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Teaching the Concepts of Genetics. Presented by: Keith Madden Alvin Essenberg Kasi Bolden Susan Rathwick. Drosophila Basic Studying the Monohybrid Cross. Cost: $87.95 Presented by Alvin Essenburg. Kit Includes. Anesthetizer Sorting brushes Culture containers
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Teaching the Concepts of Genetics Presented by: Keith Madden Alvin Essenberg Kasi Bolden Susan Rathwick
Drosophila Basic Studying the Monohybrid Cross • Cost: $87.95 Presented by Alvin Essenburg
Kit Includes • Anesthetizer • Sorting brushes • Culture containers • Instant Drosophila medium • Teacher's Notes • Supplies Needed: • Wild and Sepia Drosophila cultures (not part of cost) • Disecting Scope (Magnifying glasses are difficult to use)
Procedure Step 1: Remove all Sepia adults from culture • Mature adult females can't be used because they can store sperm for their entire life Sepia
Procedure 2. When new fruit flies hatch in Sepia culture: • Remove all adults in Sepia culture within 6-8 hrs. • Sort and isolate females for 3-4 days in new culture tube. Sepia Sepia females Sepia males
Procedure 3. Setup new culture tubes. • Place 5 Sepia female and 5 Wild males in each. • (P generation) Sepia Female Wild Sepia Female x Wild Male
Procedure Flies will breed and lay eggs. Sepia Female x Wild Male
Procedure 4. After 7-10 days, before new flies hatch, remove all adults. Sepia Female x Wild Male
Procedure 5. New flies will be the F1 generation, remove adults within 6-8 hours and tally each species • All will be Wild (Red eyes) F1 generation
Procedure 6. As new F1 generation flies hatch, place 5 male and 5 female F1 in a new culture. F1 generation F1 x F1
Procedure 6. As new F1 generation flies hatch, place 5 male and 5 female F1 in a new culture. F1 generation F1 x F1
Procedure 7. Remove adults within 6-8 hours and tally each species • New flies will be the F2 generation. • About ¼ should hatch as Sepia F1 x F1
Evaluation Pros • Students get to actually do a monohybrid cross • High interest lab Cons • Very time consuming and scheduled • Medium grew mold easily • May be difficult for students to sort flies at home • Could choose different varieties that can't fly
Protein SynthesisFlinn ScientificFB1760$46.30 Kasi L. BoldenWashington H.S.
Protein Synthesis Objective: The objective is to show how individual genes are translated into protein chains. Experiment overview: In this activity, models of mRNA, tRNA, amino acids and ribosomes will be used to better understand protein synthesis.
Teaching Tips Students should know where transcription and translation occurs. Student should know that the triplet of bases brought by tRNA are anticodons and is complementary to an mRNA codon. Students should have a basic understanding of nucleic acids, transcriptions and translation before beginning the activity. A summary discussion after each step may be worthwhile to be sure of students’ comprehension before moving on to the next step.
Materials Ribosome mRNA strand tRNA Amino acid round chips, 20 (10) Label, round 20(10) Marker Tape, double stick Tape, transparent *Protein Synthesis Worksheet( not provided)
Protein Synthesis Questionnaire Does the lab present protein synthesis in the proper sequence so students will gain understanding? Yes or No Are there any materials that can be substituted or eliminated? Do you think the first and second steps of the procedure are necessary? Do you feel it’s necessary to teach the importance of 3’ & 5’? Please list any flaws in this activity. List any flaw that may cause confusion
Analyzing Population Growth Kit Carolina Item #251012 Price $99.95 Materials for 32 students working in groups of 4
Objectives/Learning Goals • Students analyze the effects of resources on yeast as they explore population growth.
Objectives/Learning Goals • Develop the skills necessary to design & perform scientific investigations • Produce a testable hypothesis • Investigate the effects of environmental conditions on a model lab species
Objectives/Learning Goals • Derive the relationship between resource quality and population growth • Develop connections with the key concepts of logistic and exponential growth, carrying capacity, and population pyramids
32 petri dishes Parafilm® 4 yeast malt media bottles 100 pipets (graduated) 9 sterile pipets 9 yeast packets 18 g lactose 30 ml excess nitrate 2 sheets black construction paper 8 fine-point permanent markers 8 inoculating loops 40 test tubes 16 Lazy-L-Spreaders™ Materials Supplied
Safety glasses Heat-resistant gloves 8 glass beakers, 400ml 8 Bunsen burners 8 flint lighters 1 gallon distilled H2O 8 hot plates 8 dissecting scopes 8 thermometers Laboratory balances Weight boats 2 spatulas 8 graduated cylinders, 100 ml 8 flasks, 125 ml Materials Not Supplied
Age ratio Carrying capacity Demographics Emigration Population pyramid Exponential growth Immigration Logistic growth Population resources Background Vocabulary
Lab Could Be Used During the Study of….. • Interdependence of organisms • Behavior of organisms • Population growth • Natural resources • Environmental quality • Natural & human-induced hazards
Background Knowledge • Exponential growth – if a population is not limited by resources, and increases at a faster rate as the number of individuals increases.
