My values of the sizes of Elodea
My values of the sizes of Human Cheek Cells
Data Processing
Sample Calculation
Measurements of Cells
Field of View
2100 μm
Magnification ratio = 40x = 10
4x
Field Diameter 2100 = 210 μm ± 50
10
Length of Elodea cells 3 fit
210 = 70 μm
3
% Difference
Experimental value-Predicted value x 100
Predicted Value
80.5- 77.7 x 100
77.7
= 3.6%
=4%
Mean
70+52.5+105+70+105
5
= 80.5
Conclusions and Evaluation
Conclusion
Plant cells and animal cells are very similar. They have four main differences that can be indentified by their shape, the cell wall, chloroplasts and vacuoles. Plants are usually in a rectangular shape surrounded by a cell wall that helps them stay in a rectangular shape. Animal cells are usually in a round oval shape and have no cell wall. Plants cells contain many chloroplasts that conduct photosynthesis while animal cells do not have those because animals do not make food through photosynthesis. Also Plant cells have a much bigger vacuole to contain water and waste while animal cells have a smaller one. Plant cells are also generally larger in size than animal cells.
Limitations of Experimental Design
In this experiment my experimental design did help answer my experimental question. Looking at the cells’ main structures worked well because those were displayed very clearly through the microscope including the cell walls, cell membrane, the nucleus and chloroplasts. However, examining the cell’s smaller structures and finding the elodea cells’ nucleus did not work very well because those were not visible through the microscope. Measuring the sizes of the cells worked fairly well because the cells’ outline were very clearly shown and it was simple to estimate how many cells would fit across the field of view. On the other hand, most of those measurements were only estimates and are not very precise. There were some outliers throughout the class’ values and my own values. Those were probably due the fact that the sizes of the cells were over or under estimated.
Suggestions for Improvements
Some improvements that could be made if I were to do this experiment again include spending more time to carefully estimate the sizes of the cells.
Analysis
- How does the arrangement of plant cells and animal cells differ?
Plant cells and animal cells are very similar. They have four main differences that can be indentified by their shape, the cell wall, chloroplasts and vacuoles. Plants are usually in a rectangular shape surrounded by a cell wall that helps them stay in a rectangular shape. Animal cells are usually in a round oval shape and have no cell wall. Plants cells contain many chloroplasts that conduct photosynthesis while animal cells do not have those because animals do not make food through photosynthesis. Also Plant cells have a much bigger vacuole to contain water and waste while animal cells have a smaller one. Plant cells are also generally larger in size than animal cells.
- Create a table that compares your estimates of the sizes of each tissue cell you studied. Which cells were larger animal or plant?
This table shows that plant cells are larger than animal cells
- Compare the Elodea cells to the tomato cells. Explain why the cells of the tomato do not appear to have any chloroplasts
Elodea cells are similar to tomato cells however, Elodea cells are rectangular in shape and tomato cells are circular. Tomato cells do not appear to have any chloroplasts because it is a fruit plant and therefore does not carry on photosynthesis like the Elodea cell. However, tomatoes have chromoplasts that give them the colour red.
- What structure did methylene blue stain in the animal tissue
The Methylene blue stain stained the cell membrane, the nucleus and some unidentifiable structures within the cells.
- What careers would make use of the techniques learned in this activity
Many careers would make use of the techniques demonstrated in this activity especially careers involved with science particularly the biology field. For example, careers involved in, medical forensics, medicine, pharmaceutical, dentistry and especially research.
WORKS CITED
Bobet, Ritter + al. Nelson Biology 11. Nelson Thomson Learning, 2002. 21-22.
