The 7 Required Labs 1. Magnification and Cellular Structure – Topic 1.1 2. Estimation of Osmolarity in Tissues – Topic 1.4 3. Factors Effecting Enzyme Activity – Topic 2.5 4. Separation of Photosynthetic Pigments – Topic 2.9 5. Mesocosms and Sustainability – Topic 4.1 6. Monitoring Ventilation in Humans – Topic 6.4 7. Transpiration Rates Using Potometers (HL) – Topic 9.1 1. Magnification and Cellular Structure Objectives a) To use a light microscope and investigate the structure of cells and tissues, including drawing of cells and cellular structures. b) Calculate the magnification of drawings and the actual size of structures and ultrastructures shown in drawings or micrographs. Illustration showing how to prepare a wet mount. Remember to keep your units consistent. Can you use the scale bar for calculations? 1. Magnification and Cellular Structure Practice Makes Perfect… http://www.thinkib.net/biology/page/17083/calculat ing-magnification-and-size 1. Magnification and Cellular Structure Helpful Tutorials Calculating I, A and M http://www.youtube.com/watch?v=wPYBLysk12M http://www.youtube.com/watch?v=NFVSWOaU0f0 &feature=related 1. Magnification and Cellular Structure 2. Estimation of Osmolarity in Tissues Objectives a) Compare hypertonic, hypotonic and isotonic solutions. b) Predict what will occur when plant cells are placed in various solutions. Comparison of Plant and Animal Cells in Solution 2. Estimation of Osmolarity in Tissues Lab Tutorial Refresh Your Memory https://www.youtube.com/watch?v=LeS2-6zHn6M 2. Estimation of Osmolarity in Tissues Osmolarity Virtual Lab http://indstudy1.org/hs/999102059004/Lesson5/Lab5.s wf Complete the Virtual Lab and ask yourself these questions… 1. What are the variables in this experiment (control, independent and dependent)? 2. Explain how this relates to medicine and why cell samples need to be bathed in the same osmotic solution as their contents? 2. Estimation of Osmolarity in Tissues 3. Factors Effecting Enzyme Activity Objectives 1. Determine how different substrate concentrations affect a protease’s activity (measured as the reaction rate). 2. Define the term, ‘denature’. 3. Predict what will occur to the rate of an enzymatic reaction as the substrate concentration increases. Understand the Graphs You should be able to: 1. Draw each of the graphs on the left. 1. Label the X and Y axis of each. 1. Explain, in scientific terms, what is taking place and why. 1. Title each of the graphs. 3. Factors Effecting Enzyme Activity The Experiment You are going to use a commercially available protease, extracted from bacteria. It will hydrolyze most proteins to amino acids. As substrate we will use a solution of skimmed milk powder, which contains the colloidal milk protein casein. This causes the cloudy white appearance of the milk powder, by scattering light. The colorimeter (set on ‘Abs’) will be used to measure the amount of substrate (casein) remaining. 3. Factors Effecting Enzyme Activity Points to Consider… State the RQ for this investigation. Explain how the colorimeter works and predict the results if using varying concentrations of casein. Deduce how the results may relate to the graph below. 3. Factors Effecting Enzyme Activity Virtual Lab http://www.phschool.com/science/biolog y_place/labbench/lab2/intro.html Check out this virtual lab. It will help you revise the key concepts associated with Enzyme Catalysis. 3. Factors Effecting Enzyme Activity 4. Separation of Photosynthetic Pigments Objectives State that chlorophyll is the main photosynthetic pigment. Outline the differences in absorption of red, blue and green light by chlorophyll. Calculate the Rf values for various photosynthetic pigments. An Overview Photosynthesis depends on the absorption of light energy by pigments. These include the chlorophylls and various accessory pigments, which absorb other wavelengths and thus contribute to the overall efficiency of photosynthesis. 4. Separation of Photosynthetic Pigments The Basic Principle This migration of pigment relative to migration of solvent is expressed as a constant, Rf (Reference front). It can be calculated by using the formula: Virtual Lab from Pearson http://www.phschool.com/science/biolog y_place/labbench/lab4/intro.html 4. Separation of Photosynthetic Pigments A Few Thoughts… Discuss the many types of chromatography and state which type we used in this investigation and why. Draw, label and annotate a general diagram of the apparatus used in this experiment. Explain how Rf values can be validated and how scientists can compare their results to known values. Why is this helpful? 4. Separation of Photosynthetic Pigments 5. Mesocosms and Sustainability Objectives To understand that mesocosms are models of larger ecosystems. Define the concept of a ‘closed ecosystem’, one in which energy enters and leaves but matter does not. Ecosystems Compare ‘open’ and ‘closed’ ecosystems. Is any ecosystem really every ‘closed’? Design and build a mesocosm. Discuss how carbon and water cycle through your mecososm. 5. Mesocosms and Sustainability Check out this guy’s ecosystem! David Latimer planted his bottle garden in 1960 and hasn’t watered it since 1972 Read about it here… http://www.dailymail.co.uk/sciencetech/ar icle-2267504/The-sealed-bottle-gardenthriving-40-years-fresh-air-water.html 5. Mesocosms and Sustainability 6. Monitoring Ventilation in Humans Objective To understand that the lungs are actively ventilated to ensure that gas exchange can occur passively. You should be able to design and carry out a simple breathing experiment than analyze your results and draw conclusions? 6. Monitoring Ventilation in Humans Review the Mechanisms of Breathing https://www.youtube.com/watch?v=GD-HPx_ZG8I 6. Monitoring Ventilation in Humans Spirometry Test for Lung Function a) Simple animation showing how Spirometry works b) Extend Yourself https://www.youtube.com/watch?v=hQzN G89pESQ https://www.youtube.com/watch?v=QJcAJ HFqXZg 6. Monitoring Ventilation in Humans 7. Transpiration Rates Using Potometers (HL) Objectives Describe the process of transpiration in vascular plants. Investigate the effect of various environmental factors on the transpiration rate in plants. Transpiration Review https://www.youtube.com/watch?v=U4rzL hz4HHk Complete the Virtual Lab https://www.classzone.com/books/hs/ca/sc /bio_07/virtual_labs/virtualLabs.html 7. Transpiration Rate Using Potometers Discuss environmental factors that affect transpiration rate… http://users.rcn.com/jkimball.ma.ultranet/B iologyPages/T/Transpiration.html 7. Transpiration Rate Using Potometers Additional Resource http://www.thinkib.net/biology/page/16860/lab- protocols-for-new-ib-guide The site above has briefs for all of the IB biology labs.
