TAMPA PREPARATORY SCHOOLBiology Lab Manual Written / Edited By Mr. Chris Maraghy
Introduction Source: http://www.flickr.com/photos/uonottingham/8447712632/ i
WELCOME!! Welcome to laboratory work for Biology classes at Tampa ! The benefits you gain from lab exercises depend entirely onPreparatory School. Students often find lab exercises to be one of your attitude, enthusiasm, and curiosity. This is a fantastic chancethe more enjoyable parts of science classes. Throughout the school for discovery on your own without relying on the teacher or book.year you will be conducting a variety of laboratory exercises in realtime as well as in the virtual world. This manual has been Additional information and resources for lab work can be found on the class Haikuprepared as a source of information, a reference guide and a sitecompilation of all the labs you will be conducting.! Laboratory work serves a number of important functions inyour study of the sciences. These exercises provide an opportunityto see how topics tie together as well as how they apply to the realworld. As such, you are responsible for the material covered inthese labs as it builds upon and reinforces topics discussed in thebook or in class. Lab work also gives you the opportunity to carryout experiments or tests that allow you to follow and appreciatethe methods used by scientists throughout the world.! When you come to class on a lab day, you should be preparedto work. This means that you have done the required backgroundwork, you are dressed appropriately, and you have any materialsthat you “are required to have for the lab. The lab period willtypically start with some preliminary instructions from the teacherbefore you get right to the activity of the day. It is imperative thatthe class gets started immediately so that you will have plenty oftime to accurately and precisely complete the work and clean up atthe end.! ii
COPYRIGHT S© 2017 - T.P. Marine PublishingVersion 2.3This Publication Is Supplied As A Reference For Current MembersOf Tampa Preparatory School Biology Classes. The MaterialContained Herein May Not Be Duplicated Or Copied WithoutExpress Permission T.P. Marine Publishing. Tampa Prep BiologyLogo By Chris Maraghy Is Licensed Under A Creative CommonsAttribution-NonCommercial-NoDerivs 3.0 United States License. iii
CHAPTER 1Lab Safety Source: http://www.flickr.com/photos/malcubed/116185340/ 5
SECTION 1Safety in the Lab! While lab work can be both fun and exciting, it is importantto be aware of potential hazards to you, your classmates or yourteacher. The wellbeing of those around you begins and ends withyou. Lab time is not for socializing or goofing around and it isimperative you stay focused on your work at all times. If therehappens to be a waiting period, you can use the time to startcleaning up, check over your results or start thinking about anyfollow-up work. Accidents or injuries can and sometimes dohappen in lab. By cooperating with the teacher and usingcommon sense, students can prevent these accidents or injuries.! In general it is imperative that you study all procedures andunderstand any safety concerns before you start lab work. If atany time you are unsure of what to do, how to use a piece ofequipment or something does not seem quite right, always askyour teacher. At the end of a lab part of safety includes cleaningup. All equipment must be scrubbed with soap and water,thoroughly dried, returned to the location you obtained them andfinally wipe down the lab desk .! What follows is a list of specific safety rules designed for thevarious types of activities you will be participating in and anagreement that signifies that you understand the rules and the rolethat you play in ensuring everyone's safety. 6
SECTION 2Laboratory Safety Rules! Science is a hands-on, laboratory class. You will be doing 6. Conduct yourself in a responsible manner at all times in themany laboratory activities, which require the use of chemicals, laboratory. Never fool around in the laboratory.glass and heat. To ensure a safe science classroom, a list of ruleshas been developed and provided to you in this student safety 7. Report any accident (spill, breakage, etc.) or injury (cut, burn,agreement. These rules must be followed at all times. Both you etc.) to the instructor immediately, no matter how trivial it mayand a parent or guardian must sign a copy of the agreement and appear. Know the locations and operating procedures of allturn it in to your teacher before you can participate in the safety equipment including the first aid kit, eyewash station,laboratory. Keep this list in your science notebook as a constant safety shower, and fire extinguisher. Know what to do if there isreminder of the safety rules. a fire drill.1. When entering the classroom, do not touch anything in the 8. Keep hands away from face, eyes, mouth, and body while using laboratory are until you are instructed to do so. chemicals or preserved specimens. Wash your hands with soap and water after performing all experiments. Clean (with2. Bring only your laboratory instructions, worksheets, and detergent), rinse, and wipe dry all work surfaces (including the something to write with into the work area. sink) and apparatus at the end of the experiment.3. Follow all written and verbal instructions carefully. If you do 9. All chemicals in the laboratory are to be considered dangerous. not understand a direction or part of a procedure, ask the Do not touch, taste, or smell any chemicals unless specifically instructor before proceeding. instructed to do so.4. Do not eat food, drink beverages, or chew gum in the 10.Examine glassware before each use. Never use chipped or laboratory. cracked glassware. Never use dirty glassware. Never handle broken glass with your bare hands. Use a brush and dustpan to5. Experiments must be personally monitored at all times. Do not clean up broken glass. Place broken or waste glassware in the wander around the room, distract other students, or interfere designated glass disposal container. with the laboratory experiments of others. 7
11.When removing an electrical plug from its socket, grasp the plug, not the electrical cord. Hands must be completely dry before touching an electrical switch, plug, or outlet. Report damaged electrical equipment immediately.12.If you do not understand how to use a piece of equipment, ask the instructor for help.13.Handle all living organisms used in a laboratory activity in a humane manner. Preserved biological materials are to be treated with respect and disposed of properly.14.Any time chemicals, heat, or glassware are used, students will wear laboratory goggles. There will be no exception to this rule! If you wear contact lenses, your instructor will provide special goggles. Lab Aprons have been provided for your use and should be worn during laboratory activities.15. Dress properly during a laboratory activity. Long hair, dangling jewelry, and loose or baggy clothing are a hazard in the laboratory. Long hair must be tied back and dangling jewelry and loose or baggy clothing must be secured. Long pants and shoes that completely cover the foot are required. No sandals or shorts allowed. http://nagrascience9.wikispaces.com/Interactive+notes+Lab+Safety 8
SECTION 3Laboratory Safety AgreementPlease answer the following questions so your teacher knows if Dear Parent or Guardian:any of these things will affect your ability to conduct laboratorywork. We feel that you should be informed regarding the school’s effort to create and maintain a safe science classroom / laboratoryDo you wear contact lenses?! Yes! No environment. With the cooperation of the instructors, parents, and students, a safety instruction program can eliminate, prevent, andAre you color blind?! ! ! Yes! No correct possible hazards. You should be aware of the safety instructions your son / daughter will receive before engaging inDo you have allergies?! ! Yes! No any laboratory work. Please read the list of safety rules they have been provided. No student will be permitted to perform! ! If yes, list specific allergies: ________________________ laboratory activities unless this agreement is signed by both the student and parent / guardian and is on file with the teacher. YourI, _____________________ (student’s name), have read and agree signature indicates that you have read this Laboratory Safetyto follow all of the safety rules set forth in this agreement. I realize Agreement, are aware of the measures taken to insure the safety ofthat I must obey these rules to insure my own safety, and that of your son / daughter in the science laboratory, and will instructmy fellow students and instructor. I will cooperate to the fullest your son / daughter to uphold his / her agreement to follow theseextent with my instructor and fellow students to maintain a safe rules and procedures in the laboratory.lab environment. I will also closely follow the oral and writteninstructions provided by the instructor. I am aware that any Parent / Guardian Signature _________________________violation of this safety agreement that results in unsafe conduct inthe laboratory or misbehavior on my part, may result in being Date _____________removed from the laboratory, detention, receiving a failing grade,and / or dismissal from the laboratory portion of the course. This document is available for download here: https://drive.google.com/ open?id=0B_eOLz4xA35jemUzVERxWEV2S2MStudent Signature _____________________________ Date ________ 9
