AP Biology Lab Write-Ups The Good, the Bad, and the Ugly AP Biology Lab Write-Ups

Pre-Lab Quiz (5 points) Score from your pre-lab quiz counts in lab report score Read your lab in advance and come in familiar with purpose, background, variables and procedures!

Title (2 points) Should be concise and explain the purpose of the experiment Use “The Effect of ____ on _____” format

Bad or good? Why? Pea Respiration Lab Cellular Respiration Lab AP Lab 6 The Effect of Temperature and Germination or Non-Germination on Cell Respiration

Title 2 1 Grade Title present, concisely describes purpose of experiment Title present, but not descriptive of experiment’s purpose No title present  

Abstract (2 points) …back to this later… Will typically be the last thing you write for your report

Background (3 points) Provide known, PERTINANT information about the experiment, should include information about variables (even if not stated directly) Helps reader understand the experiment that you have conducted. Important terms should be defined in the section Be sure to cite ALL sources used within the text of the background

Bad or good? Why? Beans contain a carbohydrate known as oligosaccharides and when broken down in the intestines, it produces gas. Enzymes work under normal conditions but can denature when PH levels fluctuate. The independent variable in this lab was the PH level of the liquids added to the Beano and bean solutions. The dependent variable was the enzyme activity if there was any at all. A test tube with no solution is kept as the constant and it helps determine if the Beano was working properly.

Bad or good? Why? For the body to perform its daily functions and to continue to run, it requires energy. The preferred energy choice, in this case, is glucose. The body is able to convert the complex molecule into ATP (adenosine triphosphate), the common carrier of chemical energy in the cell. In order for the conversion to occur, the body cells will split glucose molecules to transfer the energy to ATP through cellular respiration. Cellular respiration occurs in two basic stages: glycolysis and aerobic respiration. During glycolysis, a small amount of ATP is produced when the glucose is broken down into pyruvate. The pyruvate then passes through aerobic respiration, producing a large amount of ATP, or anaerobic fermentation, producing a significantly smaller amount of ATP. When oxygen is present, the ATP will be produced and excess hydrogen will bind to make water molecules. If oxygen is not present, either lactate of ethanol and carbon dioxide are produced. The overall equation for the breakdown of glucose is as follows: Glucose+ Oxygen → Carbon Dioxide + Water+ Energy (ATP). The complete oxidation of glucose by cellular respiration yields to a total of 36 ATP, allowing the cell to have more energy sources. The physical laws of gases are represented in the equation of PV= nRT. The components are as follows: pressure (P), volume (V), number of molecules (n), gas constant (R), and temperature (T). This general gas law has specific characteristics that it can be identified with. Given a constant temperature and pressure, the volume and pressure of the gas is directionally proportional to the number of molecules of gas present. Considering this, a constant number of gas molecules and volume inversely creates a pressure proportional to the volume. If the temperature is changed, while the gas molecules remain constant, the pressure and/or the volume will change in direct relation to the temperature. Gases also flow from high-pressure areas to those of low pressure. Experimenters chose to manipulate the waterbath’s temperature as the independent variable by using a hot and a room temperature waterbath. The peas’ amount of cellular respiration rates change in correspondence to this variable change, allowing these values to be the dependent variable. Throughout the experiment, there is a respirometer of only glass beads, considering they are beads they will not consume oxygen, allowing for the experimenter to have a control to compare the respiring peas. The temperature of the waterbaths also always remained constant to avoid any data malfunctions or inconsistencies. All respirometers also had the same volume of peas; nongerminating peas had the help of glass beads to match the volume of the larger germinating peas.

Purpose (2 points) What is the specific purpose of the lab? Question or statement

Bad or good? Why? The purpose of this lab is to test how temperature effects the rate of cellular respiration in germinating and non-germinating peas. How does a change in temperature effect how fast cellular respiration occurs?

Hypothesis (2 points) If, then, reason format TESTABLE

Bad or good? Why? If pre-soaked and dry peas are exposed to higher temperatures, then they will experience a decrease in the rate of cellular respiration because increased temperatures denature the enzymes involved in cellular respiration and render them non-functional. If dry peas and wet peas are in a hot water bath, they will not have cellular respiration.

Introduction Background Purpose Hypothesis 3 2 1 Grade Grade The background provides important information and is relevant to the lab, includes variables. The background provides important information and is relevant to the lab, does not include variables The background is present but does not provide relevant information and/or variables The background is not given.   2 1 Grade The purpose accurately describes the reason for doing the lab The purpose is incorrect or unclear. The purpose is not given.   2 1 Grade Hypothesis is a testable statement in if, then, reason format The hypothesis is not testable or is given using incorrect format. The hypothesis is not given.  

