What do cork and onion cells have in common

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Rutgers University – Newark

College of Arts & Sciences Department of Biological Sciences

General Biology II (21:120:102)

Lab Learning Objectives & Lab Learning Activities

CONTENT

General Information .................................................................................................... 3 1

Laboratory Safety Rules ............................................................................................... 4 2

Laboratory Syllabus ..................................................................................................... 5 3

Microscope Use ........................................................................................................... 7 4

4.1 The Compound Microscope ................................................................................. 7

4.2 The Dissecting Microscope ................................................................................... 9

Lab Report Format ..................................................................................................... 11 5

Lab 1 – Viewing and Measuring Cells ........................................................................ 12 6

6.1 Exercise 1 - Features of the compound microscope .......................................... 12

6.2 Exercise 2 – Procedure for viewing specimens .................................................. 14

6.3 Exercise 3 – The image under a compound microscope.................................... 15

6.4 Exercise 4 – Mirror images ................................................................................. 16

6.5 Exercise 5 – Features of the dissecting microscope .......................................... 17

6.6 Exercise 6 – Use of the dissecting microscope................................................... 18

6.7 Exercise 7 – Calculating total magnification of objects ..................................... 19

6.8 Exercise 8 – Determining the diameter of the field of view. ............................. 20

6.9 Exercise 9 – Using the diameter of the field of view to measure cells .............. 21

6.10 Exercise 10 – Preparing a wet mount of a naturally pigmented (red onion) cell.23

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6.11 Exercise 11 – Staining a wet mount of an unpigmented (human cheek) cell. ... 24

6.12 Exercise 12 – Estimating the size of a unicellular organism............................... 26

Lab 2 – Enzymes and Cell Function ............................................................................ 28 7

7.1 Exercise 1 – Browning of fruit ............................................................................ 31

7.2 Exercise 2 – Effect of temperature on enzyme-catalyzed reactions ................. 36

7.3 Exercise 3 – Effects of pH on enzyme-catalyzed reactions ................................ 39

Lab 3 – Cell Membranes and Water Balance ............................................................ 44 8

8.1 Exercise 1 – Movement of water into a "model cell" ........................................ 47

8.2 Exercise 2 – Using the plasmolysis threshold to estimate the concentration of solutes and water inside living cells .............................................................................. 52

8.3 Exercise 3 – Comparing solute concentrations (isotonic points) inside plant cells from different environments ........................................................................................ 56

Lab 4 – Photosynthesis .............................................................................................. 61 9

9.1 Exercise 1 – Separation of leaf pigments by paper chromatography ................ 62

9.2 Exercise 2 – Internal features of a leaf ............................................................... 64

9.3 Exercise 3 – Stomata .......................................................................................... 66

9.4 Exercise 4 – The effect of carbon dioxide and pH on the rate of photosynthesis68

9.5 Exercise 5 – The effect of the color of light on the rate of photosynthesis ....... 71

Lab 5 – DNA Fingerprinting ........................................................................................ 74 10

10.1 Exercise 1 – extraction DNA from cells .............................................................. 75

10.2 Exercise 2 – Practice using pipettes to load wells .............................................. 77

10.3 Exercise 3 – DNA fingerprints of unknown DNA samples .................................. 78

Copyright: Dr. Douglas Morrison Modified by Dr. Rola Bekdash Updated - January 2019

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General Information 1

 Course Coordinator: Rola Bekdash (rbekdash@newark.rutgers.edu); Boyden Hall 313; Extension 1267)

 Laboratory Supervisor: Sahil Wadhwa (swadhwa@scarletmail.rutgers.edu); Biology Learning Center, Boyden Hall 217; Extension 5108)

 Laboratory Supervisor Specialist: Albert Le Goff (alegoff@newark.rutgers.edu); Boyden Hall 111; Extension 1220)

Teaching Assistants

 TBD Location of the General Biology Laboratory: Boyden Hall 223A & 223B

Weekly Laboratory Sessions

Please attend the Lab session that you did register for. The duration of each lab session is 3 hours.

Section 1 Monday 1 – 3:50 pm

Section 2 Monday 1 – 3:50 pm

Section 3 Tuesday 8:30 – 11:20 am

Section 4 Tuesday 8:30 – 11:20 am

Section 5 Tuesday 2:30 – 5:20 pm

Section 6 Tuesday 2:30 – 5:20 pm

Section 7 Wednesday 8:30 – 11:20 am

Section 8 Wednesday 8:30 – 11:20 am

Section 9 Wednesday 11:30 am – 2:20 pm

Section 10 Wednesday 11:30 am – 2:20 pm

Section 11 Thursday 8:30 – 11:20 am

Section 12 Thursday 8:30 – 11:20 am

Section 13 Thursday 1 – 3:50 pm

Section 14 Thursday 1 – 3:50 pm

mailto:rbekdash@newark.rutgers.edu

mailto:swadhwa@scarletmail.rutgers.edu

mailto:alegoff@newark.rutgers.edu

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Laboratory Safety Rules 2

1. Wear your white lab coat before starting your lab session and bring your dissection kit with you.

2. Do not start any procedure until your Teaching Assistant (TA) has described and discussed the exercise and the potential hazards associated with it.