CHAPTER 2Methods of Science Source: http://www.flickr.com/photos/worldeconomicforum/3911111637/ 10
SECTION 1The Scientific ProcessFigure 2.1 A High School Science LaboratorySource: http://www.flickr.com/photos/jamesbt/3297092404/! Every day you face a variety of problems, which you must and how each part should be completed. While they are listed insolve. It’s always best to have a plan to solve those problems. For a specific order, remember that in the real world, science is notscientists, the standardized plan for studying topics and finding necessarily this orderly.answers to questions is called scientific methods. The use ofscientific methods helps to eliminate confusion and conflicts Initial Observations:between scientists and, in general, makes research legitimate. Inthe sections that follow you will learn about the steps involved ! Every process needs a starting point and for scientific methods, the process often begins with some initial, personal 11
observations. This involves collecting as much information about Hypothesis:a subject using as many of your senses as possible; see, hear, smell,touch, taste. Obviously certain senses are more valuable than ! Once you have decided upon a question to be answered byothers and in certain situations it would be advisable not to use your experiment, the next step is to develop a hypothesis. Asome of them. This information will help you to develop hypothesis is an educated prediction that is testable and specific.inferences, ideas about the subject that are supported by your Since you have been educated by both observations andobservations. You will also be asking questions that you might background you should be able to make a fairly accuratewant to study further and these will become the foundation of prediction about the outcome of your experiment. The hypothesisyour experiment. It is important to realize that even the best needs to include some very specific pieces of information: 1)scientists need to stay as objective as possible and not let personal subject – who or what you are studying; 2) independent variableopinions or experiences affect observations. While nearly – the one condition you will be changing in the experiment; 3)impossible to eliminate completely, a good scientist is aware of dependent variable – what will change because of thetheir biases and will reduce their effect as much as possible in all independent variable and how. [Note: In some of the lab exercisesstages of research. you will perform this year there may be multiple independent variables. As long as only one condition is changed at a time, it isBackground Research: still considered to be a controlled experiment.] You should always state your hypothesis with confidence and not include things such! Are you likely to be the first person to study a particular as \"I think…\" or \"I believe….\" Ex. “A 10oC increase in temperaturesubject? Probably not. It makes sense, therefore, to find out what will slow the growth rate of fish.”other scientists have previously discovered about the subject. In sodoing, you will be able to answer many of the questions you asked Designing an Experiment:during your initial observations and narrow your focus. This stepis easily interchanged with initial observations. ! Once you have developed your hypothesis, you need to create an appropriate method for testing it. This organizedProblem: procedure to test a hypothesis is an experiment. There are many things that need to be considered when designing an experiment! After your initial “observations and background research you so the results will be accurate and precise.should be pretty well focused on what you would like to study. Ultimately you have one question to answer, called the problem. Data: There are two types of data that may be collected during an Ex. “How does temperature affect the rate of growth in fish?” experiment; quantitative and qualitative. Quantitative data are numbers, often measurements, which can be put in to graphs and charts. When making measurements it is important to use SI units 12
(a.k.a. the metric system), which is used by scientists throughout While others may later follow your work, ultimately you need tothe world. Not only are SI units more manageable than U.S. decide how many times you will conduct the experiment.customary units since they are based around 10 (mili-, deci-, kilo-, Sometimes this means that you will have to run through the entireetc), this is yet another idea that ensures that all scientists are on procedure several times. Quite often, however, it is possible to usethe same page. This is typically the preferred type of data, as it multiple test subjects at the same time. Using multiple test subjectstends to be more accurate and objective. The other type of data is in one experiment allows for a number of benefits. First, it savesqualitative. This includes drawings and descriptions of time from having to test one individual at a time through the entirecharacteristics or behaviors. experiment. Second, if you are testing one subject at a time and something happens to that test subject, you will have to start theVariables: The various conditions within the experiment are entire experiment over again. Finally, using multiple test subjectsknown as variables. Two of these conditions were discussed will provide you with an average especially if there are testbriefly in the section about hypotheses. The independent variable subjects that do not follow the typical pattern of results.is what you will be changing during the experiment to see how itaffects the test subject. There is only ever one independent ! The steps above represent the majority of designing anvariable or you will not know what specifically is causing the experiment. The only thing left to do is to write out a complete listresult. The dependent variable is how the test subject changes as a of materials that will be needed as well as the step by stepresult of the independent variable. All other conditions in the procedure that will be followed to successfully complete theexperiment will stay the same throughout and are known as experiment.constants. ! It is important to keep in mind as you go through this processGroups: Every experiment has a minimum of two separate groups that your ultimate goal is to create a controlled experiment. Thisof test subjects. The first group is the control group. The control means there is a control group and only one independent variable.group is test subjects under normal conditions. This group is Overall, a well-controlled experiment will stand up better toimportant so when some condition is changed, we know the effect scrutiny from your peers.it has had by comparing to the results of the control. Any othergroup of test subjects is an experimental group. An experimental Carrying Out Your Experiment:group includes those test subjects that experience the independentvariable. ! Once you have carefully designed an experiment, the obvious next step is to actually follow the procedure and find out what theTrials: Any good experiment will be performed repeatedly to results are. It is in carrying out an experiment that you will makeprovide as much evidence as possible to support the hypothesis. use of a variety of scientific equipment and record your data in an organized manner. Before conducting any experiment you should 13
