LabThree: Microscopes and Cells

Unit 2 pg.29

Procedures: Complete in order; do not skip around or multi-task to try and save time

Complete 3.1

Complete 2.2

Complete 3.4

Your "Tour of the Cell" text chapter features many amazing electron microscope images (also called TEM for transmission electron microscope). Look up the following figures and briefly explain featured cell structure(s) AND what each does: Figures 6.8a, 6.11, 6.12, 6.13. 6.14, 6.15, 6.17, 6.18, and 6.24.

Complete 3.5A As

Complete only Trichonympha; note manual Fig. 3.6 and Color Plate 2 to assist you.

Complete 3.5B

For this exercise, you will be examining 2 different photosynthetic organisms: Anabaena and Spyrogyra. It will be your job to determine which is prokaryotic vs. eukaryotic, and which is unicellular, colonial, or multicellular. For each, you will need to prepare a "wet mount" (see below)

General Wet Mount Procedures Using Liquid Samples

Using a pipette, withdraw SMALL sample - make sure you can see green filaments

Place no more than 1 drop - with filaments - on slide and place a coverslip on the drop

If you used too much liquid, the coverslip will move/float – NOT GOOD

Complete 3.6C - Plant Cells

view/draw at 40X and answer new worksheet questions.

Complete 3.6C - Animal Cells

Each person will prepare his/her own cheek cell - AND complete scientific drawings of them

Follow procedures in your manual to prepare your stained cheek cell slide preparation.

Using the worksheet provided, hand-draw the entire field of view at 10X objective AND 40X. Good scientific drawings are simple, done in pencil, use stipples and lines (not shading or smudging), and accurately represent the relative size and abundance of things. When complete, label THREE cell structures you can see in your diagram.

WORKSHEET

Lab Three: Microscopes and Cells

Label the picture below using the following 2.1 terms: oculars, objectives, stage, coarse focus, fine focus, condenser, iris diaphragm, lamp, on/off, light intensity switch.

All the following are based on questions from exercise 2.2 pg 33 This exercise should be completed before looking at any real specimens (3.5 and beyond).

·  When you move the slide right, what direction does the image in the ocular move?

·  Is the image in the ocular inverted relative to the specimen on the stage?

·  Is the working distance greater with the 40X or the 10X?

·  What would be the total magnification if the ocular = 20X and the objective = 100X?

·  What is the diameter (mm) of the field of view using the 4X objective?

·  What is the relationship between the size of the field and magnification?

·  Both threads are in focus at the same time using the 10X or 40X objective?

·  Which objective that you examined today has the shortest depth of field?

Based on 2.5A-#2 pg 43 view Trichonympha using the 40X objective to answer the following questions.

Organelles
Present? / Prokaryote
or Eukaryote / Unicellular, Colonial, or Multicellular / Motility?
If yes, how?
Trichonympha

Complete the following for 2.5B-C pg. 44-46 View Anabaena, Spyrogyra, and Elodea at 40X and make simple pencil drawings that show the entire field of view with cells. Using this and other observations, complete the following table.

Anabaena / Spyrogyra / Elodea
Simple Drawing / / /
What Organelles
Do You See?
Prokaryote
or Eukaryote
Unicellular, Colonial, or Multicellular

(5) Using your textbook, explain the ballpark cell sizes for prokaryotes vs. eukaryotes.

2.5C: pg46 animal cells

Using the circles provided, hand-draw the entire field of view at 10X objective AND 40X. When complete, label THREE cell structures you can see in your diagram.

/ Title:
Total Magnification:
/ Title:
Total Magnification:

Complete the following table based on 2.4 #4 pg.41

The figures refer to your textbook.

Text Figure TEM / Featured Cell Structure(s) / Function
6.7a
6.10
6.11
6.12
6.13
6.14
6.17
6.18
6.24