3. Wear protective eye wear for all dissection exercises as well as exercises using hazardous

materials. All students are required to get their own safety goggles to lab EACH day whether or not they are needed for the procedure.

4. Wear disposable gloves when you are doing dissection, working with preserved specimens, handling blood smaples or working with chemicals.

5. Keep long hair tied back if you are working with dissection specimens or other hazardous

material.

6. Do not eat or drink or bring any food or beverages into the lab. 7. Notify your TA and the lab supervisor of any accidents, including minor cuts, punctures, or

spill of chemicals. 8. If you have any medical condition (e.g. allergies, medication, and pregnancy) that may

increase your sensitivity to certain chemicals or procedures, you should notify your TA and consult your physician.

9. Dispose all sharps such as needles, razor blades, syringes, slides, Pasteur pipettes and capillary tubes in the “sharp containers”.

10. Dispose all live specimens and used gloves in the the container that has an autoclave bag.

11. Clean your work area with disinfectant at the end of each lab session and return all chairs to their designated places.

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Laboratory Syllabus 3

WEEK *LABORATORY TOPIC/QUIZZES *REVIEW & LAB PREPS

Week 1 1/22 – 1/24

No Labs this week

Week 2 1/28 – 1/31

Lab # 1 – Cells

Week 3 2/4 - 2/7

Review Lab # 1 Quiz 1 on Lab #1

Prep Lab # 2

Week 4 2/11 - 2/14

Lab # 2 – Enzymes

Week 5 2/18 - 2/21

Review Lab # 2 Quiz 2 on Lab #2 Finish Lab#2 Report

Prep Lab # 3

Week 6 2/25 - 2/28

Lab # 3 – Membranes

Week 7 3/4 - 3/7

Review Lab # 3 Quiz 3 on Lab #3 Finish Lab#3 Report

Prep Lab # 4 & Review Lab Exam I

Week 8 3/11 - 3/14

Lab Exam I (Labs # 1, 2 & 3)

Week 9 3/18 - 3/21

Spring Recess – No Labs this week

Week 10 3/25 - 3/28

Lab # 4 – Photosynthesis

Week 11 4/1 – 4/4

Review Lab # 4 Quiz 4 on Lab #4

Prep Lab # 5

Week 12 4/8 - 4/11

Lab # 5 – DNA Technology

Week 13 4/15 – 4/18

Review Lab # 5 Quiz 5 on Lab #5

Review Lab Exam II

Week 14 4/22 – 4/25

Lab Exam II (Labs # 4 & 5)

(*) PLEASE READ THE LABORATORY TOPIC BEFORE COMING TO CLASS

YOU ARE REQUIRED TO BRING A DISSECTION KIT YOU ARE REQUIRED TO ATTEND AND PARTICIPATE IN ALL THESE LAB SESSIONS. IF YOU MISS MORE THAN TWO LAB SESSIONS, YOU WILL BE ASKED TO WITHDRAW FROM THE COURSE. YOU CANNOT MAKE-UP FOR ANY MISSED LAB SESSION. IT IS YOUR RESPONSIBILITY TO KNOW WHAT YOU MISSED AND COVER IT. MAKE-UP FOR LAB QUIZZES MAY BE DONE WITH THE APPROVAL OF YOUR TA/PTL WITH THE SUBMISSION OF VALID DOCUMENTATIONS.

*NO MAKE-UPS FOR LAB EXAMS. A MISSED LAB EXAM WILL GET A ZERO GRADE.

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Grading distribution of the Laboratory Lab grade represents 25% of the total course grade.

Lab Exam I 10 %

Lab Exam II 10 %

Lab Review/pre Sessions/Quizzes (5 sessions) Quiz 1 (1%) Quiz 2 (0.5%) Lab2 Report (0.5%) Quiz 3 (0.5%) Lab3 Report (0.5%) Quiz 4 (1%) Quiz 5 (1%) Total 5 %

In addition to the five lab sessions, you are all required to attend and participate in the five Lab Review/Prep sessions. These sessions are worth 5% of the total course grade. These sessions are designed to help you prepare for your next week lab and to review the results/findings of the lab that you finished the week before. You will have quizzes. You are also required to submit with your partner two lab reports based on data obtained from Labs 2 & 3. So, come fully prepared to do your experimental work, record your data and finish the 3 hr lab session in a timely manner. Problems Any health-related problems that may arise from unexpected accidents (chemical spills, minor cuts ...) during lab time, please inform your TA, the lab supervisor and/or the lab supervisor specialist.

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Microscope Use 4

4.1 The Compound Microscope

Figure 1: Major features of a compound microscope: occular lens, 2-3 objective lenses, coarse and fine adjusatment knobs, and iris diaphragm.