be familiar with the equipment you will be using. (See section experiment is insufficient to prove much of anything. Whether“Laboratory Equipment.\") As you conduct laboratory activities in your hypothesis has been supported or refuted, further testing isthis course you will learn about how can be used. In order to make going to be an important part of the scientific process.sense of your results and show others what took place you willneed to record your data in an organized manner. (See sections ! If a hypothesis is supported repeatedly over time in various\"Making Data Tables and Graphs\" and \"Scientific Drawing.\") observations and experiments it can eventually be considered a theory. It takes quite a bit of time and experimentation for aAnalyze Your Data: hypothesis to reach this point it still has not been proven. If experimentation continues and a theory has been supported in any! After collecting data from experimentation, you will pull possible situation it can become a law. These facts of nature areeverything together and make sense of it all. What do the data undisputed in the scientific community and are now consideredmean? What is their significance? How do they relate to your proven. In physics and chemistry there are many ideas that havebackground research? Why did the results turn out the way they become laws such as Newton's laws of motion. In biology,did? Was anything surprising about what happened? Were there however, there are relatively few laws and more theories.any patterns that emerged? Were there any mistakes made in thedesign or conducting of the lab that could have caused errors in Reporting Results:the data? How might this research be continued?” ! Typically when you reach the end of an experiment, you areConclusion: not going to keep the information to yourself and will report your findings to the scientific community. In your report there is a! Ultimately you need to determine whether you accomplished written explanation of the experiment, results including datawhat you had set out to do. Sometimes there will only be general tables, graphs and drawings and conclusions so that otherobjectives that you were trying to meet. You should think about scientists can repeat the procedure, analyze their data and drawwhether or not you met those goals and specifically what you did their own conclusions. Reporting results helps to improve ourto reach them. For lab work that involved the development of a own scientific process and opens lines of communication to allowhypothesis, there are two possible outcomes. If the data do not our understanding of the natural world to grow. In the real worldseem to back up your initial prediction, we say that the hypothesis there is no end to the methods of science.has been refuted. This means we have to reject our hypothesis,modify it based on our new data and conduct the experimentagain. If the data back up the hypothesis, we say it has beensupported. In any of the work we will be doing in this course wewill never use say that we have proven anything. One little 14
SECTION 2Applying Methods of ScienceFigure 2.2 Paramecium caudatumParamecium caudatum inhabits aquatic ecosystems full of organic matter and remains active throughout the year, even when the water is very cold. Thephotograph was taken using 400x magnification. Source: http://www.flickr.com/photos/microagua/3221193288/! Paramecia are single-celled, microscopic organisms that live stimulus indicates a positive response; movement away from thein fresh water. Like other living things, paramecia respond to stimulus indicates a negative response.changes in their environment. For example, if a parameciumencounters an obstacle in its path, it will avoid it by swimming ! A student prepared several covered slides of paramecia inaway from or around the obstacle. fresh water. The student added different stimuli and observed the behavior of the organisms under a microscope. The diagrams! A paramecium may respond positively or negatively to a below show what the student observed.stimulus, or it may not respond at all. Movement toward the 15
Comparing the results: Questions: 1. Which situation number represents the normal conditions forIn the left column of the table below, identify the six differentstimuli. In the right column of the table, use “+” if the paramecia paramecia?moved toward the stimulus, “-“ if they moved away, and “0” for 2. What is this “normal” situation called and what purpose doesno response. observing the response to it serve in the experiment? STIMULUS RESPONSE (+, -, 0) 3. Which substance caused the strongest positive response by the1 02. 0.5% salt solution paramecia? Explain your reasoning.3 4. What type of data are collected in this experiment?4 5. Form a hypothesis about how a population of paramecia would56 respond to the addition of a drop of 10% salt solution. 6. Give reasons for the hypothesis you formed. 7. What are the subject, independent variable and dependent variable in your hypothesis? Adapted from BIOLOGY: The Dynamics of Life, 2000 16
CHAPTER 3Lab Products Source: http://www.flickr.com/photos/davidorban/4472746709/ 17
SECTION 1Lab ReportsFigure 3.1 Scientific JournalsSource: http://www.flickr.com/photos/kahunna/2728840649/ ! To facilitate this process and to keep you organized, you will make use of the Biology Lab Template to create your lab report in! Scientists will typically publish extensive, formal reports in the Pages app on your iPad. You will use this format with each labscientific journals to share their work, thought processes and we do to “publish” your experiment. Be sure to follow it closely.results with the world. While in this course we will notnecessarily be making any groundbreaking discoveries, it is stillimportant to be able to communicate the work we are doing, theresults we find and think about how this all relates to the topicswe have been covering. 18
General Rules: Background: • You may feel free to ask questions or use your textbook and Answering the background questions allows you to explain the notes for help. biological material learned in class or from research and observations that provide the basis for the experiment. Your • You may work with a partner to collect data or answer responses to these questions should be recorded in your own questions as directed, but you must submit your own data words, with complete sentences. tables, graphs and responses to questions in your own words. Hypothesis: or Objectives: • Proofread and spell-check your document before submission (spelling and grammar do count). Think of the significance of A hypothesis is a one or two sentence prediction of your expected an essay assignment for English or history. These have the results. Since it is a prediction of what is to come it should be same significance! written in the future tense. Do not begin with “I think”or “I believe,” simply state with confidence what is expected in the data. • Make statements with confidence and support your ideas with If you only have objectives, simply copy them word for word into examples. your report. Objectives are the intended goals of the lab. • Do not use any personal pronouns, such as: I, me, my, we, our, Examples: you, etc. Hypothesis: Earthworms left in constant darkness will require • Do not write out the questions. Instead, you must rephrase more food than those exposed to alternating light and darkness. them as a part of each response. Objective: Describe how the presence or absence of populations ofIn typing your report you must use the section headings that follow. aquatic invertebrates indicates water quality.Title: Results:Write a brief, original title, which includes the test subject and This section is for you to record what happened during the lab.describes the main concepts investigated in the lab. Typically, you Results can include data tables, graphs, drawings or writtenshould not simply use the title of the lab. descriptions. Data tables need to be created in the Pages app.Example:! The Effects of Temperature on Growth Rates of Invertebrates 19