Results (8 points) Data table(s) – 4 points Don’t forget a title (should mimic lab title format) Include all units and labels

Bad or Good? Why? Table 1: The Effect of Temperature Change on Germinating and Non-germinating Peas’ Oxygen Consumption   Germinating Peas Nongerminating Peas Glass Beads Vials Temp (℃) Time (min) Reading (ml) Diff. Corr. Diff. Vials 1-3 15 0.34 ---- 0.15 5 0.23 -0.11 0.08 0.01 -0.14 0.11 0.12 -0.03 10 0.24 -0.10 0.02 0.06 0.07 -0.08 0.0 -0.15 0.05 20 25 0.04 30 Vials 4-6 35 0.73 0.70 0.80 32 0.92 0.19 0.39 0.85 0.35 1.0 -0.20 0.27 0.47 0.95 0.25 0.45 0.30 .8 0.50

Bad or good? Why? Transpiration Data Type Monday Tuesday Wednesday   Tuesday Wednesday Thursday Friday Control 82.39 Mass 64.46 57.32 58.60 62.23 Cum∆(g) 17.73g 25.07 23.79g 20.16g % Change (cum) -21.8% -30.4% -28.9% -24.5% Light 87.3g 63.99 51.72 34.86 24.44 23.31 35.58 52.44 63.16 -26.7% -40.8% -60.1% -72.3% High Humidity 87.9 57.43 55.55 74.35 105.23 30.47 32.35 13.55 -17.33 -34.7% -36.8% -15.4% 19.7% Fan 87.7 59.09 56.75g 73.88 68.44 28.67 31.01 13.88 19.32 -32.7% -35.3% -15.8% -22% Dark 94.07 60.94 57.36 72.23 94.88 33.13 36.71 21.84 -0.81 -35.2% 39% -23.2% 0.9% Gravity 76.7 62.53 60.5 58.85 58.33 14.17 16.2 17.85 18.37

Results (8 points), cont. Graph(s) – 4 points Almost ALWAYS line graphs Don’t forget a title (should mimic lab title format) Include all units and labels, keyed when appropriate Watch how it is formatted - IV on x-axis, DV on y-axis

Bad or good? Why?

Bad or good? Why?

Results Data tables Graphs 4 3 2, 1 Grade Grade Both qualitative and quantitative data given. Tables are correctly labeled and include units in appropriate places. Both qualitative and quantitative data are given. Labels or units in tables are either missing or incorrect. Qualitative &/or Quantitative data is missing and the tables are poorly constructed, have missing labels, units, or data. No data is given   Data tables Graphs 4 3 2, 1 Grade Graphs are correctly titled, labeled and include units in appropriate places. Graphs titles, labels or units in are either missing or incorrect. Graphs are poorly constructed, have missing labels, units, or data. No graph is given  

Bad or good? Why? The data that was collected confirmed the hypothesis by showing the greatest overall percent change in the mass of the plant belonging to the plant whose variable tested was light. The plant kept in the light saw a percent change of -72.3% the drop in weight was a lot steeper compared to other plants with different variables. The plant with the second highest percent change was the plant that was the control. At the end of Friday the percent change in mass was -24.5%. The plant that saw the smallest drop in mass was the plant with the independent variable of darkness.

Bad or good? WHY? The hypothesis was confirmed; the plant that experienced the greatest amount of water loss. The plant that had the least water loss was the plant in the high humidity environment. This means that there is a relationship between transpiration and the environment.

Conclusion & Discussion (11 points), cont. Errors – 2 points Include how these impacted results! Include experimenter and experimental errors Suggestions for improvement – 2 points Should reference the errors you named!

Bad or good? Why? During the experiment the dye that was used to allow students to visually observe the flow of water into the respirometer had instead dissipated out, causing accurate readings to become more difficult. A student had lifted the vial and respirometer from the bath to fix the problem by re-inserting dye, however this only caused the readings to change due to the presence of oxygen into the resiprometer, again generating miscalculated readings. Prior to submerging the vials and the resiprometer in the water bath, students should make sure that a sufficient amount of dye is inserted into the tip of the respirometer. In the case of excessive dissipation of the dye, there will still be an adequate supply that will remain in the respirometer to ensure accurate and visible readings of the flow of water into the respirometer.

Bad or good? Why? It is entirely possible for some of the KOH to have gotten on the sides of the vials or that the milliliters of water were not exactly 50ml when measured. This can be fixed by absolute concentration on the experiment and its procedure.

Conclusion Conclusion Statement Analysis of Results 2 1 Grade Grade Statement adequately explains the results of the lab Statement present, but does not explain results of lab No statement data given.   4 3, 2, 1 Grade States whether hypothesis was supported or rejected citing specific data. States whether hypothesis was supported or rejected but cites general data/trends. No statement of hypothesis or data given.  