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Using a compound microscope 1. Place the prepared slide on the microscope stage so that mounted specimen is centered over the hole in the stage. Use the stage clips to secure the slide in place. 2. Always begin with the lowest power objective. Rotate the nosepiece to bring the shortest objective (usually 4x) into position. 3. Turn the coarse adjustment knob to move the objective downward toward the slide until the point of the objective lens is just above (but not touching) the slide. 4. Turn on the microscope light and look into the eyepiece, holding your eye about 1/2 inch from the eyepiece. While looking into the eyepiece, use the coarse adjustment knob to raise the body tube slowly until the specimen comes into focus. Sharpen the image with the fine adjustment knob. If you see nothing, you may need to recenter the specimen over the hole in the statge. 5. Note that the contrast between light and dark can be adjusted using the substage, iris diaphragm. If the light is too bright, the image may be“washed out” (invisible). 6. While watching through the ocular lens, move the slide to the left or right. Which direction did the image of the specimen move? Now move the slide away from you or towards you. What direction did the image move now? 7. For greater magnification, rotate the nosepiece to bring a higher power (longer) objective into position. Whenever a higher power objective is in place, use only the fine focus adjustment to refocus! 8. Turn off the sub-stage light whenever you are not looking through the microscope! The bulbs are expensive and burn out quickly. 9. When you have finished using the compound microscope:

a. Turn off the light source. b. Rotate the nosepiece to the low power objective. c. Unplug the microscope and coil the wire loosely over the body tube. d. Cover the microscope.

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4.2 The Dissecting Microscope

The dissecting microscope differs from the compound scope in many ways: a. Total magnification is much lower (maximum either 30 or 45 power). b. Objective lens is equipped with a "zoom" adjustment. c. Two ocular lenses give a stereoscopic (3-D) view of the specimen. d. Only one focus adjustment knob. e. Longer "working distance" (between specimen and objective lens). Figure 2. Major features of the dissecting scope: stage (for specimen), ocular lenses, objective (zoom) lens, coarse focusing adjustment, light sources (both above and below specimen).

 Goggle images

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Using a dissecting microscope 1. Choose the proper illumination (lighting). Some specimens are better viewed using reflected light (with the light source above the specimen), others with transmitted light (with the light source under the specimen). 2. The total magnification of the microscope can be calculated by multiplying the power of the ocular lens (engraved on the side of the eye piece) by the power of the objective (zoom) lens (read from the dial on the zoom control knob). 3. The orientation of the image is intuitive – when you move the specimen, the image moves in the same direction – unlike the compound microscope.

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Lab Report Format 5

You will write two lab reports based on data from labs 2 & 3. A scientific report usually consists of the following:

1. Title 2. Introduction 3. Materials and Methods 4. Results 5. Discussion & Conclusion

Title The title should be less than ten words, is straightforward and reflects the factual content of the experiment. Introduction The introduction defines the subject of the report. It must outlines the scientific objective(s) for the experiments performed and give the reader sufficient background to understand the rest of the report. A good introduction will answer several questions, including the following:

 Why was this study performed?

 What is the specific purpose of the study? The specific hypotheses and experimental design pertinent to investigating the topic should be described. Materials and Methods Materials and methods used in the experiments should be reported in this section. Provide enough detail for the reader to understand the experiment without overwhelming him or her. Generally, this section attempts to answer the following questions:

 What materials were used? How were they used?

Results The results section should summarize the data from the experiments without discussing their implications. The data should be organized into tables, figures, graphs, photographs, and so on. All figures and tables should have descriptive titles. Figures and tables should be self- explanatory; that is, the reader should be able to understand them without referring to the text. All columns and rows in tables and axes in figures should be labeled. Discussion & Conclusion This section should not just be a restatement of the results but should emphasize interpretation of the data, relating them to existing theory and knowledge. Suggestions for the improvement of techniques or experimental design may also be included here. In writing this section, you should explain the logic that allows you to accept or reject your original hypotheses. Provide a conclusion based on the results that you got. By Warren D. Dolphin, Iowa State University (Modified by Dr. Bekdash)

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Lab 1 – Viewing and Measuring Cells 6

All living things on earth are basically similar: all are composed of one or more cells. The chemical reactions that support life occur inside cells. Cells don't arise spontaneously; they arise only from other cells. Each cell contains all the organism's hereditary information. This information is passed from parent to offspring through cells. How large is a cell? Are all cells about the same size? Why are cells so small? What limits cell size? You’ll soon know answers to all these questions! Cells are usually way too small to be seen with the naked eye. The human body is made up of trillions of cells. One of the largest human cells, the human ovum (egg cell) is only about the size of the period at the end of this sentence. Since most cells are much smaller than that, most of what we know about cells has been gained with the aid of microscopes. Lab learning objectives You will have mastered the content of this minicourse when you are able to: 1. Given a compound light microscope, locate, name and describe the functions of the light source,