Graphs will be created in the Numbers app and copied into your • Identify the sources of error that influenced the data. These arereport. (See instructions for making data tables and graphs in often things that should have been controlled variables but mayChapter 3, Section 3.) Drawings will be done in the Notability app not have been. Tell how the errors affect the results and whatand added to your report as a screenshot image. (See Chapter 3, things can be done differently to fix those errors. Explain at leastSection 2 for details on making scientific drawings.) three or four ideas.Analysis: • Describe how the concept of this lab could be explored further. You may look at some “spin-off” experiments that could studyIt is in this section that you pull together the results of your ideas related to what was learned in this lab.experimentation by showing that you understand the conceptsbehind your lab work. Detailed, thoughtful interpretation is Conclusion:expected. This is a brief section in which you restate the hypothesis andYour responses to all of the follow up questions should be written whether the data have supported or refuted it. Recap the resultswith complete sentences. For every statement you make, back it up briefly to support your claims. As always be sure to explain “how”with examples to show “how” or “why.” or “why.” If the lab had objectives rather than a hypothesis, indicate whether or not the objectives were met and discussThe questions at the end of each lab are often divided into different specifically what was done to meet them or why you think thesections that will require you to think about the lab and objectives were not accomplished.information in a variety of ways. Example:• Analysis questions are to explain the meaning or significance of the results. This is where you tell why the results happened the Conclusion: It had been predicted that three of four carbohydrate way they did. Relating the results to the background information tests would give a positive reaction and they did. The beef sample is important. You will also tell what was learned from the data was the only one to produce a negative test, therefore, the data including any patterns or surprises. supported the hypothesis.• Describe any techniques or skills that were learned or used for this lab (state several as applicable). Describe the way in which you utilized the required equipment, being sure to name the equipment / supplies / chemicals in your explanations. 20
SECTION 2Scientific DrawingFigure 3.2 Scientific drawing of a fishDrawing of a Pompano (Trachinotus sp.) created 5 Jul 1865 by Jacques Burkhardt at Rio de Janeiro, Brazil.Source: http://www.flickr.com/photos/66257786@N03/8426584363/! Drawing is a form of qualitative data that is an important observe details more closely and helps you create a mental picturepart of many lab exercises. In order for them to be of any real of what you have drawn.value they must be accurate, original (not copied) and representboth what you see and know. You do not have to be an artist to ! A good set of drawings will require a bit of planning. Studymake worthwhile drawings. Using drawings as you perform lab the positions and sizes of structures and think about how you willwork provides a number of important benefits. It forces you to represent them in your drawing. While a drawing alone is beneficial, it is almost worthless without labels, so always leave space to add notes afterward. When drawing on paper, use a ruler to 21
draw a straight line from the part of your drawing to the Common Mistakes to be Avoided While Drawing:appropriate label without crossing over other label lines. Printyour labels legibly, parallel to the top and bottom of the page. Some of these tips are more appropriate for drawing on paper, but they are Your labels should indicate what the important structures are still important to keep in mind.and / or significant information about details that cannot beshown in the drawing. 1. Fuzzy lines or overlapping of the ends of lines where one line joins another.! When making drawings in the laboratory for this course, youwill use the Notability app on your iPad. While not specifically a 2. Lines that are not uniform because of careless work.drawing app, you have the options of different widths and colorsfor both pens and highlighters. Used in combination, you can 3. Unnecessary lines or lines without meaning. Every line shouldeffectively create accurate representations of what you are seeing. be significant. Once you have created your drawings, take a screenshot and addit to the “Results” section of your lab report. Once added you 4. Labels irregularly printed or so large they obscure the drawing.must crop your image to remove anything that is not necessaryand enlarge your image to fill the space across the page. To crop 5. Label lines that are crossed, too long or are otherwise confusingan image, tap to select it then tap the paintbrush icon. Tap the to follow.“Image” tab and then “Edit Mask.” Use the blue dots to drag thesides inward until all unnecessary areas have been cut out, then 6. Drawings that are not good representations of the actualtap “Done.” structures. 7. Poor proportions of the various parts to each other and to the whole drawing. 22
SECTION 3Data Tables and GraphsFigure 3.3 DataTables and GraphsAnalyzing data that has been organized and visually represented in graphs. Source: http://www.flickr.com/photos/safari_vacation/8027644078/! Having your results well organized is important not only for Data Tables:you to be able to interpret and understand them, but also forothers to be able to clearly see what was done. The best way to do ! Placing data in a table allows you to be more organized sothis for quantitative data is with data tables and graphs. For this you can see your results clearly and then interpret them morecourse you will generate data tables and graphs using Microsoft easily. Each table must have a title explaining what the data itExcel. Once your data tables and graphs have been created, you contains are as well as rows and columns with labels identifyingcan simply copy and paste them into your lab report. what the information is in each. Part of that information must include the units used for whatever measurements have been 23
made. Typically the independent variable is listed in the first Graphs:column, while the dependent variable data is listed in the columnnext to it. ! After collecting numerical data in a table it is quite common to put the data into a graph. By creating graphs you to get a visual! Data tables can be easily created in the Pages app for lab representation of the data that allows you to actually see any patterns. Graphs can easily be created in the Numbers app andreports. To insert a data table, tap the plus menu icon , , and then copied and pasted into your lab report. The workspace in the Numbers app is divided into boxes called cells as seen below.the first chart option. By tapping on the or buttons at the Recreating a simplified version of your data table within thesecorners of the data table, you can change the number of rows or cells is how each graph is started. Double tap on a box that youcolumns. need to add information to or copy and paste your data from your table.! What follows is an example showing a class' results from anexperiment testing the effect of exercise on students' heart rates. Line Graph You will notice that there is a title explaining what the data in thetable are and there is a label for each column and row. ! A line graph is used to illustrate how two variables are related or how one variable changes because of the other. As you Effects of Exercise on Heart Rate create a line graph, the independent variable will appear on the horizontal or x-axis while the dependent variable will be on the Resting INDIVIDUAL CLASS AVERAGE vertical or y-axis. After Exercise HEART RATE (BEATS PER1 min after exercise (BEATS PER MINUTE) ! In the example that follows, a bird watching club has5 min after exercise observed and recorded the average number of birds that visit bird MINUTE) 72 feeders placed in the school's courtyard over a period of four 112 months. In addition to the total number, they have kept track of 73 90 how many of them were brown. 75 110 94 76Example taken from Glencoe Science’s Biology by Biggs, Alton et al. 2007 --Continued-- 24
Example taken from Glencoe Science’s Biology by Biggs, Alton et al. 2007 a. If the values for the X Axis are long, you should change the “Label Angle” to either “Left Diagonal” or “Left Vertical.”! Once the basic data table has been created you are ready togenerate the graph itself. 7. Tap “Y Axis,” turn the “Axis Name” switch on, then tap the paintbrush to close the menu.1. Start by tapping the top left box, then drag the blue dot to highlight the columns and rows that contain your labels and 8. Double tap “Title” in your graph to give it a descriptive title. data. Be careful not to highlight any columns or rows without Your title needs to include the subject, independent variable and data. Doing so will cause problems with the graph. dependent variable. Repeat the process for “Value Axis” and “Category Axis” to give them appropriate, descriptive labels.2. In the menu that appears, choose \"Create Chart\" to start creating the graph itself. ! Once your graph has been generated you can copy it into your lab report. Start by tapping the graph to select it. In the3. From the list of \"Charts\" choices select menu that appears, choose \"Copy.\" Go into your lab report document, touch and hold where you want your graph to go and4. To complete all the necessary details for your graph, tap the choose \"Paste.” paintbrush icon.5. Click the \"Chart\" button, then “Chart Options.” a. If you are creating a graph with only one line, slide the \"Legend\" switch to “OFF.” b. Tap “Chart Title” and move the switch on.6. Tap the back arrow twice, then select “X Axis” and turn the “Axis Name” switch on. 25