Conclusion Identify errors Suggestions for improvement 3 2 1 Grade Grade 2 sources of error (experimental AND experimenter) are provided as well as how it impacted results 2 sources of error (experimental AND experimenter) are provided, but not how it impacted results 1 source of error given, or missing how errors impacted results No sources of error given or impact on results   2 1 Grade Discusses how procedure could be altered to improve results; addresses errors previously stated. Discusses how procedure could be altered but not how this would improve results; improvements do not relate to previously stated errors. No improvements or impact on results given.  

Bad or good? Why? Oxygen consumption in the respirometers with germinating peas was greater than that in respirometers with non-germinating peas. Respiration rate was also affected by temperature. Respiration occurred at a faster rate in the respirometers in the warm water bath.

Bad or good? Why? In this experiment the vial with germinating peas had the greatest consumption of oxygen. This is because germinating peas carried out a more rapid process of cellular respiration than the non-germinating peas. This is due to their need for energy to continue growing. The beads served as a control and carried out no cellular respiration, confirming that cellular respiration is a process only performed by living organisms. The non-germinating peas require less energy than the germinating peas so the dry peas carry out a slower process of cellular respiration. This in turn caused less oxygen to be consumed in the vials with non-germinating peas than the vials with germinating peas. The higher temperature an increase in kinetic energy of the molecules involved in cellular respiration. This resulted in a higher rate of cellular respiration which in turn caused a greater consumption of oxygen.

Questions Various points – typically 5 points Determined by instructor Question and answer included in lab!

Questions All questions written out. Answers to each question are correct.

Bad or good? Why? 1. According to your graph, what happens to the rate of oxygen consumed by germinating peas over time? What does this indicate to you? The germinating peas consume more and more oxygen over time meaning that they are able to go through more cellular respiration than the non-germinating peas. 1. The structures utilized during this process are the xylem, stomata, and the roots of the plant.

Literature Cited (3 points) Minimum of 2 sources should be cited Can include the lab handout itself, websites used, textbook, etc. In text citations should be included where appropriate (usually in background info) Use proper MLA or APA format!!!!

Bad or good? Why? “Cellular Respiration Lab Activity”. Ward’s. Handout. N.d. Print. AP Lab Sheet "Understanding What Factors Affect Plant Transpiration." Bright Hub. The Encyclopedia of Earth, 7 Feb. 2010. Web. 22 Sept. 2014.

Literature Cited 3 2 1 Grade Grade 2 sources are cited appropriately, but not cited within text 2 sources are cited appropriately, but not within text. Only 1 source cited or citations are not appropriate No sources cited.  

Language (2 points) Proper spelling, grammar, etc. PASSIVE VOICE (third person)!!!!!! Past tense

Bad or good? An error during the experiment was that the timer was not checked at precise intervals. To avoid this error in future experiments, experimenters need to pay close attention to the time and record data at the correct intervals. I think that one error in the experiment was because we forgot to check the timer at precise intervals. In future experiments, I would make sure that I checked the timer when I was supposed to.

Language 2 1 Grade All grammar/spelling/punctuation correct and very well-written. All sections in order, well-formatted, very readable. No usage of pronouns (I, we, you, etc.) No more than 3 grammar/spelling/punctuation errors, well-written, all sections in order, formatting could still be improved. Very few pronouns used. More than 3 spelling/grammar errors, not well-written, sections out of order, not legible, sloppy formatting, some pronoun use.  

Abstract (3 points) A BRIEF summary of the purpose, methods, and results of your experiment Reader would see what they are about to read in your report 3 sentences: purpose, methods, results 100 words or less

Bad or good? Why? Students will demonstrate and observe the effects temperature and germination has on a pea’s cellular respiration. Respirometers with either germinating, non-germinating or water beads are placed into either a hot or room temperature waterbath and are observed to see cellular respiration rates. The germinated peas in the warm waterbath consumed the most oxygen.

Bad or good? Why? In this lab, students will apply their background knowledge of cellular respiration and its several components: glycolsis, pyruvate oxidation, oxidative phosphorylation, substrate-level phosphorylation, the citric acid cycle (Krebs Cycle), the electron transport system, and physical gas laws related to the understanding of a respirometer. Students will investigate the effect of temperature and germination or non-germination on cell respiration, and the relationship between dependent and independent variables. The lab will mandate that students place vials containing germinating peas, non-germinating peas, and glass beads with a respirometer in a heated and room temperature water bath to demonstrate the relationship of gas laws to the function of a respirometer as well as to calculate the rate of cell respiration using the derived data from the experiment. Students will determine that temperature does directly correspond to the rate of cellular respiration since higher temperatures yield increases in enzyme and metabolic activity of an organism, therefore increasing the rate of cellular respiration.

Abstract 3 2 1 Grade Is fewer than 100 words and includes a purpose, procedure and conclusion statement Is fewer than 100 words and includes 2 of the 3 required components The abstract is too long or is missing 2 required components. The abstract is not given.