Microscope Lab - PBworkskroymbhs.pbworks.com/w/file/fetch/45217742/Lab 2 Cell... · Web viewLab 2 Cell Microscope Lab PreAP Biology Making Wet-mount Slides of Plant and Animal Cells

Name______________________________Date______________ Period_______

Lab 2 Cell Microscope Lab PreAP Biology

Making Wet-mount Slides of Plant and Animal Cells Lab

PreLab Instructions:1. Read through the entire lab (next few pages), highlight and annotate.2. Fill out the cover page (p. 5 of packet) of your Formal Lab Report for this lab.

(Name on line in middle of first page; at bottom, put group members’ names, date, class period, and teacher’s name).

3. Write a title for your lab on the line at the top of page 6.4. Also on page 6, write (in your own words) an appropriate and thorough

background and introduction paragraph to this lab regarding the following information: The technology that had to be invented before cells could be discovered

and studied (section 1 of chapter 3) Cell theory (p. 55) The 4 features common to all cells (p. 56)

5. Write the purpose of the lab (1 sentence statement indicating the reason we are doing this lab). Read the objectives for this lab and write a statement of purpose in your lab notebook. Start your purpose with the words “The purpose of this lab is to…”

6. List 4 specific safety rules that pertain to this lab. You must include commentary on the use of the two chemicals required to stain your slides. You can find MSDS on them at http://www.flinnsci.com/search_MSDS.asp

7. Summarize your procedure in your own words in PARAGRAPH form. DO NOT give me a numbered list.

40x

Objectives Prepare a wet mount properly. Observe plant and animal cells

Compare structures of plant cell and animal cell.

Make proper scientific drawings.Materials

MicroscopeMicroscope slideCover slip

Medicine dropperToothpicksOnion

IodineMethylene Blue

Rules for Microscope Use1. Always carry the microscope in front of your body with two hands: one holding

the arm and the other supporting the base.2. Always start out with the lowest power objective (4x, red), center and focus

your object, then move up to the traditional low power objective (10x, yellow). Focus again before moving up to high power (40x, blue) objective lens.

3. Always use the fine adjustment knob under high power and never the coarse adjustment knob which is to be used only on low power.

4. Always store the microscope on low power with the stage as far down as possible.

5. Always return the slides to their proper location for storage and never put the microscope away with a slide on the stage.

6. Always turn the microscope off before unplugging.7. Use only lens paper to clean the lenses.8. Never drag the microscope across the desk. Place away from the edge of

table/counter.Rules for Scientific Drawings

1. Use white unlined paper and use a pencil to draw & shade and colored pencils to color (if required).

2. If you are drawing a specimen from a microscope, draw a circle to represent the field of view and make your drawing to scale.

3. The name of the specimen should be centered and underlined at the top of the drawing.

4. Lines for labels extend from the diagram to the right and should be parallel and end at the same point on the page.

5. Labels are printed beside the line, not above it.6. The magnification (if applicable) should be centered below the drawing. To

determine magnification:1.Multiply the power of the eyepiece (ocular) lens by the power of the

objective lens. The power of each is written on each lens.2.Eyepiece= 10x; Super Low Power (red)= 4x; Low Power (yellow)= 10x;

High Power (blue)= 40x.7. BE AS NEAT AS POSSIBLE.

Example of a correct scientific drawing: Example of an incorrect scientific drawing:Anacharis

2

10x

40x

10x Use 4x to focus, then move to 10x for low power

Use 4x to focus, then 10x , then up to 40x for high power

NEVER use coarse adjustment on high power

3

Procedure: Observing Plant and Animal Cells

Procedure 1: Human Epithelial (Cheek) Cells (animal cell)

1. Gently scrape the inside of your cheek with the end of a flat toothpick. You will not be able to see anything. Then, prepare a wet mount as discussed below.

2. Add one drop of Methylene blue to the slide.

3. Smear the toothpick in the drop and immediately add a coverslip.

4. Throw the toothpick away. Please do not place the toothpick on the lab table.

5. Observe under the lowest power to focus, then under low (100x) and high power (400x).

6. Draw what you see (in your formal lab report packet) on LOW (100x) and HIGH (400x) power. Follow ALL rules to make a proper scientific drawing.

7. Label the cell membrane, cytoplasm, and nucleus in both drawings. Don’t forget to put the title above and total magnification (#) below.

