3Diffusion & Osmosis Description Dialysis tubing filled with startch-glucose solution in beaker filled with IKI solutionPotato Cores in Sucrose solutionsDetermining solute concentration of different solutions
5Diffusion & Osmosis Conclusions Water moves from high concentration of water (hypotonic or high water potential) to low concentration of water (hypertonic or low water potential)Solute concentrations, polarity and size of molecule affect movement through semipermeable membrane
6Diffusion & OsmosisEssay 1992 A lab assistant prepared solution of .8M, .6M, .4M, and .2M sucrose, but forgot to label them. After realizing the error, the assistant randomly labeled the flasks containing these four unknown solutions as flask A, B, C, and D. Design an experiment, based on the principles of diffusion and osmosis, that the assistant could use to determine which of the flasks contains each of the four unknown solutions Include in your answer: a. a description of how you would set up and perform the experiment b. the results you would expect from your experiment; and c. an explanation of those results based on the principles involved. Be sure to clearly state the principles addressed in your discussion.
12Enzyme Catalysis Description of Honors Biology Lab Measured factors affecting enzyme activityH2O H2O + O2Measured rate of O2 productionDescription of AP Biology LabCatechol QuinoneMeasured rate of light absorbanceIncluded Hydroquinone and resorsinol (isomers)CatalaseClear Polyphenoloxidase Brown
13Enzyme Catalysis Concepts Substrate Enzyme Denaturation of protein Competitive inhibitionAllosteric activation (cooperativity)Experimental designReaction rate w/enzyme vs. reaction rate wo/enzymeOptimum pH or temperature
15Enzyme Catalysis Essay question 2000 The effects of pH and temperature were studied for an enzyme-catalyzed reaction. The following results were obtained.A. How do (1) temperature and (2) pH affect the activity of this enzyme? In your answer, include a discussion of the relationship between the structure and the function of this enzyme, as well as a discussion of how structure and function of enzymes are affected by temperature and pH.B. Describe a controlled experiment that could have produced the data shown for either temperature or pH. Be sure to state the hypothesis that was tested here.Enzyme ActivityEnzyme ActivityTemperature pH
16Try these questions A. Allosteric Inhibition B. Feedback inhibition C. Competitive inhibitionD. Noncompetitive inhibitionE. CooperativityDescribes inhibition by an enzyme that is capable of either activation or inhibiting a metabolic pathway.A reversible inhibitor that looks similar to the normal substrate and competes for the active site of the enzymeThe process by which the binding of the substrate to the enzyme triggers a favorable conformation change which causes similar change in all of the proteins subunits.The process by which a metabolic pathway is shut off by the product it producesBinds to the enzyme at a site other than the active site, causing the enzyme to change shape and be unable to bind substrate.
17Try these questions7. The above graph most accurately depicts the energy changes that take place in which of the following types of reaction? A. hypothermic B. hyperthermic C. endergonic D. exergonic E. free range
18Mitosis & Meiosis Description Cell stages of mitosis Exam slide of onion root tipCount number of cells in each stage to determine relative time spent in each stageCrossing over in meiosisFarther gene is from centromere the greater number of crossoversObserved crossing over in fungus, SordariaArrangement of ascospores
21Sordaria (Ascomycete fungus) One genetic variability is the color of the ascospores.Wild (dark brown)TanHow the ascospores are arranged in the ascus represents if crossing over has occurred.No crossing over:4:4Crossing over:2:4:2 or2:2:2:2Meiosis – where crossing over may occurSporesKaryogamynTwo Hyphae fuse (plasmogamy)Growing on the plates
22You will look at slides of the plates and calculate the percentage of crossover. This can be used to determine map units.
23Mitosis & Meiosis Conclusions Mitosis Meiosis Cell division Growth, repairMaking clonesMeiosisReduction divisionMaking gametesIncreasing variationCrossing over in Prophase 1
24Mitosis & MeiosisEssay 1982 Discuss the process of cell division in animals. Include a description of mitosis and cytokinesis, and of the other phases of the cell cycle. Do not include meiosis. Essay 204 Meiosis reduces chromosome number and rearranges genetic information. a. explain how the reduction and rearrangement are accomplished in meiosis b. several human disorders occur as a result of defects in the meiotic process. Identify ONE such chromosomal abnormality; what effects does it have on the phenotype of people with the disorder? Describe how this abnormality could result from a defect in meiosis.
25Photosynthesis Description Determine rate of photosynthesis under different conditionsLight vs. darkBoiled vs. unboiled chloroplastsChloroplasts vs. no chloroplastsUse DPIP in place of NADP+DPIPox = blue (NADP+)DPIPred= clear (NADPH)Measure light transmittancePaper chromatography to separate plant pigments
26Photosynthesis Concepts Light reaction Experimental design Control vs. ExperimentalChlorophyll and othersChlorophyll aChlorophyll bXanthophyllsCarotenoids
27Photosynthesis Conclusions Pigments Photosynthesis Pigments move at different rates based on solubility and mass in the solventPhotosynthesisLight and unboiled chloroplasts produced highest rate of photosynthesisWhich is the control?
28PhotosynthesisEssay 2004 (part 1) A controlled experiment was conducted to analyze the effects of darkness and boiling on the photosynthetic rate of incubated chloroplast suspensions. The dye reduction technique was used. Each chloroplast suspension was mixed with DPDP, an electron acceptor that changes from blue to clear when it is reduced. Each sample was placed individually in a spectrophotometer and the percent transmittance was recorded. The three samples used were prepared as follows. Sample 1 – chloroplast suspension + DPIP Sample 2 – chloroplast suspension surrounded by foil wrap to provide a dark environment + DPIP Sample 3 – chloroplast suspension that has been boiled + DPIP Data are given in the table on the next slide a. construct and label a graph showing the results for the three samples b. Identify and explain the control or controls for this experiment c. the differences in the curves of the graphed data indicate that there were differences in the number of electrons produced in the three samples during the experiment. Discuss how electrons are generated in photosynthesis and why the three samples gave different transmittance results.