Column Graph 4. “To complete all the necessary details for your graph, tap the! Column graphs are used to compare data from different but paintbrush icon.related groups. The different groups or independent variable willappear on the x-axis while the dependent variable data still a. Click the \"Chart\" button, then “Chart Options.”appears on the y-axis. In this example scientists are comparing thenumber of times different insects flap their wings in one second. b. If you are creating a graph with only one bar per category, slide the \"Legend\" switch to “OFF.” Example taken from Glencoe Science's Biology by Biggs, Alton et al. 2007 5. Tap “Chart Title” and move the switch on.! Once you have recreated your data table in Numbers, theprocedure for making a column graph is very similar to that for a. Tap the back arrow twice, then select “X Axis” and turn thecreating a line graph. “Axis Name” switch on.1. Start by tapping the top left box, then drag the blue dot to 6. If the values for the X Axis are long, you should change the highlight the columns and rows that contain your labels and “Label Angle” to either “Left Diagonal” or “Left Vertical.” data. Be careful not to highlight any columns or rows without data. Doing so will cause problems with the graph. 7. Tap “Y Axis,” turn the “Axis Name” switch on, then tap the2. In the menu that appears, choose \"Create Chart\" to start creating paintbrush to close the menu. the graph itself.3. From the list of \"Charts\" choices select the first graph option 8. Double tap “Title” in your graph to give it a descriptive title. with vertical bars. Your title needs to include the subject, independent variable and dependent variable. Repeat the process for “Value Axis” and “Category Axis” to give them appropriate labels. 9. Once your graph has been generated you can copy it into your lab report. Start by tapping the graph to select it. In the menu that appears, choose \"Copy.\" Go into your lab report document, touch and hold where you want your graph to go and choose \"Paste.” --Continued-- 26
! Once you have recreated your data table in Numbers, the procedure for making a pie graph is very similar to that for creating a line or column graph. ! After highlighting your data columns, you will choose the pie graph image. Tap the paintbrush and choose “Chart Options.” Follow steps 4-8 under “Line Graph” to add the necessary details to your graph.Pie Graph! A pie graph is used to show how different parts add up toequal the whole of something. It is unique in that a pie graph doesnot use axes like line and column graphs, but rather shows theparts as different sized slices of a circle. In this example a studentis showing how much time she spends doing various activitiesduring a typical weekday. Example taken from Biology: The Study of Lifeby Schraer, William D. and Herbert J. Stoltze 1999 27
CHAPTER 4Laboratory Equipment Source: https://pixabay.com/en/lab-research-chemistry-test-217040/ 28
The following pages will identify some of the common pieces oflaboratory equipment that you will use in this and future classes.The use of the equipment will be covered in the lab exercises. Referto these pages when preparing for a lab so you will be familiarwith the equipment you will be using. Droppers! ! ! ! RulerGeneral Equipment !! ! Safety Equipment ! Beaker!! ! ! Graduated Cylinder Safety Goggles ! ! Vinyl Apron! ! ! Latex GlovesTest Tubes and Rack! ! Petri Dish 29
Microscope Equipment Dissection Equipment Dissection Tray !Compound Light Microscope ! Dissection Probe!! ! Dissection ScissorsGlass Microscope Slide! Plastic Coverslips ! ! ! ! Forceps! ! ! ! ! ! Dissection Pins 30
CHAPTER 5Semester 1 Lab Work These are cheek cells stained with methylene blue. (400x) Source: http://www.flickr.com/photos/40964293@N07/3895511548/ 31
SECTION 1Dependent & Independent VariablesFigure 5.1 European corn borer, Ostrinia nubilalisEuropean corn borer larva, Ostrinia nubilalis Photo by Keith Weller. Source: http://commons.wikimedia.org/wiki/File:Corn_borer.jpg! In this exploration, you will model a controlled experiment ! The amount of corn produced in a field is called its yield.to test the effect of different levels of European Corn Borer (ECB) The number of kernels on an ear determines the yield. A highinfestation on the yields of two different varieties of corn. The yield results from many kernels on every ear and many ears in alevel of ECB infestation is the independent variable that affects field. A corn plant normally produces one ear per plant. Manythe outcome of the experiment. All other conditions necessary for problems, including insects, plant diseases, extreme weathercorn plant growth, such as soil and nutrient conditions, watering conditions, or poor soil conditions can cause low yields. Inamounts, and light conditions, are constants that remain the same. current agricultural practices, corn plants have been selectively bred and genetically engineered to resist insect pests. 32
Tap the following link to open it in Safari. Then copy & paste it types of corn. The seeds will be planted in all three pots andin the Puffin Web Browser app. Finally, tap the “Theater” button each growth chamber will automatically be labeled. at the top left of the screen or find it in the menu . 4. Drag a level of ECB infestation to each set of plants in the growth chambers. You may choose to have no infestation, a lowhttp://goo.gl/aPS2l level of infestation, or a high level of infestation for each growth chamber. The selection will be applied to each plant and theBackground: Answer all of these questions in your own words with label will be updated with the information of the level of ECBcomplete sentences in your lab report by reading the \"Greenhouse treatment.Handbook\" in the virtual lab. 5. Tap the \"Grow\" button found near the base of the growth1. Summarize the life cycle of a corn plant. chambers. The corn plants will grow for 140 days (about 4.5 months).2. Identify what type of insect the adult European Corn Borer is. 6. Drag each ear of corn from the plants to the weighing dishes3. Describe why the ECB larva are such a problem for corn plants? below each plant to remove the kernels so the yield from each plant can be determined.4. Describe what makes the Bt corn different from a typical corn plant? 7. Drag each of the three weighing dishes for one chamber to the balance then determine the average yield for the growth5. Identify a problem that may result from the use of Bt corn. chamber. Round the average mass to the tenths place when you record your data. Then tap the \"Reset\" button.Hypothesis: Write a hypothesis predicting which type of corn (BTcorn or non-BT corn) will have greater kernel production as the 8. Repeat the experiment for the both types of corn (Super Harvestamount of ECB infestation increases. and BT123) until you have tested them under all three ECB infestation levels.Procedure: --Continued--1. Recreate the data table from the “Results” section on the next page in your lab report.2. You will grow Super Harvest (non-BT) and BT123 corn to observe their growth of under different levels of ECB infestation.3. Drag Super Harvest or BT123 seed varieties to each of the two planter chambers. You may choose to plant one or two different 33
Results: Recreate this data table in your lab report. 2. Identify at least three constants that would have been present when growing the corn plants. SUPER HARVEST BT 123 CORN (g) 3. Evaluate whether or not this lab procedure meets the definition of being a controlled experiment? Explain why or why not? (It CORN (g) has nothing to do with it being on a computer) No ECB Infestation 4. Having completed this one experiment, separate from what is Low ECB Infestation accomplished by the lab report, determine what the next step in High ECB Infestation the scientific process should be. Explain why.Create a column graph of your data in Numbers, then add it to the Spin-off:“Results” section of your lab report following your data table. 1. Based on the data, infer whether a farmer would gain or lose Refer to the instructions in Chapter 3, Section 3. financially by planting Bt corn if there were no ECB infestationAnswer all of the following questions in your own words with complete in a certain year.sentences. Make separate headings for the different sections. 2. Infer what might happen to the natural environment if Bt corn affects non-target organisms such as beneficial insects orAnalysis: harmless insects. 3. Propose a solution for what might need to be done if ECB1. Look at your graph to summarize how the Super Harvest and becomes resistant to Bt corn. BT 123 crops were affected as the ECB infestation increased. Conclusion: Decide whether the results supported or refuted the2. Look at your graph to evaluate whether or not the Super hypothesis. Explain using evidence from the results. Harvest and BT 123 corn varieties were equally effective at controlling the ECB. Use the data in the data table to describe Adapted from Glencoe Science’s Biology by Biggs, Alton et al. 2007 how this is shown.Techniques:1. Determine what the subject, the independent variable and the dependent variable were in this experiment. 34