Logistic growth - describes a growth rate that levels off and is maintained.
Population pyramid – graph showing how the total population is split among various age brackets.
Yeast- microscopic, unicellular fungi able to live with our without O2
Plate streaking techniques
Activity #1 • Requires students to fill 3 test tubes with yeast and either glucose or lactose as a food source. Test tubes are covered and placed in a hot water bath 35-40° C. • Students will record growth in 2 minute intervals for a total of 10 minutes • A fourth tube is filled as a control group. • Results are shared among the teams
Activity #2 • Requires students to choose 1 of four treatments they hypothesize will produce the most growth in the yeast population • Treatments • Glucose • Lactose • Nitrate • Light intensity
Students are required to write their hypothesis and reasoning for this in their lab notebook • Procedures are provided for each of the 4 treatments students will choose. • After the plates are prepared they will invert and leave for three days
After 3 days the groups will decide how to rate the growth in the petri dishes, writing down the comparative data in their lab notebook and creating a bar graph to display the data • Students analyze the results
Prior to Step 1 (follow the first step in Activity 1) • Warm up a beaker of 40 mL distilled water to about 30-40°C. • Remove from heat and add 3.5 g of yeast • Cover it with a 4-square block of Parafilm® • Let yeast activate for 10 minutes
Comparative Proteomics Kit I: Protein Profiler Module Bio-Rad 166-2700EDU 32 students List Price: $203.75 Refill: $ 94.00
Comparative Proteomics Kit I: Protein Profiler Module Laemmli sample buffer Kaleidoscope™ prestained standards Tris-glycine-SDS electrophoresis buffer Bio-Safe™ Coomassie stain for proteins Actin and myosin standard Dithiothreitol (DTT) Pipet tips for gel loading Test tubes,transferpipets, gel-staining trays, test tube holders Teacher's Guide, Student Manual, and graphic Quick Guide
Required Accessories Not Included in Kit Fish samples 5–8 types Adjustable micropipets, 2–20 µl Power supplies Water bath If using polyacrylamide gel electrophoresis:Vertical gel electrophoresis chambers Precast polyacrylamide gels
Can Biomolecular Evidence Be Used to Determine Evolutionary Relationships? • Traits are the result of Structure and Function • Proteins determine structure and function • DNA codes for proteins that confer traits • DNA -> RNA -> Protein -> Trait • Changes in DNA lead to proteins with: • Different functions • Novel traits • Positive, negative, or no effects • Genetic diversity provides pool for natural selection = evolution
Explore Biochemical Evidence for Evolution • Analyze protein profiles from a variety of fish • Study protein structure/function • Use polyacrylamide electrophoresis to separate proteins by size • Construct cladograms using data from students’ gel analysis • Compare biochemical and phylogenetic relationships. • Sufficient materials for 8 student workstations • Can be completed in three 45 minute lab sessions
Workshop Timeline • Introduction • Sample Preparation • Load and electrophorese protein samples • Compare protein profiles • Construct cladograms
Sample Preparation Lab Period 1 Label one 1.5 ml fliptoptube for each of five fish samples. Also label one screwcapmicro tube for each fish sample. Add 250 μl of Bio-Rad Laemmli sample buffer to each labeled fliptopmicrotube. Cut a piece of each fish muscle about 0.25 x 0.25 x 0.25 cm3 and transfer each piece into a labeled fliptop tube. (Close the lid!)
Sample Preparation Lab Period 1 (con’t) Agitate the tissue in the sample buffer; Incubate for 5 minutes at room temperature. Carefully transfer the buffer labeled screwcaptube. Do not transfer the fish! Heat the fish samples in screwcapmicrotubes for 5 minutes at 95°C. Freeze until lab period 2.
Electrophoresis Lab Period 2 Heat extracted fish samples and actin and myosin standard to 95°C for 2–5 min. This dissolves any detergent in the extraction (Laemmli) buffer that may have precipitated upon freezing.
Electrophoresis Lab Period 2 (con’t) Load your gel: • 5 μl Precision Plus Protein Kaleidoscope prestained standards (Stds) • 10 μl fish sample 1 • 10 μl fish sample 2 • 10 μl fish sample 3 • 10 μlactin and myosin standard (AM)