31Cellular Respiration Description Concepts Conclusions Using a CO2 probe to measure the rate of respiration in crickets at different temperaturesConceptsRespirationEndothermic vs. ExothermicExperimental designConclusionsAs temp. decreases, respiration decreasesAs germination (of peas) increases, respiration increases
32Cellular RespirationGermination pea experimentSet upPurpose of KOH
33Cumulative Oxygen Consumed (mL) Cellular RespirationEssay 1990The results below are measuremnts of culumlative oxygen consumption by germination and dry seeds. Gas volume measurements were corrected for changes in temperature and pressurePlot the results for the germinating seeds at 22⁰C and 10⁰C.Calculate the rate of oxygen consumption for the germinating seeds at 22⁰C, using the time interval between 10 and 20 minutes.Account for the differences in oxygen consumption observed between:Germinating seeds at 22⁰C and at 10⁰CGeminating seeds and dry seeds.Describe the essential features of an experimental apparatus that could be used to measure oxygen consumption by a small organism. Explain why each of these features is necessary.Cumulative Oxygen Consumed (mL)Time (min)10203040Germinating seeds 22⁰C0.08.816.023.732.0Dry seeds (non germinating) 22⁰C0.20.1Germinating Seeds 10⁰C126.96.36.1992.5Dry seeds (non germinating) 10⁰C
35Molecular Biology Description Transformation Gel Electrophoresis Insert foreign gene in bacteria by using engineered plasmidAlso insert ampicillin resistant gene on same plasmid as selectable markerGel ElectrophoresisCut DNA with restriction enzymeFragments separate on gel based on size
36Molecular Biology Concepts Transformation Plasmid Selectable marker Ampicillin resistanceRestriction EnzymeGel ElectrophoresisDNA is negatively chargedSmaller fragments travel fasterCorrelate distance traveled with size of fragment
37Molecular Biology Conclusions Can insert foreign DNA using a vector Ampicillin becomes selecting agentNo transformation = no growth on amp+ plate
55Population Genetics Conclusions Recessive alleles remain hidden in the pool of heterozygotesEven lethal recessive alleles are not completely removed from populationKnow how to solve H-W problems!Allele frequencies…solve for p and qGenotypic frequencies…use p2, 2pq, or q2
56Populations Genetics Essay 1989 Do the following with reference to the Hardy-Weinberg model.Indicate the conditions under which allele frequencies remain constant from one generation to the nextCalculate, showing all work, the frequencies of the alleles and frequencies of the genotypes in a population of 100,000 rabbits of which 25,000 are white and 75,000 are agouti. In rabbits the white color is due to a recessive allele, w, and agouti is due to a dominant allele, W.If the homozygous dominant condition were to become lethal, what would happen to the allelic and genotypic frequencies in the rabbit population after two generations?
58Transpiration Description Test the effects of environmental factors on rate of transpirationTemperatureHumidityAir flow (wind)Light intensityOR plants wrapped in plastic wrap, put in the above varying conditions and taking mass over time. Rate at which plant loses mass is equivalent to rate of water loss due to transpiration.
63Circulatory Physiology DescriptionStudy factors that affect heart rateBody positionLevel of activityDetermine whether an organism in an endotherm or an ectotherm by measuring change in pulse rate as temperature changesDaphniaGoldfish
64Circulatory Physiology ConceptsThemoregulationEndothermEctothermQ10Measures increase in metabolic activity resulting from increase in body temperatureDaphnia can adjust their temperature to the environment, as temperature in environment increases, their body temperature also increases which increases their heart rate
65Circulatory Physiology ConclusionsActivity increases heart rateIn a fit individual pulse and blood pressure are lower and will return more quickly to resting condition after exercise than in a less fit individualPulse rate changes in an ectotherm as external temperature changes
68Animal Behavior Description Set up an experiment to study behavior in an organismBetta fish agonistic behaviorDrosophila mating behaviorPillbug/Sowbug kinesis
69Animal Behavior Concepts Innate vs. learned behavior Experimental designControl vs. experimentalHypothesisNumber of trials/subjectsChoice chamberTemperatureHumiditySalinityOther factors
70Animal Behavior Hypothesis development Poor: Better: I think pillbugs will move toward the wet side of a choice chamber.Better:If pillbugs prefer a moist environment, then when they are randomly place on both sides of a wet/dry choice chamber and allowed to move about freely for 10 minutes, then most will be found on the wet side.
76Dissolved Oxygen Description Measure primary productivity by measuring O2 productionFactors that affect amount of dissolved O2TemperatureAs water temp. increases it’s ability to hold O2 decreasesPhotosynthetic activityIn bright light, aquatic plants produce more O2Decomposition activityAs organic matter decays, microbial respiration consumes O2Mixing and TurbulenceWave action, waterfalls and rapids aerate water and O2 increasesSalinityAs water becomes more salty, its ability to hold O2 decreases
77Dissolved Oxygen Concepts Dissolved Oxygen Primary productivity Measured in 3 waysAmount of CO2 usedRate of sugar (biomass) formationRate of O2 productionNet Productivity vs. Gross productivityRespiration