SECTION 2Photosynthesis Virtual Lab! Photosynthesis is the process by which some autotrophs are absorbed or reflected by substances called pigments, includingable to produce sugars from carbon dioxide and water, using chlorophyll, which appears green.energy from the sun. In plants, photosynthesis mostly takes placein the leaves. Water is absorbed by the roots and transported up ! In this exploration you will perform an experiment tothrough the plant to the leaves. Carbon dioxide enters the under investigate what colors of light cause the most photosynthesisside of leaves through small pores called stomata. Sunlight is the and, as a result, the most plant growth. You will then comparenatural energy source for photosynthesis. Light can be either plant growth measurements and interpret a graph. 35
Tap the following link to open it in Safari: https://goo.gl/8SnCK8 4. Select a color of light to shine on the seeds while they grow to see the results.Background: Use the information on the previous page and the“Introduction” video in the virtual lab to answer the following questions 5. Measure the height of each of the three plants. Record thein your own words, with complete sentences in your lab report. average height in your data table.1. Briefly describe the process of photosynthesis? 6. Select another color of light until you have tested all colors on that type of plant.2. What is the white light from the sun made up of? 7. Repeat the process for the other two types of plants until your3. What happens when the sun's white light passes through a data table is complete. prism? 8. Create a column graph using the Numbers app showing the4. Describe why plant leaves appear green. average height of each type of plant observed after 30 days of growth under each color of light.5. What within a plant causes the green appearance?Hypothesis: Write a hypothesis predicting which color in the Results: Recreate this data table in your lab report.visible spectrum will cause the most plant growth and which colorin the visible spectrum will cause the least plant growth. LIGHT SPINACH RADISH LETTUCE COLOR AVERAGE AVERAGE AVERAGEMethods: HEIGHT (cm) HEIGHT (cm) HEIGHT (cm)1. Recreate the data table at right into the “Results” section of your Red Orange lab report. Green2. Select “Experiment” in the Photosynthesis app to start setting up Blue your experiment. Violet3. Select which type of seed you will plant first. --Continued-- 36
Answer all of the following questions in your own words with completesentences in your lab report. Make separate headings for the differentsections.Analysis:1. Describe the differences and similarities observed in the growth of the different types of seeds under the different colors of light. (Refer to your graph to help answer.)2. Identify which color in the visible spectrum caused the most plant growth?Spin-off:1. Given that white light contains all colors of the spectrum, decide what growth results would be expected under white light? Explain.Techniques:1. Identify three of the constants in the experiment.2. Identify the independent variable.Conclusion: Decide whether the results supported or refuted thehypothesis. Explain using evidence from the results. Adapted from Glencoe Science's Biology: The Dynamics of Life by Biggs, Alton et al. 2004 37
SECTION 3You Want Me To Eat What?Figure 5.2 Variety of food itemsSource: http://commons.wikimedia.org/wiki/File:Good_Food_In_Dishes_-_NCI_Visuals_Online.jpg! Different cultures around the world have developed an ! In this activity, you will identify some of the components ofassortment of diets that reflect their agricultural conditions, food that are required to sustain life. These components that makecustoms, and tastes. As different as they may seem at first glance, up food are called nutrients. A nutrient is considered essentialmost of these diets supply the same nutritional requirements when it cannot be synthesized within the organism but must beneeded by humans to sustain life. What are these nutritional obtained by the organism from its environment.requirements? How can such different food sources as beef, rice,beans, insects, and vegetables all supply them? ! You will be using indicators as chemical detection tools to find out what nutrients are present in foods. Indicators are 38
chemical compounds used to detect the presence of other Background: Read the entire laboratory procedure carefully, and recordcompounds. Detection is based on observing a chemical change your responses to the following questions in your own words withthat is taking place between the indicator and the other chemical complete sentences in your lab report.compound. Most often, this is a change in color. 1. Identify the scientific problem that will be able to be answeredMaterials: iodine! ! ! Benedict’s solution by this laboratory procedure.safety goggles! ! distilled water! ! Biuret solutiongloves! ! ! masking tape! ! droppers 2. When at home, how can the general public know whichapron! ! ! Sharpie® marker! mortar and pestle nutrients are found in the foods that they eat?15 test tubes! ! beaker (400 mL)! hot platetest tube clamp! ! 3 food samples! ! water 3. Identify the general purpose of indicators.test tube rack! ! 4. Describe what happens when an indicator has worked.Safety Notes: 5. Identify the three nutrients that will be tested for in this• Biuret solution can burn your skin. Iodine and Benedict’s experiment. solutions are toxic. If any of these solutions come in contact with skin or clothing, rinse thoroughly with water. 6. Describe what is done to prepare the food samples before the experiment. Infer why this is done.• Hot plates and boiling water can cause burns. Handle the test tube clamp carefully to avoid dropping the test tube or splashing 7. Identify what is in each of the negative control test tubes when the water the indicators are added during the experiment? 8. Identify what is in each of the positive control test tubes when the indicators are added during the experiment? Procedure: 1. List the three foods you will be testing in the “Hypothesis” section of your lab report. Predict and record which of the nutrients you will be looking for (background question 5) will be present in each food sample you are about to test. 2. Record the name of each sample in the “Results” section of your lab report. Assign each sample a number from 1 through 3. 39
3. Download the “What Am I Eating Data Table” file found here Figure 5.3 (https://goo.gl/it6Gtb) and open it in the Notability app. Indicate the color results that appear in each of the test tubes 9. Add 15 drops of your second food sample to each of the 3 test after adding the indicators. tubes in the third column.4. Each of the food samples you will be testing has been prepared 10.Add 15 drops of your third food sample to each of the 3 test by being mashed and mixed with a small amount of water. tubes in the fourth column.5. Arrange your fifteen test tubes in the racks in three rows of five 11.Add 15 drops of sugar solution to the “+ sugar” test tube in the tubes each as shown in Figure 5.3 to the right. fifth column.6. With a Sharpie® and masking tape, you will add a label near the 12.Add 15 drops of starch solution to the “+ starch” test tube in the top of all 20 test tubes as follows: fifth column. a. Label the 3 tubes in the first column as follows: “- sugar”, 13.Add 15 drops of protein solution to the “+ protein” test tube in “- starch”, “- protein”. These are your negative controls. the fifth column. b. Label the 3 tubes in the second column as follows: “1/sugar”, 14.Because you know what nutrient each solution composed of, “1/starch”, “1/protein”. these controls can be used to determine what a positive test for each indicator looks like. Color changes in indicator testing are c. Label the 3 tubes in the third column as follows: “2/sugar”, not always obvious. So it is important to become familiar with “2/starch”, “2/protein”. exactly what a positive test looks like. In that way, you can be d. Label the 3 tubes in the fourth column as follows: “3/sugar”, “3/starch”, “3/protein”. e. Label the 3 tubes in the fifth column as follows: “+ sugar”, “+ starch”, “+ protein”. These are your positive controls.7. Add 15 drops of water to each of the 3 negative control test tubes in the first column.8. Add 15 drops of your first food sample to each of the 3 test tubes in the second column. 40
