction of the Movement of Water What will happen to the cell? 6. Osmotic Solution: 75% H 2 O Direction of the Movement of Water RBC What will happen to the cell? 7. Osmotic Solution: 80% H 2 O 90% H 2O Direction of the Movement of Water What will happen to the cell? 8. Osmotic Solution: 70% H 2 O 70% H 2O Direction of the Movement of Water What will happen to the cell? 40
9. Osmotic Solution: 40% H 2 O 30% H 2O Direction of the Movement of Water What will happen to the cell? For 10-12: = water molecule 10. Osmotic Solution: Direction of the Movement of Water What will happen to the cell? 11. Osmotic Solution: Direction of the Movement of Water What will happen to the cell? 12. Osmotic Solution: Direction of the Movement of Water What will happen to the cell? 41
Background Information: Gummi Bear Osmosis Molecules are in constant motion, and tend to move from areas of higher concentrations to lesser concentrations. Diffusion is defined as the movement of molecules from an area of high concentration to an area of low concentration. The diffusion of water molecules through a selectively permeable membrane is known as OSMOSIS; water molecules move from an area of high concentration to an area of low concentration. Question: How will soaking Gummy Bear candies in distilled water affect the size of the candy? Hypothesis: Materials: Plastic cup Tap water Saturated salt solution 1 Gummy bear Ruler Permanent marker Balance 1 aluminum screen Procedure: Day 1: 1. Label your plastic with your names and mods, using the permanent marker. 2. Find the mass of your bear using the balance and record your data. 3. Use the ruler to measure your bear top to bottom (length), side to side (width) and front to back. Calculate volume (L x W x H) and record your data. 4. Fill your plastic cup ½ way full with tap water. 5. Put your candy bear in the water. 6. Set the cup aside for one day. Day 2 1. After the candy bear has been in the tap water overnight, pour the water with your gummi bear over an aluminum screen into the sink. Be very careful because the candy is now extremely breakable. 2. Blot the screen dry by placing it on a paper towel. 3. While the bear is on the screen, measure your bear top to bottom (length), side to side (width) and front to back. Calculate volume (L x W x H) and record your data. 4. Find the mass of the bear. Do this by placing the entire screen with the bear on the balance. Record the total mass. Then carefully slide the bear back into the empty cup. a. Find the mass of the screen alone and calculate the mass of the bear. Record your data. 5. Cover the bears with the saturated salt solution. Set aside overnight. Day 3 1. Find the mass and dimensions of the bear using the same procedure as noted on Day 2. 2. Record all data. Calculate volumes. 42
Data: Data Table for Mass Mass (g) Mass of screen and gummi bear Mass of screen Before Soaking (Day 1) After Tap Water (Day 2) After Salt Water (Day 3) Mass of gummi bear Data Table for Volume Dimensions Length (cm) Before Soaking (Day 1) After Tap Water (Day 2) After Salt Water (Day 3) Width (cm) Depth (cm) Volume (cm 3 ) 43
Questions & Analysis: 1. What happened to the candy after soaking in tap water overnight? Why? 2. Do you think you would get different results if you used distilled water instead of tap water? (Distilled water has fewer solutes than tap water). 3. What happened to the candy after soaking it in salt water overnight? Why? 4. What do you think would have happened to the bears if, after the last day, they were placed again in tap water? 5. Calculate the percent change in volume after each step of the experiment. a. % change in volume = (final volume initial volume) / initial volume x 100 b. Record calculates below Bear 1 % Change in Water % Change in Salt Water 44
Endocytosis Lab Objective: Using the materials available you will demonstrate how a cell performs a type of endocytosis. Materials: Paper bag String One piece of candy Scissors Procedure: The paper bag represents your cell membrane. The air inside the bag is the cytoplasm. Your cell needs to eat a large molecule, like a protein or starch. You, working as an extension of your paper bag cell, need to get the large molecule (your candy) into the cell without exposing the inside of your cell to the outside air. You may not put the molecule in through the bag opening. You MAY put your hand into the cytoplasm through the top of the bag to help with the procedure. Analysis: 1. What organelle did you create in your paper bag cell during endocytosis? 2. Describe the difference between endocytosis and exocytosis. 3. Draw a detailed, labeled sketch of the process you used to show endocytosis in this lab. You should include a least three steps/stages and explain what is happening in each. Be sure to label the parts of the cell/bag involved 45
Potato Lab Objective: Understand Diffusion and Osmosis Be able to determine the solute concentration of a potato Part A: Diffusion of Iodine and Starch 1. Obtain a 30cm piece of dialysis tubing, tie one end off 2. Add 15ml of Starch solution to the tubing and tie the other end off 3. Fill a 250mL beaker 2/3 rd full of tap water. 4. Add 4 ml of Lugol s solution to the beaker 5. Allow to sit for 30 minutes Bag Beaker Initial Contents Starch Water Water Iodine Solution Color Initial Final 1. What does iodine test for? 2. Which substances are entering the bag? Which substances are leaving the bag? How do you know this? 3. Based on your observations rank the following by relative size, beginning with the smallest: Iodine (IKI), starch, Water (H2O) 46
Part B: Determine the Molarity of a Potato Materials: 50mL Water 50mL 0.2M sucrose 50mL 0.4 M sucrose 50mL 0.6M sucrose 50mL 0.8M sucrose 5 small plastic cups Plastic wrap Procedure: 1. Pour 50mL of each solution in a small plastic cup 2. Use a Number 2 cork borer to cut 3 potato cylinders into 3cm sections. Remove all of the skin 3. Determine the mass of the three cylinders and record the mass in table 1.2 4. Put the 3 cylinders in the cup with water, cover with plastic wrap and let stand overnight. 5. Repeat procedure 2-4 for each remaining cup (0.2M, 0.4M, 0.6M, and 0.8M) 6. Remove the cores from the beaker, blot them gently on a paper towel, and determine their total mass. 7. Record the final mass in the table below. 8. Graph your data on graph on the next page. Data: Contents in Beaker 0.0 M Water Initial Mass Final Mass Mass Difference (initial mass final mass) Percent change in mass (mass difference/initial mass)x 100 0.2 M sucrose 0.4 M sucrose 0.6 M sucrose 0.8 M sucrose Lab Station #7 47
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9. Determine the molar concentration of the potato core. This would be the sucrose molarity in which the mass of the potato core does not change. To find this, add a line of best fit to your graph. Then, the point at which your line crosses 0% change. Molar concentration of sucrose M. 10. Your friend asks you to determine the molar concentration of Gatorade. Design an experiment to test this. 50