8. Wash and dry your slide and coverslip.

Procedure 2: Onion Cells (plant cell)

1. Prepare a wet mount as indicated below.a. Obtain a piece of onion skin from your teacher. b. Make sure it is perfectly flat without folds. c. Add one drop of iodine to the slide and put on coverslip.

2. After focusing on the lowest power (40x), observe and draw the cells (in your formal lab report packet) under LOW (100x) and HIGH (400x) power. Include your title and magnification on each drawing and follow the rest of the scientific drawing rules.

3. Label the cell wall, nucleus and cytoplasm on each drawing.

4. Wash and dry your slide and coverslip and clean up your lab area. Raise your hand when you believe your lab station is clean enough for your teacher to inspect.

4

5

Making Wet-mount Slides of Plant & Animal CellsFormal Lab Report 1

_____________________________________Name

Teacher____________________________

Period__________

Date________________________

6

Lab Partners _______________________________________________________

Title________________________________________________________________________________

(see prelab instructions for what to include on this page of your lab report)

Background/Introduction:Write (in your own words) an appropriate and thorough background and introduction paragraph to this lab regarding the following information: The technology that had to be invented before cells could be discovered and studied

(section 1 of chapter 3) Cell theory (p. 55) The 4 features common to all cells (p. 56)________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Purpose:Write the purpose of the lab (1 sentence statement indicating the reason we are doing this lab). Read the objectives for this lab and write a statement of purpose in your lab notebook. Start your purpose with the words “The purpose of this lab is to…”

________________________________________________________________________________________________________________________________________________________________________________________________________

Materials:MicroscopeMicroscope slideCover slipMedicine dropper

ToothpicksOnion (or prepared slide of plant cells)Lugol’s iodineMethylene blu

Safety: ____________________________________________________________________________________________ ____________________________________________________________________________________________ ____________________________________________________________________________________________ ____________________________________________________________________________________________

7

Procedure:________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Data:

Analysis & Conclusions (create 2 paragraphs per question, one to compare and the second to contrast)

8

1. Compare and contrast the cheek cells you viewed in this lab with the onion cells you viewed in this lab. Include general appearance, as well as the structures visible.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

2. Compare and contrast the cheek cells you viewed in this lab with the diagram of a typical animal cell shown in Figure 1 on the next page. ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

3. Compare and contrast the onion cells you viewed in this lab with the diagram of the typical plant cell shown in Figure 2 on the next page.____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

4. Compare and contrast typical animal cells and typical plant cells, such as those shown in the diagrams on the next page.____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

5. Discuss how the data in this lab is different from your expectations of what a cell looks like based on the diagrams and models you have seen.

9

Figure 1

Figure 2

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

10

11

Making Wet-mount Slides of Plant & Animal CellsFormal Lab Report - GRADING RUBRIC

PRELAB:Cover Page/Title ________/3 ptsBackground/Introduction:

Technology ________/4 pts Cell theory ________/4 pts 4 features common to all cells ________/4 pts

Purpose: Complete sentence incorporating the objectives of the lab ________/3 pts

Safety: 4 rules ________/2pts Specific precautions for chemicals

o Lugol’s iodine ________/1 ptso Methylene blue ________/1 pts

Procedure: Summary of both parts of the procedure ________/5 pts No numbering of steps!

LAB:Data:

Microscope Drawings Cheek Low Cheek High Onion Low Onion High

o Title above (1 pt each) _________ __________ ________ _______o Magnifications below (1 pt each) _________ __________ ________ _______o Neatly/accurately drawn(3 pts each) _________ __________ ________

_______o Pencil used, labels straight (1 pt each) _________ __________ ________

_______o Colored with colored pencil (1 pt each) _________ __________ ________

_______o 3 labels each (3 pts each) _________ __________ ________

_______

________/40 pts

POSTLAB:Analysis & Conclusions:

Question 1—Compare & Contrast Cheek & Onion slides________/7 pts

Question 2—Compare & Contrast Cheek slide & Animal diagram________/7 pts

Question 3—Compare & Contrast Onion slide & Plant diagram ________/7 pts Question 4—Compare & Contrast Animal & Plant diagrams ________/7 pts

Name ________________________Period ____

SCORE ____________

12

Question 5—How is lab different than you thought? ________/5 pts

Total pts missed _________________

13