informed and experienced when you begin testing the food 17.Protein test:samples. • Add 15 drops of Biuret solution to each of the 5 test tubes15. Sugar test: THESE ARE THE ONLY TUBES YOU HEAT! labeled “protein.” After adding the indicator, gently shake each test tube side to side to make sure everything is wella. Add 15 drops of Benedict’s solution to each of the 5 tubes mixed. labeled “sugar.” Benedict’s indicates the presence of sugars (or simple carbohydrates). When you add your indicator to 18. Remove the five test tubes for each nutrient from the rack. Hold each tube, be careful not to touch the side of the test tube with them in front of a piece of white paper to clearly see the colors. the dropper. Hold the dropper over the tube mouth and let Make sure the test tube labels are visible and take a picture. the drops “free fall” into the Recreate the colors in the appropriate spaces of your data table tube. After adding the indicator, in the Notability app. Once complete, take a screenshot of your gently shake each test tube side data table and add it to the results section of your lab report. to side to make sure everything is well mixed. Answer all of the following questions in your own words with complete sentences in your lab report. Make separate headings for the differentb. Heat the tubes in a boiling water Figure 5.4 sections. bath for 5 minutes without disturbing. (You may continue Analysis: with the other tests while waiting for this test.) Use a test- 1. Compare the results of the indicators in each food sample to the tube clamp to lift the test tubes positive and negative controls. Decide which nutrient(s) were in out of the boiling water bath in more food samples than the other nutrients order to examine the contents (see Figure 5.4 to the right). Techniques:16. Starch test: 1. Describe why a negative control and a positive control were needed for each test. (Think about what was in each of the control • Add 15 drops of iodine to each of the 5 test tubes labeled test tubes when the indicator was added to in each one.) “starch.” After adding the indicator, gently shake each test tube side to side to make sure everything is well mixed. --Continued-- 41
2. Identify the type of data collected during this experiment. Conclusion: Compare the results of the indicators in each food Describe what makes it fit this category of data. sample to the positive and negative controls. Decide which of the nutrient predictions from each of the hypotheses were supportedErrors: and which were refuted. Be sure to explain.1. Identify a possible source of error from the experiment. Positive controls showing each indicator’s reaction to starch, sugar and protein. Describe how it would have affected the results. Adapted from Kendall / Hunt's Insights in Biology 2nd Edition 20072. If only one dropper were used for all of the indicators, explain why would it be important to rinse the dropper between tests?Spin-off:1. Identify two other nutrients that might be might be worth testing for. Explain why it would be good to test for these nutrients.2. Create a table listing the six types of nutrients across the top. List the all of the specific foods you ate yesterday along the left side of the table. Decide which nutrient(s) you received from each of the foods you ate and place an “X” in the appropriate column. You can record what nutrients you think the food contains or you can do a quick search online. 3. Based on the data table you created for the previous question, explain what, if anything, surprises you about your diet.4. Explain whether or not your diet adequately meets your nutritional requirements.5. Explain whether or not you take particular care about what you eat each day. Are there certain kinds of food that you try to eat or try to avoid? 42
CHAPTER 6Semester 2 Lab Work Source: https://en.m.wikipedia.org/wiki/File:DNA_Double_Helix.png 43
SECTION 1Normal & Plasmolyzed CellsFigure 6.1 Elodea leaf cellsImage of Elodea leaf cells taken through a microscope. Photo by Brandon Zierer. Source: http://www.flickr.com/photos/arwing3/6946034795/! Diffusion of water molecules across a cell’s plasma Plasmolysis may lead to the death of the cell. Most cells live in anmembrane from an area of high water concentration to an area of environment where movement of water in and out of the cell islow water concentration is called osmosis. This movement of about equal. Therefore, there are no harmful effects to the cell.water may be harmful to cells. If too much water is lost from thecell, the plasma membrane and the cell contents shrink. This is ! The purpose of this investigation is to observe the effects ofcalled plasmolysis. In an animal cell, the entire cell shrivels. In a plasmolysis in Elodea cells and to measure the rate of plasmolysisplant cell, the cytoplasm shrinks away from the cell wall. in potato slices. 44
Materials: Results: Recreate this data table in your lab report.3, 250 mL beakers!coverslip! ! ! ! microscope! ! microscope slide SOLUTIONS MASS MASS AMOUNT PERCENT15% salt solution! ! distilled water! ! 5% salt solution BEFORE (G) AFTER (G) CHANGE (G) CHANGEElodea plant ! droppers! ! ! 10 potato slicesBackground: Answer the following questions in your own words with Distilledcomplete sentences. Water1. Which cell organelle determines what can enter or exit the cell? 5% Salt Solution2. What are the two general types of transport moving materials in 15% Salt or out of a cell? Solution3. What is osmosis? Methods:4. Describe what happens to a plant cell in each of the following Part A – Potato plasmolysis environments: isotonic; hypotonic; hypertonic. 1. Recreate the data table shown above in your lab report.5. What is plasmolysis? 2. Label the three beakers “Distilled,” “5%,” and “15%” by writingHypotheses: After reading through the whole lab, write your three on a paper towel placed under the beakers.hypotheses. 3. Obtain ten, approximately 1 cm thick, potato slices.1. Write a hypothesis that predicts what is expected to happen to the mass for each of the stacks of potatoes after they soak in each 4. Set aside one potato slice to compare flexibility at the end. solution. 5. Using paper towel, gently pat the slices dry to remove any2. Write a hypothesis that predicts what is expected to happen to excess moisture from the surface. Then use the balance to find the flexibility of the potatoes in each stack after they soak in each the mass of three potato slices, record the data in the first solution. column of your data table then place the slices in the “Distilled” beaker. Repeat two more times for the “5%” and “15%” beakers.3. Write a hypothesis predicting what is expected to happen to the Be careful not to switch potatoes between beakers. cell membrane and organelles in the Elodea leaf after soaking in the 15% salt solution. --Continued-- 45
6. Add just enough distilled water to the appropriate beaker to Part B – Elodea plasmolysis cover but not float the slices. 1. Import the file “Elodea Drawings” into Notability from Power7. Add just enough 5% salt solution to the appropriate beaker to School. Label one circle “Normal Cell” and indicate the total cover but not float the slices. magnification and what solution it is in. Label the other circle “Plasmolyzed Cell” and indicate the total magnification and8. Add just enough 15% salt solution to the appropriate beaker to what solution it is in. cover but not float the slices. 2. Prepare a wet mount slide of an Elodea leaf using tap water.9. Set the three beakers aside allowing the potatoes to react for twenty minutes, then go to Part B. 3. Locate the cells on low power, then, work up to high power.10.After twenty minutes, remove the potato slices from the 4. Closely observe the location of the organelles and plasma beakers. Quickly blot the excess water from the surface with a membrane then as carefully and accurately as possible, draw paper towel and find the new mass of each stack. Record these only one or two cells in your circle marked “Normal Cell”. new masses in the second column of your data table. (Refer to the scientific drawing tips in Chapter 3, Section 2.) Label parts of the cell that you observed in your drawing.11.Record a brief description of the potato slice flexibility in the “Results” section of your lab report by comparing to the once 5. Remove the slide from the microscope. Take off the coverslip slice that you set aside. and gently blot the leaf with some paper towel. Using a dropper, add several drops of 15% salt solution to the leaf and replace the12.Calculate the amount of mass change (Mass After – Mass Before = coverslip. Set the slide aside to adjust for three minutes. Amount Change) for each stack and record this difference in the third column of the data table. If there is a decrease in mass you 6. After three minutes, locate the cells again under low power, will end up with a negative number. then, work up to high power.13.Calculate the percent change for each stack using the following 7. Closely observe the location of the organelles and plasma formula: membrane then carefully and accurately diagram only one or two cells in the space provided in your circle marked Amount Change “Plasmolyzed Cell”. Label parts of the cell that you observed in X! 100! =! Percent Change your drawing.! Mass Before! --Continued--14.Construct a column graph using the Numbers app showing the percent mass change of the potatoes in the three solutions. (See graphing instructions in Chapter 3, Section 3.) 46
