SNC 2D/P: Biology
Name: __________________________
Preparing and Viewing Plant Cells Under a Microscope
1. Peel the delicate transparent tissue from the inner surface of a piece of onion using forceps
(tweezers).
2. Make a wet mount by placing the tissue, unwrinkled, in a small drop of water on a glass slide.
3. Add one small drop of Lugol's iodine stain to the tissue and cover with a cover slip as directed.
(* be careful - the Lugol's can stain and burn the skin!)
4. Examine the onion cells at low power, focus as necessary.
5. Next examine the cells at medium and high power.
6. Prepare a diagram of onion skin tissue showing three to four cells. Label the structures you can
identify from the microscope. (examples - cell membrane, nucleus, etc.) Follow the guidelines
for drawing and labelling a proper biological diagram.
Answer the following questions on a separate sheet of paper:
1. Describe the shape of the cells.
2. What cell structures and organelles can you see?
3. How come there are no chloroplasts evident?
4. Draw and label a diagram of an onion cell.
Biological Drawing Rubric
Biological
Drawing
Observations
Neatness
Level 4
Demonstrates all of
the requirements:
Uses stippling
Includes 2-3 cells
Title, magnification
Level 3
Demonstrates
most of the
requirements
Level 2
Demonstrates
some of the
requirements
Level 1
Demonstrates few
of the
requirements
Includes all
observations.
Labelled all visible
organelles correctly
Uses pencil
Uses ruler for labels
No eraser marks
Demonstrates
most of the
requirements
Demonstrates
some of the
requirements
Demonstrates few
of the
requirements
Demonstrates
most of the
requirements
Demonstrates
some of the
requirements
Demonstrates few
of the
requirements
Knowledge/
All Questions
Understanding answered correctly
Most Questions
Some Questions
Few Questions
answered correctly answered correctly answered correctly