8. Take a screenshot of your Elodea drawings, crop it and add it to Spin-off: the “Results” section of your lab report. 1. Describe what would happen to the cells of a person’s digestive9. Following the procedure in step 5, replace the salt solution with tract if they were to drink salt water while stranded at sea. distilled water. Explain why this would happen.10.Relocate the cells on low power, then, work up to high power Techniques: (Include specific, scientific terms to answer these questions.) and write a description of how the appearance of the cells changed in your lab report in the space following your 1. What role does finding the mass of the potatoes at the beginning drawings. and drawing the normal Elodea cells serve in the experiment?Answer all of the following questions in your own words with complete 2. Recording observations of cells shrinking as a result of watersentences. Make separate headings for the different sections loss or describing flexibility is what kind of experimental data?Analysis: 3. Recording measurements of water loss or gain is what kind of experimental data?1. Describe what happened to each stack of potato slices in terms of both mass and flexibility in each of the three solutions. Conclusion: Decide whether the results supported or refuted the Explain why these changes happened in each set. hypothesis. Explain using evidence from the results.2. Infer what might happen to the mass and flexibility of each set Epilogue: of potato slices if the time they were submerged was lengthened? During the lab it may have been difficult to see what happened to the Elodea cells when they were placed in the 15% salt solution and later in3. Describe the appearance of the normal Elodea cells in terms of the deionized water, or it simply did not happen the way that it should shapes, colors and position of specific organelles observed. have. To help you better understand what actually should have occurred, click the links below to view a short video showing actual Elodea cells4. Describe what happened to the cell membrane and internal being exposed to the same conditions as they were in the lab. organelles of the leaf cells when salt solution was added to the Elodea wet mount. Explain why these changes happened. • Elodea in 15% salt solution • Elodea in distilled water5. When the salt solution was replaced by distilled water in the Elodea wet mount, did the cells recover? Explain why. If Adapted from: nothing happened, explain what should have happened. • Hummer, Paul J., Probing Levels of Life – A Laboratory Manual, Merrill Publishing Co., 1986 • Biggs, Alton, et. al., Biology: The Dynamics of Life – Laboratory Manual, McGraw-Hill Companies, Inc., 2000 47
SECTION 2Cell Reproduction Virtual LabFigure 6.2 Cell DividingAnimal cell in anaphase of mitosis. Sister chromatids have just been pulled apart. Source: http://www.flickr.com/photos/carolinabio/6141866930/in/photostream/! Mitosis is the process by which most eukaryotic cells mitosis and create cells more often without allowing them thereproduce. This process is important not only for asexual chance to grow or carry out functions, as they should. Thisreproduction in many organisms but it is how growth occurs in condition is referred as cancer.multicellular organisms. Typically this is a carefully controlledprocess and accounts for a relatively small portion of a cell's ! In this virtual lab investigation you will answer the questionactivities. On occasion, however, natural errors within the DNA \"How can cancer cells be recognized?\" You will identify theor environmental factors can cause cells to lose control over various phases of the cell cycle and the compare and contrast the cell cycles of normal and cancer cells. 48
Tap the following link to open it in Safari. Then copy & paste it Hypothesis: Write a hypothesis in your lab report predicting whetherin the Puffin Web Browser app. Finally, tap the “Theater” button the normal or cancerous tissues will have a greater number of cells in mitosis. at the top left of the screen or find it in the menu .http://goo.gl/sUFNC7 Methods:Background: Write your responses to the following questions in the Part A – Cell Micro-Photographs“Background” section of your lab report in your own words withcomplete sentences. You can click on the TV or \"Information\" button in 1. On the biology laboratory home screen, tap the projector to viewthe virtual lab for help. micro-photographs of actual lung tissues.1. Describe the cell cycle.2. Identify the part of the cell cycle when a cell is growing and 2. Drag the normal lung tissue image to the projector. Repeat for the cancerous lung tissue image. carrying out normal functions.3. Identify the two parts of the cell cycle when is a cell dividing. 3. Record the differences you observe in the size and shape of just4. Identify the four phases of mitosis. the normal lung cells compared to cancerous lung cells in the5. Explain why chromosomes cannot be seen during interphase. “Results” section of your lab report. DO NOT TALK ABOUT6. Identify what happens to the nucleus during prophase. THE COLOR OF THE CELLS!7. Identify what happens to sister chromatids during anaphase.8. Identify what is it called when cells lose control of the cell cycle. 4. Click the \"Return\" button to return to the biology laboratory9. Explain why is it difficult for scientists to determine the exact home screen. causes of cancer. Part B – Microscope slides10.Identify one risk factor that may cause each of the following 1. Recreate the data table shown on the next page in the “Results” types of cancer: lung; ovarian; stomach. section of your lab report. 2. Tap the microscope to see microscopic views of prepared tissue samples. 3. Tap a picture on the Table of Contents to get information about one of the five cell phases. Use the forward and back pointers to move between phases. 49
4. Compare the normal lung tissue cells shown through the 8. Once you have examined all six tissue samples you will need to microscope with the cell phase pictures on the information calculate and record the percentage of cells dividing (cells in cards. Label the cells with empty boxes below them by dragging mitosis) for each one. Round to the nearest whole number. the corresponding label from the top of the information card. 9. Create a column graph with the Numbers app showing the5. After labeling all five cells, tap the \"Check\" button to verify your percentage of cells dividing for each of the tissue samples. answers. If any need to be fixed they will be surrounded with a Instructions for making a graph are available in Chapter 3, red box. Section 3.6. After you have correctly labeled the five cells, labels will appear Answer all of the following questions in your own words with complete below the other cells in the microscopic view. Count the number sentences. Make separate headings for the different sections. of cells in each phase and record the data in the table. Techniques: (Include specific, scientific terms to answer these questions.)7. Examine the other tissues by touching and holding the \"Tissue Slides\" box and selecting a new tissue sample. Repeat the 1. Identify the independent variable and dependent variable from labeling, checking and recording procedures for each of these this laboratory experience. tissues. --Continued-- INTERPHASE PROPHASE METAPHASE ANAPHASE TELOPHASE % CELLS 50 DIVIDING Normal Lung Cancerous Lung Normal StomachCancerous Stomach Normal Ovary Cancerous Ovary
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